Auto merge of #101249 - matthiaskrgr:rollup-wahnoz8, r=matthiaskrgr

Rollup of 10 pull requests

Successful merges:

 - #100787 (Pretty printing give proper error message without panic)
 - #100838 (Suggest moving redundant generic args of an assoc fn to its trait)
 - #100844 (migrate rustc_query_system to use SessionDiagnostic)
 - #101140 (Update Clippy)
 - #101161 (Fix uintended diagnostic caused by `drain(..)`)
 - #101165 (Use more `into_iter` rather than `drain(..)`)
 - #101229 (Link “? operator” to relevant chapter in The Book)
 - #101230 (lint: avoid linting diag functions with diag lints)
 - #101236 (Avoid needless buffer zeroing in `std::sys::windows::fs`)
 - #101240 (Fix a typo on `wasm64-unknown-unknown` doc)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Cargo.lock

@@ -727,6 +727,7 @@ version = "0.1.65"
 dependencies = [
  "arrayvec",
  "if_chain",
+ "itertools",
  "rustc-semver",
 ]
 

compiler/rustc_ast/src/tokenstream.rs

@@ -555,7 +555,7 @@ impl TokenStreamBuilder {
 
                 // Get the first stream, which will become the result stream.
                 // If it's `None`, create an empty stream.
-                let mut iter = streams.drain(..);
+                let mut iter = streams.into_iter();
                 let mut res_stream_lrc = iter.next().unwrap().0;
 
                 // Append the subsequent elements to the result stream, after

compiler/rustc_data_structures/src/sorted_map.rs

@@ -164,7 +164,7 @@ impl<K: Ord, V> SortedMap<K, V> {
     /// It is up to the caller to make sure that the elements are sorted by key
     /// and that there are no duplicates.
     #[inline]
-    pub fn insert_presorted(&mut self, mut elements: Vec<(K, V)>) {
+    pub fn insert_presorted(&mut self, elements: Vec<(K, V)>) {
         if elements.is_empty() {
             return;
         }
@@ -173,28 +173,28 @@ impl<K: Ord, V> SortedMap<K, V> {
 
         let start_index = self.lookup_index_for(&elements[0].0);
 
-        let drain = match start_index {
+        let elements = match start_index {
             Ok(index) => {
-                let mut drain = elements.drain(..);
+                let mut elements = elements.into_iter();
-                self.data[index] = drain.next().unwrap();
+                self.data[index] = elements.next().unwrap();
-                drain
+                elements
             }
             Err(index) => {
                 if index == self.data.len() || elements.last().unwrap().0 < self.data[index].0 {
                     // We can copy the whole range without having to mix with
                     // existing elements.
-                    self.data.splice(index..index, elements.drain(..));
+                    self.data.splice(index..index, elements.into_iter());
                     return;
                 }
 
-                let mut drain = elements.drain(..);
+                let mut elements = elements.into_iter();
-                self.data.insert(index, drain.next().unwrap());
+                self.data.insert(index, elements.next().unwrap());
-                drain
+                elements
             }
         };
 
         // Insert the rest
-        for (k, v) in drain {
+        for (k, v) in elements {
             self.insert(k, v);
         }
     }

compiler/rustc_driver/src/pretty.rs

@@ -1,5 +1,6 @@
 //! The various pretty-printing routines.
 
+use crate::session_diagnostics::UnprettyDumpFail;
 use rustc_ast as ast;
 use rustc_ast_pretty::pprust;
 use rustc_errors::ErrorGuaranteed;
@@ -357,12 +358,15 @@ fn get_source(input: &Input, sess: &Session) -> (String, FileName) {
     (src, src_name)
 }
 
-fn write_or_print(out: &str, ofile: Option<&Path>) {
+fn write_or_print(out: &str, ofile: Option<&Path>, sess: &Session) {
     match ofile {
         None => print!("{}", out),
         Some(p) => {
             if let Err(e) = std::fs::write(p, out) {
-                panic!("print-print failed to write {} due to {}", p.display(), e);
+                sess.emit_fatal(UnprettyDumpFail {
+                    path: p.display().to_string(),
+                    err: e.to_string(),
+                });
             }
         }
     }
@@ -402,7 +406,7 @@ pub fn print_after_parsing(
         _ => unreachable!(),
     };
 
-    write_or_print(&out, ofile);
+    write_or_print(&out, ofile, sess);
 }
 
 pub fn print_after_hir_lowering<'tcx>(
@@ -468,7 +472,7 @@ pub fn print_after_hir_lowering<'tcx>(
         _ => unreachable!(),
     };
 
-    write_or_print(&out, ofile);
+    write_or_print(&out, ofile, tcx.sess);
 }
 
 // In an ideal world, this would be a public function called by the driver after
@@ -512,7 +516,7 @@ fn print_with_analysis(
         _ => unreachable!(),
     };
 
-    write_or_print(&out, ofile);
+    write_or_print(&out, ofile, tcx.sess);
 
     Ok(())
 }

compiler/rustc_driver/src/session_diagnostics.rs

@@ -31,3 +31,10 @@ pub(crate) struct RLinkRustcVersionMismatch<'a> {
 #[derive(SessionDiagnostic)]
 #[diag(driver::rlink_no_a_file)]
 pub(crate) struct RlinkNotAFile;
+
+#[derive(SessionDiagnostic)]
+#[diag(driver::unpretty_dump_fail)]
+pub(crate) struct UnprettyDumpFail {
+    pub path: String,
+    pub err: String,
+}

compiler/rustc_error_messages/locales/en-US/driver.ftl

@@ -9,3 +9,5 @@ driver_rlink_encoding_version_mismatch = .rlink file was produced with encoding
 driver_rlink_rustc_version_mismatch = .rlink file was produced by rustc version `{$rustc_version}`, but the current version is `{$current_version}`
 
 driver_rlink_no_a_file = rlink must be a file
+
+driver_unpretty_dump_fail = pretty-print failed to write `{$path}` due to error `{$err}`

compiler/rustc_error_messages/locales/en-US/query_system.ftl

@@ -0,0 +1,25 @@
+query_system_reentrant = internal compiler error: re-entrant incremental verify failure, suppressing message
+
+query_system_increment_compilation = internal compiler error: encountered incremental compilation error with {$dep_node}
+    .help = This is a known issue with the compiler. Run {$run_cmd} to allow your project to compile
+
+query_system_increment_compilation_note1 = Please follow the instructions below to create a bug report with the provided information
+query_system_increment_compilation_note2 = See <https://github.com/rust-lang/rust/issues/84970> for more information
+
+query_system_cycle = cycle detected when {$stack_bottom}
+
+query_system_cycle_usage = cycle used when {$usage}
+
+query_system_cycle_stack_single = ...which immediately requires {$stack_bottom} again
+
+query_system_cycle_stack_multiple = ...which again requires {$stack_bottom}, completing the cycle
+
+query_system_cycle_recursive_ty_alias = type aliases cannot be recursive
+query_system_cycle_recursive_ty_alias_help1 = consider using a struct, enum, or union instead to break the cycle
+query_system_cycle_recursive_ty_alias_help2 = see <https://doc.rust-lang.org/reference/types.html#recursive-types> for more information
+
+query_system_cycle_recursive_trait_alias = trait aliases cannot be recursive
+
+query_system_cycle_which_requires = ...which requires {$desc}...
+
+query_system_query_overflow = queries overflow the depth limit!

compiler/rustc_error_messages/src/lib.rs

@@ -50,6 +50,7 @@ fluent_messages! {
     passes => "../locales/en-US/passes.ftl",
     plugin_impl => "../locales/en-US/plugin_impl.ftl",
     privacy => "../locales/en-US/privacy.ftl",
+    query_system => "../locales/en-US/query_system.ftl",
     save_analysis => "../locales/en-US/save_analysis.ftl",
     ty_utils => "../locales/en-US/ty_utils.ftl",
     typeck => "../locales/en-US/typeck.ftl",

compiler/rustc_errors/src/diagnostic.rs

@@ -974,12 +974,12 @@ impl Diagnostic {
     fn sub_with_highlights<M: Into<SubdiagnosticMessage>>(
         &mut self,
         level: Level,
-        mut message: Vec<(M, Style)>,
+        message: Vec<(M, Style)>,
         span: MultiSpan,
         render_span: Option<MultiSpan>,
     ) {
         let message = message
-            .drain(..)
+            .into_iter()
             .map(|m| (self.subdiagnostic_message_to_diagnostic_message(m.0), m.1))
             .collect();
         let sub = SubDiagnostic { level, message, span, render_span };

compiler/rustc_errors/src/translation.rs

@@ -21,7 +21,7 @@ pub trait Translate {
     /// Typically performed once for each diagnostic at the start of `emit_diagnostic` and then
     /// passed around as a reference thereafter.
     fn to_fluent_args<'arg>(&self, args: &[DiagnosticArg<'arg>]) -> FluentArgs<'arg> {
-        FromIterator::from_iter(args.to_vec().drain(..))
+        FromIterator::from_iter(args.iter().cloned())
     }
 
     /// Convert `DiagnosticMessage`s to a string, performing translation if necessary.

compiler/rustc_lint/src/internal.rs

@@ -393,8 +393,14 @@ impl LateLintPass<'_> for Diagnostics {
             return;
         }
 
+        let mut found_parent_with_attr = false;
         let mut found_impl = false;
-        for (_, parent) in cx.tcx.hir().parent_iter(expr.hir_id) {
+        for (hir_id, parent) in cx.tcx.hir().parent_iter(expr.hir_id) {
+            if let Some(owner_did) = hir_id.as_owner() {
+                found_parent_with_attr = found_parent_with_attr
+                    || cx.tcx.has_attr(owner_did.to_def_id(), sym::rustc_lint_diagnostics);
+            }
+
             debug!(?parent);
             if let Node::Item(Item { kind: ItemKind::Impl(impl_), .. }) = parent &&
                 let Impl { of_trait: Some(of_trait), .. } = impl_ &&
@@ -407,7 +413,7 @@ impl LateLintPass<'_> for Diagnostics {
             }
         }
         debug!(?found_impl);
-        if !found_impl {
+        if !found_parent_with_attr && !found_impl {
             cx.struct_span_lint(DIAGNOSTIC_OUTSIDE_OF_IMPL, span, |lint| {
                 lint.build(fluent::lint::diag_out_of_impl).emit();
             })
@@ -425,7 +431,7 @@ impl LateLintPass<'_> for Diagnostics {
             }
         }
         debug!(?found_diagnostic_message);
-        if !found_diagnostic_message {
+        if !found_parent_with_attr && !found_diagnostic_message {
             cx.struct_span_lint(UNTRANSLATABLE_DIAGNOSTIC, span, |lint| {
                 lint.build(fluent::lint::untranslatable_diag).emit();
             })

compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs

@@ -239,7 +239,7 @@ impl DiagnosticDeriveBuilder {
             }
         }
 
-        Ok(tokens.drain(..).collect())
+        Ok(tokens.into_iter().collect())
     }
 
     fn generate_field_attrs_code(&mut self, binding_info: &BindingInfo<'_>) -> TokenStream {

compiler/rustc_macros/src/diagnostics/subdiagnostic.rs

@@ -12,7 +12,7 @@ use quote::{format_ident, quote};
 use std::collections::HashMap;
 use std::fmt;
 use std::str::FromStr;
-use syn::{spanned::Spanned, Attribute, Meta, MetaList, MetaNameValue, NestedMeta, Path};
+use syn::{spanned::Spanned, Meta, MetaList, MetaNameValue, NestedMeta, Path};
 use synstructure::{BindingInfo, Structure, VariantInfo};
 
 /// Which kind of suggestion is being created?
@@ -28,41 +28,8 @@ enum SubdiagnosticSuggestionKind {
     Verbose,
 }
 
-impl FromStr for SubdiagnosticSuggestionKind {
-    type Err = ();
-
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
-        match s {
-            "" => Ok(SubdiagnosticSuggestionKind::Normal),
-            "_short" => Ok(SubdiagnosticSuggestionKind::Short),
-            "_hidden" => Ok(SubdiagnosticSuggestionKind::Hidden),
-            "_verbose" => Ok(SubdiagnosticSuggestionKind::Verbose),
-            _ => Err(()),
-        }
-    }
-}
-
-impl SubdiagnosticSuggestionKind {
-    pub fn to_suggestion_style(&self) -> TokenStream {
-        match self {
-            SubdiagnosticSuggestionKind::Normal => {
-                quote! { rustc_errors::SuggestionStyle::ShowCode }
-            }
-            SubdiagnosticSuggestionKind::Short => {
-                quote! { rustc_errors::SuggestionStyle::HideCodeInline }
-            }
-            SubdiagnosticSuggestionKind::Hidden => {
-                quote! { rustc_errors::SuggestionStyle::HideCodeAlways }
-            }
-            SubdiagnosticSuggestionKind::Verbose => {
-                quote! { rustc_errors::SuggestionStyle::ShowAlways }
-            }
-        }
-    }
-}
-
 /// Which kind of subdiagnostic is being created from a variant?
-#[derive(Clone)]
+#[derive(Clone, Copy)]
 enum SubdiagnosticKind {
     /// `#[label(...)]`
     Label,
@@ -73,9 +40,31 @@ enum SubdiagnosticKind {
     /// `#[warning(...)]`
     Warn,
     /// `#[suggestion{,_short,_hidden,_verbose}]`
-    Suggestion { suggestion_kind: SubdiagnosticSuggestionKind, code: TokenStream },
+    Suggestion(SubdiagnosticSuggestionKind),
-    /// `#[multipart_suggestion{,_short,_hidden,_verbose}]`
+}
-    MultipartSuggestion { suggestion_kind: SubdiagnosticSuggestionKind },
+
+impl FromStr for SubdiagnosticKind {
+    type Err = ();
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "label" => Ok(SubdiagnosticKind::Label),
+            "note" => Ok(SubdiagnosticKind::Note),
+            "help" => Ok(SubdiagnosticKind::Help),
+            "warning" => Ok(SubdiagnosticKind::Warn),
+            "suggestion" => Ok(SubdiagnosticKind::Suggestion(SubdiagnosticSuggestionKind::Normal)),
+            "suggestion_short" => {
+                Ok(SubdiagnosticKind::Suggestion(SubdiagnosticSuggestionKind::Short))
+            }
+            "suggestion_hidden" => {
+                Ok(SubdiagnosticKind::Suggestion(SubdiagnosticSuggestionKind::Hidden))
+            }
+            "suggestion_verbose" => {
+                Ok(SubdiagnosticKind::Suggestion(SubdiagnosticSuggestionKind::Verbose))
+            }
+            _ => Err(()),
+        }
+    }
 }
 
 impl quote::IdentFragment for SubdiagnosticKind {
@@ -85,9 +74,17 @@ impl quote::IdentFragment for SubdiagnosticKind {
             SubdiagnosticKind::Note => write!(f, "note"),
             SubdiagnosticKind::Help => write!(f, "help"),
             SubdiagnosticKind::Warn => write!(f, "warn"),
-            SubdiagnosticKind::Suggestion { .. } => write!(f, "suggestion_with_style"),
+            SubdiagnosticKind::Suggestion(SubdiagnosticSuggestionKind::Normal) => {
-            SubdiagnosticKind::MultipartSuggestion { .. } => {
+                write!(f, "suggestion")
-                write!(f, "multipart_suggestion_with_style")
+            }
+            SubdiagnosticKind::Suggestion(SubdiagnosticSuggestionKind::Short) => {
+                write!(f, "suggestion_short")
+            }
+            SubdiagnosticKind::Suggestion(SubdiagnosticSuggestionKind::Hidden) => {
+                write!(f, "suggestion_hidden")
+            }
+            SubdiagnosticKind::Suggestion(SubdiagnosticSuggestionKind::Verbose) => {
+                write!(f, "suggestion_verbose")
             }
         }
     }
@@ -151,9 +148,11 @@ impl<'a> SessionSubdiagnosticDerive<'a> {
                     variant,
                     span,
                     fields: fields_map,
+                    kinds: Vec::new(),
+                    slugs: Vec::new(),
+                    code: None,
                     span_field: None,
                     applicability: None,
-                    has_suggestion_parts: false,
                 };
                 builder.into_tokens().unwrap_or_else(|v| v.to_compile_error())
             });
@@ -194,15 +193,21 @@ struct SessionSubdiagnosticDeriveBuilder<'a> {
     /// derive builder.
     fields: HashMap<String, TokenStream>,
 
+    /// Subdiagnostic kind of the type/variant.
+    kinds: Vec<(SubdiagnosticKind, proc_macro::Span)>,
+
+    /// Slugs of the subdiagnostic - corresponds to the Fluent identifier for the message - from the
+    /// `#[kind(slug)]` attribute on the type or variant.
+    slugs: Vec<(Path, proc_macro::Span)>,
+    /// If a suggestion, the code to suggest as a replacement - from the `#[kind(code = "...")]`
+    /// attribute on the type or variant.
+    code: Option<(TokenStream, proc_macro::Span)>,
+
     /// Identifier for the binding to the `#[primary_span]` field.
     span_field: Option<(proc_macro2::Ident, proc_macro::Span)>,
     /// If a suggestion, the identifier for the binding to the `#[applicability]` field or a
     /// `rustc_errors::Applicability::*` variant directly.
     applicability: Option<(TokenStream, proc_macro::Span)>,
-
-    /// Set to true when a `#[suggestion_part]` field is encountered, used to generate an error
-    /// during finalization if still `false`.
-    has_suggestion_parts: bool,
 }
 
 impl<'a> HasFieldMap for SessionSubdiagnosticDeriveBuilder<'a> {
@@ -212,133 +217,124 @@ impl<'a> HasFieldMap for SessionSubdiagnosticDeriveBuilder<'a> {
 }
 
 impl<'a> SessionSubdiagnosticDeriveBuilder<'a> {
-    fn identify_kind(
+    fn identify_kind(&mut self) -> Result<(), DiagnosticDeriveError> {
-        &mut self,
+        for (i, attr) in self.variant.ast().attrs.iter().enumerate() {
-    ) -> Result<Option<(SubdiagnosticKind, Path)>, DiagnosticDeriveError> {
-        let mut kind_slug = None;
-
-        for attr in self.variant.ast().attrs {
             let span = attr.span().unwrap();
 
             let name = attr.path.segments.last().unwrap().ident.to_string();
             let name = name.as_str();
 
             let meta = attr.parse_meta()?;
-            let Meta::List(MetaList { ref nested, .. }) = meta else {
+            let kind = match meta {
-                throw_invalid_attr!(attr, &meta);
+                Meta::List(MetaList { ref nested, .. }) => {
-            };
+                    let mut nested_iter = nested.into_iter();
-
+                    if let Some(nested_attr) = nested_iter.next() {
-            let mut kind = match name {
+                        match nested_attr {
-                "label" => SubdiagnosticKind::Label,
+                            NestedMeta::Meta(Meta::Path(path)) => {
-                "note" => SubdiagnosticKind::Note,
+                                self.slugs.push((path.clone(), span));
-                "help" => SubdiagnosticKind::Help,
+                            }
-                "warning" => SubdiagnosticKind::Warn,
+                            NestedMeta::Meta(meta @ Meta::NameValue(_))
-                _ => {
+                                if matches!(
-                    if let Some(suggestion_kind) =
+                                    meta.path().segments.last().unwrap().ident.to_string().as_str(),
-                        name.strip_prefix("suggestion").and_then(|s| s.parse().ok())
+                                    "code" | "applicability"
-                    {
+                                ) =>
-                        SubdiagnosticKind::Suggestion { suggestion_kind, code: TokenStream::new() }
+                            {
-                    } else if let Some(suggestion_kind) =
+                                // don't error for valid follow-up attributes
-                        name.strip_prefix("multipart_suggestion").and_then(|s| s.parse().ok())
+                            }
-                    {
+                            nested_attr => {
-                        SubdiagnosticKind::MultipartSuggestion { suggestion_kind }
+                                throw_invalid_nested_attr!(attr, &nested_attr, |diag| {
-                    } else {
+                                    diag.help(
-                        throw_invalid_attr!(attr, &meta);
+                                        "first argument of the attribute should be the diagnostic \
+                                         slug",
+                                    )
+                                })
+                            }
+                        };
                     }
-                }
-            };
 
-            let mut slug = None;
+                    for nested_attr in nested_iter {
-            let mut code = None;
+                        let meta = match nested_attr {
+                            NestedMeta::Meta(ref meta) => meta,
+                            _ => throw_invalid_nested_attr!(attr, &nested_attr),
+                        };
 
-            let mut nested_iter = nested.into_iter();
+                        let span = meta.span().unwrap();
-            if let Some(nested_attr) = nested_iter.next() {
+                        let nested_name = meta.path().segments.last().unwrap().ident.to_string();
-                match nested_attr {
+                        let nested_name = nested_name.as_str();
-                    NestedMeta::Meta(Meta::Path(path)) => {
-                        slug.set_once((path.clone(), span));
-                    }
-                    NestedMeta::Meta(meta @ Meta::NameValue(_))
-                        if matches!(
-                            meta.path().segments.last().unwrap().ident.to_string().as_str(),
-                            "code" | "applicability"
-                        ) =>
-                    {
-                        // Don't error for valid follow-up attributes.
-                    }
-                    nested_attr => {
-                        throw_invalid_nested_attr!(attr, &nested_attr, |diag| {
-                            diag.help(
-                                "first argument of the attribute should be the diagnostic \
-                                 slug",
-                            )
-                        })
-                    }
-                };
-            }
 
-            for nested_attr in nested_iter {
+                        match meta {
-                let meta = match nested_attr {
+                            Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(s), .. }) => {
-                    NestedMeta::Meta(ref meta) => meta,
+                                match nested_name {
-                    _ => throw_invalid_nested_attr!(attr, &nested_attr),
+                                    "code" => {
-                };
+                                        let formatted_str = self.build_format(&s.value(), s.span());
-
+                                        self.code.set_once((formatted_str, span));
-                let span = meta.span().unwrap();
+                                    }
-                let nested_name = meta.path().segments.last().unwrap().ident.to_string();
+                                    "applicability" => {
-                let nested_name = nested_name.as_str();
+                                        let value = match Applicability::from_str(&s.value()) {
-
+                                            Ok(v) => v,
-                let value = match meta {
+                                            Err(()) => {
-                    Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(value), .. }) => value,
+                                                span_err(span, "invalid applicability").emit();
-                    Meta::Path(_) => throw_invalid_nested_attr!(attr, &nested_attr, |diag| {
+                                                Applicability::Unspecified
-                        diag.help("a diagnostic slug must be the first argument to the attribute")
+                                            }
-                    }),
+                                        };
-                    _ => throw_invalid_nested_attr!(attr, &nested_attr),
+                                        self.applicability.set_once((quote! { #value }, span));
-                };
+                                    }
-
+                                    _ => throw_invalid_nested_attr!(attr, &nested_attr, |diag| {
-                match nested_name {
+                                        diag.help(
-                    "code" => {
+                                            "only `code` and `applicability` are valid nested \
-                        if matches!(kind, SubdiagnosticKind::Suggestion { .. }) {
+                                             attributes",
-                            let formatted_str = self.build_format(&value.value(), value.span());
+                                        )
-                            code.set_once((formatted_str, span));
+                                    }),
-                        } else {
+                                }
-                            span_err(
+                            }
-                                span,
+                            _ => throw_invalid_nested_attr!(attr, &nested_attr, |diag| {
-                                &format!(
+                                if matches!(meta, Meta::Path(_)) {
-                                    "`code` is not a valid nested attribute of a `{}` attribute",
+                                    diag.help(
-                                    name
+                                        "a diagnostic slug must be the first argument to the \
-                                ),
+                                         attribute",
-                            )
+                                    )
-                            .emit();
+                                } else {
+                                    diag
+                                }
+                            }),
                         }
                     }
-                    "applicability" => {
+
-                        if matches!(
+                    let Ok(kind) = SubdiagnosticKind::from_str(name) else {
-                            kind,
+                        throw_invalid_attr!(attr, &meta)
-                            SubdiagnosticKind::Suggestion { .. }
+                    };
-                                | SubdiagnosticKind::MultipartSuggestion { .. }
+
-                        ) {
+                    kind
-                            let value =
-                                Applicability::from_str(&value.value()).unwrap_or_else(|()| {
-                                    span_err(span, "invalid applicability").emit();
-                                    Applicability::Unspecified
-                                });
-                            self.applicability.set_once((quote! { #value }, span));
-                        } else {
-                            span_err(
-                                span,
-                                &format!(
-                                    "`applicability` is not a valid nested attribute of a `{}` attribute",
-                                    name
-                                )
-                            ).emit();
-                        }
-                    }
-                    _ => throw_invalid_nested_attr!(attr, &nested_attr, |diag| {
-                        diag.help("only `code` and `applicability` are valid nested attributes")
-                    }),
                 }
+                _ => throw_invalid_attr!(attr, &meta),
+            };
+
+            if matches!(
+                kind,
+                SubdiagnosticKind::Label | SubdiagnosticKind::Help | SubdiagnosticKind::Note
+            ) && self.code.is_some()
+            {
+                throw_span_err!(
+                    span,
+                    &format!("`code` is not a valid nested attribute of a `{}` attribute", name)
+                );
             }
 
-            let Some((slug, _)) = slug else {
+            if matches!(
+                kind,
+                SubdiagnosticKind::Label | SubdiagnosticKind::Help | SubdiagnosticKind::Note
+            ) && self.applicability.is_some()
+            {
+                throw_span_err!(
+                    span,
+                    &format!(
+                        "`applicability` is not a valid nested attribute of a `{}` attribute",
+                        name
+                    )
+                );
+            }
+
+            if self.slugs.len() != i + 1 {
                 throw_span_err!(
                     span,
                     &format!(
@@ -346,338 +342,146 @@ impl<'a> SessionSubdiagnosticDeriveBuilder<'a> {
                         name
                     )
                 );
-            };
-
-            match kind {
-                SubdiagnosticKind::Suggestion { code: ref mut code_field, .. } => {
-                    let Some((code, _)) = code else {
-                        throw_span_err!(span, "suggestion without `code = \"...\"`");
-                    };
-                    *code_field = code;
-                }
-                SubdiagnosticKind::Label
-                | SubdiagnosticKind::Note
-                | SubdiagnosticKind::Help
-                | SubdiagnosticKind::Warn
-                | SubdiagnosticKind::MultipartSuggestion { .. } => {}
             }
 
-            kind_slug.set_once(((kind, slug), span))
+            self.kinds.push((kind, span));
         }
 
-        Ok(kind_slug.map(|(kind_slug, _)| kind_slug))
+        Ok(())
     }
 
-    /// Generates the code for a field with no attributes.
+    fn generate_field_code(
-    fn generate_field_set_arg(&mut self, binding: &BindingInfo<'_>) -> TokenStream {
+        &mut self,
+        binding: &BindingInfo<'_>,
+        have_suggestion: bool,
+    ) -> Result<TokenStream, DiagnosticDeriveError> {
         let ast = binding.ast();
-        assert_eq!(ast.attrs.len(), 0, "field with attribute used as diagnostic arg");
+
+        let inner_ty = FieldInnerTy::from_type(&ast.ty);
+        let info = FieldInfo {
+            binding: binding,
+            ty: inner_ty.inner_type().unwrap_or(&ast.ty),
+            span: &ast.span(),
+        };
+
+        for attr in &ast.attrs {
+            let name = attr.path.segments.last().unwrap().ident.to_string();
+            let name = name.as_str();
+            let span = attr.span().unwrap();
+
+            let meta = attr.parse_meta()?;
+            match meta {
+                Meta::Path(_) => match name {
+                    "primary_span" => {
+                        report_error_if_not_applied_to_span(attr, &info)?;
+                        self.span_field.set_once((binding.binding.clone(), span));
+                        return Ok(quote! {});
+                    }
+                    "applicability" if have_suggestion => {
+                        report_error_if_not_applied_to_applicability(attr, &info)?;
+                        let binding = binding.binding.clone();
+                        self.applicability.set_once((quote! { #binding }, span));
+                        return Ok(quote! {});
+                    }
+                    "applicability" => {
+                        span_err(span, "`#[applicability]` is only valid on suggestions").emit();
+                        return Ok(quote! {});
+                    }
+                    "skip_arg" => {
+                        return Ok(quote! {});
+                    }
+                    _ => throw_invalid_attr!(attr, &meta, |diag| {
+                        diag.help(
+                            "only `primary_span`, `applicability` and `skip_arg` are valid field \
+                             attributes",
+                        )
+                    }),
+                },
+                _ => throw_invalid_attr!(attr, &meta),
+            }
+        }
+
+        let ident = ast.ident.as_ref().unwrap();
 
         let diag = &self.diag;
-        let ident = ast.ident.as_ref().unwrap();
+        let generated = quote! {
-        quote! {
             #diag.set_arg(
                 stringify!(#ident),
                 #binding
             );
-        }
+        };
+
+        Ok(inner_ty.with(binding, generated))
     }
 
-    /// Generates the necessary code for all attributes on a field.
+    fn into_tokens(&mut self) -> Result<TokenStream, DiagnosticDeriveError> {
-    fn generate_field_attr_code(
+        self.identify_kind()?;
-        &mut self,
+        if self.kinds.is_empty() {
-        binding: &BindingInfo<'_>,
-        kind: &SubdiagnosticKind,
-    ) -> TokenStream {
-        let ast = binding.ast();
-        assert!(ast.attrs.len() > 0, "field without attributes generating attr code");
-
-        // Abstract over `Vec<T>` and `Option<T>` fields using `FieldInnerTy`, which will
-        // apply the generated code on each element in the `Vec` or `Option`.
-        let inner_ty = FieldInnerTy::from_type(&ast.ty);
-        ast.attrs
-            .iter()
-            .map(|attr| {
-                let info = FieldInfo {
-                    binding,
-                    ty: inner_ty.inner_type().unwrap_or(&ast.ty),
-                    span: &ast.span(),
-                };
-
-                let generated = self
-                    .generate_field_code_inner(kind, attr, info)
-                    .unwrap_or_else(|v| v.to_compile_error());
-
-                inner_ty.with(binding, generated)
-            })
-            .collect()
-    }
-
-    fn generate_field_code_inner(
-        &mut self,
-        kind: &SubdiagnosticKind,
-        attr: &Attribute,
-        info: FieldInfo<'_>,
-    ) -> Result<TokenStream, DiagnosticDeriveError> {
-        let meta = attr.parse_meta()?;
-        match meta {
-            Meta::Path(path) => self.generate_field_code_inner_path(kind, attr, info, path),
-            Meta::List(list @ MetaList { .. }) => {
-                self.generate_field_code_inner_list(kind, attr, info, list)
-            }
-            _ => throw_invalid_attr!(attr, &meta),
-        }
-    }
-
-    /// Generates the code for a `[Meta::Path]`-like attribute on a field (e.g. `#[primary_span]`).
-    fn generate_field_code_inner_path(
-        &mut self,
-        kind: &SubdiagnosticKind,
-        attr: &Attribute,
-        info: FieldInfo<'_>,
-        path: Path,
-    ) -> Result<TokenStream, DiagnosticDeriveError> {
-        let span = attr.span().unwrap();
-        let ident = &path.segments.last().unwrap().ident;
-        let name = ident.to_string();
-        let name = name.as_str();
-
-        match name {
-            "skip_arg" => Ok(quote! {}),
-            "primary_span" => {
-                if matches!(kind, SubdiagnosticKind::MultipartSuggestion { .. }) {
-                    throw_invalid_attr!(attr, &Meta::Path(path), |diag| {
-                        diag.help(
-                            "multipart suggestions use one or more `#[suggestion_part]`s rather \
-                            than one `#[primary_span]`",
-                        )
-                    })
-                }
-
-                report_error_if_not_applied_to_span(attr, &info)?;
-
-                let binding = info.binding.binding.clone();
-                self.span_field.set_once((binding, span));
-
-                Ok(quote! {})
-            }
-            "suggestion_part" => {
-                self.has_suggestion_parts = true;
-
-                match kind {
-                    SubdiagnosticKind::MultipartSuggestion { .. } => {
-                        span_err(
-                            span,
-                            "`#[suggestion_part(...)]` attribute without `code = \"...\"`",
-                        )
-                        .emit();
-                        Ok(quote! {})
-                    }
-                    SubdiagnosticKind::Label
-                    | SubdiagnosticKind::Note
-                    | SubdiagnosticKind::Help
-                    | SubdiagnosticKind::Warn
-                    | SubdiagnosticKind::Suggestion { .. } => {
-                        throw_invalid_attr!(attr, &Meta::Path(path), |diag| {
-                            diag.help(
-                                "`#[suggestion_part(...)]` is only valid in multipart suggestions, use `#[primary_span]` instead",
-                            )
-                        });
-                    }
-                }
-            }
-            "applicability" => {
-                if let SubdiagnosticKind::Suggestion { .. }
-                | SubdiagnosticKind::MultipartSuggestion { .. } = kind
-                {
-                    report_error_if_not_applied_to_applicability(attr, &info)?;
-
-                    let binding = info.binding.binding.clone();
-                    self.applicability.set_once((quote! { #binding }, span));
-                } else {
-                    span_err(span, "`#[applicability]` is only valid on suggestions").emit();
-                }
-
-                Ok(quote! {})
-            }
-            _ => throw_invalid_attr!(attr, &Meta::Path(path), |diag| {
-                let span_attr = if let SubdiagnosticKind::MultipartSuggestion { .. } = kind {
-                    "suggestion_part"
-                } else {
-                    "primary_span"
-                };
-                diag.help(format!(
-                    "only `{span_attr}`, `applicability` and `skip_arg` are valid field attributes",
-                ))
-            }),
-        }
-    }
-
-    /// Generates the code for a `[Meta::List]`-like attribute on a field (e.g.
-    /// `#[suggestion_part(code = "...")]`).
-    fn generate_field_code_inner_list(
-        &mut self,
-        kind: &SubdiagnosticKind,
-        attr: &Attribute,
-        info: FieldInfo<'_>,
-        list: MetaList,
-    ) -> Result<TokenStream, DiagnosticDeriveError> {
-        let span = attr.span().unwrap();
-        let ident = &list.path.segments.last().unwrap().ident;
-        let name = ident.to_string();
-        let name = name.as_str();
-
-        match name {
-            "suggestion_part" => {
-                if !matches!(kind, SubdiagnosticKind::MultipartSuggestion { .. }) {
-                    throw_invalid_attr!(attr, &Meta::List(list), |diag| {
-                        diag.help(
-                            "`#[suggestion_part(...)]` is only valid in multipart suggestions",
-                        )
-                    })
-                }
-
-                self.has_suggestion_parts = true;
-
-                report_error_if_not_applied_to_span(attr, &info)?;
-
-                let mut code = None;
-                for nested_attr in list.nested.iter() {
-                    let NestedMeta::Meta(ref meta) = nested_attr else {
-                        throw_invalid_nested_attr!(attr, &nested_attr);
-                    };
-
-                    let span = meta.span().unwrap();
-                    let nested_name = meta.path().segments.last().unwrap().ident.to_string();
-                    let nested_name = nested_name.as_str();
-
-                    let Meta::NameValue(MetaNameValue { lit: syn::Lit::Str(value), .. }) = meta else {
-                        throw_invalid_nested_attr!(attr, &nested_attr);
-                    };
-
-                    match nested_name {
-                        "code" => {
-                            let formatted_str = self.build_format(&value.value(), value.span());
-                            code.set_once((formatted_str, span));
-                        }
-                        _ => throw_invalid_nested_attr!(attr, &nested_attr, |diag| {
-                            diag.help("`code` is the only valid nested attribute")
-                        }),
-                    }
-                }
-
-                let Some((code, _)) = code else {
-                    span_err(span, "`#[suggestion_part(...)]` attribute without `code = \"...\"`")
-                        .emit();
-                    return Ok(quote! {});
-                };
-                let binding = info.binding;
-
-                Ok(quote! { suggestions.push((#binding, #code)); })
-            }
-            _ => throw_invalid_attr!(attr, &Meta::List(list), |diag| {
-                let span_attr = if let SubdiagnosticKind::MultipartSuggestion { .. } = kind {
-                    "suggestion_part"
-                } else {
-                    "primary_span"
-                };
-                diag.help(format!(
-                    "only `{span_attr}`, `applicability` and `skip_arg` are valid field attributes",
-                ))
-            }),
-        }
-    }
-
-    pub fn into_tokens(&mut self) -> Result<TokenStream, DiagnosticDeriveError> {
-        let Some((kind, slug)) = self.identify_kind()? else {
             throw_span_err!(
                 self.variant.ast().ident.span().unwrap(),
                 "subdiagnostic kind not specified"
             );
         };
+        let have_suggestion =
+            self.kinds.iter().any(|(k, _)| matches!(k, SubdiagnosticKind::Suggestion(_)));
+        let mut args = TokenStream::new();
+        for binding in self.variant.bindings() {
+            let arg = self
+                .generate_field_code(binding, have_suggestion)
+                .unwrap_or_else(|v| v.to_compile_error());
+            args.extend(arg);
+        }
+        let mut tokens = TokenStream::new();
+        for ((kind, _), (slug, _)) in self.kinds.iter().zip(&self.slugs) {
+            let code = match self.code.as_ref() {
+                Some((code, _)) => Some(quote! { #code }),
+                None if have_suggestion => {
+                    span_err(self.span, "suggestion without `code = \"...\"`").emit();
+                    Some(quote! { /* macro error */ "..." })
+                }
+                None => None,
+            };
 
-        let init = match &kind {
+            let span_field = self.span_field.as_ref().map(|(span, _)| span);
-            SubdiagnosticKind::Label
+            let applicability = match self.applicability.clone() {
-            | SubdiagnosticKind::Note
+                Some((applicability, _)) => Some(applicability),
-            | SubdiagnosticKind::Help
+                None if have_suggestion => {
-            | SubdiagnosticKind::Warn
+                    span_err(self.span, "suggestion without `applicability`").emit();
-            | SubdiagnosticKind::Suggestion { .. } => quote! {},
+                    Some(quote! { rustc_errors::Applicability::Unspecified })
-            SubdiagnosticKind::MultipartSuggestion { .. } => {
+                }
-                quote! { let mut suggestions = Vec::new(); }
+                None => None,
-            }
+            };
-        };
 
-        let attr_args: TokenStream = self
+            let diag = &self.diag;
-            .variant
+            let name = format_ident!("{}{}", if span_field.is_some() { "span_" } else { "" }, kind);
-            .bindings()
+            let message = quote! { rustc_errors::fluent::#slug };
-            .iter()
+            let call = if matches!(kind, SubdiagnosticKind::Suggestion(..)) {
-            .filter(|binding| !binding.ast().attrs.is_empty())
-            .map(|binding| self.generate_field_attr_code(binding, &kind))
-            .collect();
-
-        let span_field = self.span_field.as_ref().map(|(span, _)| span);
-        let applicability = self.applicability.take().map_or_else(
-            || quote! { rustc_errors::Applicability::Unspecified },
-            |(applicability, _)| applicability,
-        );
-
-        let diag = &self.diag;
-        let name = format_ident!("{}{}", if span_field.is_some() { "span_" } else { "" }, kind);
-        let message = quote! { rustc_errors::fluent::#slug };
-        let call = match kind {
-            SubdiagnosticKind::Suggestion { suggestion_kind, code } => {
                 if let Some(span) = span_field {
-                    let style = suggestion_kind.to_suggestion_style();
+                    quote! { #diag.#name(#span, #message, #code, #applicability); }
-
-                    quote! { #diag.#name(#span, #message, #code, #applicability, #style); }
                 } else {
                     span_err(self.span, "suggestion without `#[primary_span]` field").emit();
                     quote! { unreachable!(); }
                 }
-            }
+            } else if matches!(kind, SubdiagnosticKind::Label) {
-            SubdiagnosticKind::MultipartSuggestion { suggestion_kind } => {
-                if !self.has_suggestion_parts {
-                    span_err(
-                        self.span,
-                        "multipart suggestion without any `#[suggestion_part(...)]` fields",
-                    )
-                    .emit();
-                }
-
-                let style = suggestion_kind.to_suggestion_style();
-
-                quote! { #diag.#name(#message, suggestions, #applicability, #style); }
-            }
-            SubdiagnosticKind::Label => {
                 if let Some(span) = span_field {
                     quote! { #diag.#name(#span, #message); }
                 } else {
                     span_err(self.span, "label without `#[primary_span]` field").emit();
                     quote! { unreachable!(); }
                 }
-            }
+            } else {
-            _ => {
                 if let Some(span) = span_field {
                     quote! { #diag.#name(#span, #message); }
                 } else {
                     quote! { #diag.#name(#message); }
                 }
-            }
+            };
-        };
+            tokens.extend(quote! {
+                #call
+                #args
+            });
+        }
 
-        let plain_args: TokenStream = self
+        Ok(tokens)
-            .variant
-            .bindings()
-            .iter()
-            .filter(|binding| binding.ast().attrs.is_empty())
-            .map(|binding| self.generate_field_set_arg(binding))
-            .collect();
-
-        Ok(quote! {
-            #init
-            #attr_args
-            #call
-            #plain_args
-        })
     }
 }

compiler/rustc_query_system/src/error.rs

@@ -0,0 +1,73 @@
+use rustc_errors::AddSubdiagnostic;
+use rustc_span::Span;
+
+pub struct CycleStack {
+    pub span: Span,
+    pub desc: String,
+}
+
+impl AddSubdiagnostic for CycleStack {
+    fn add_to_diagnostic(self, diag: &mut rustc_errors::Diagnostic) {
+        diag.span_note(self.span, &format!("...which requires {}...", self.desc));
+    }
+}
+
+#[derive(SessionSubdiagnostic)]
+pub enum StackCount {
+    #[note(query_system::cycle_stack_single)]
+    Single,
+    #[note(query_system::cycle_stack_multiple)]
+    Multiple,
+}
+
+#[derive(SessionSubdiagnostic)]
+pub enum Alias {
+    #[note(query_system::cycle_recursive_ty_alias)]
+    #[help(query_system::cycle_recursive_ty_alias_help1)]
+    #[help(query_system::cycle_recursive_ty_alias_help2)]
+    Ty,
+    #[note(query_system::cycle_recursive_trait_alias)]
+    Trait,
+}
+
+#[derive(SessionSubdiagnostic)]
+#[note(query_system::cycle_usage)]
+pub struct CycleUsage {
+    #[primary_span]
+    pub span: Span,
+    pub usage: String,
+}
+
+#[derive(SessionDiagnostic)]
+#[diag(query_system::cycle, code = "E0391")]
+pub struct Cycle {
+    #[primary_span]
+    pub span: Span,
+    pub stack_bottom: String,
+    #[subdiagnostic]
+    pub cycle_stack: Vec<CycleStack>,
+    #[subdiagnostic]
+    pub stack_count: StackCount,
+    #[subdiagnostic]
+    pub alias: Option<Alias>,
+    #[subdiagnostic]
+    pub cycle_usage: Option<CycleUsage>,
+}
+
+#[derive(SessionDiagnostic)]
+#[diag(query_system::reentrant)]
+pub struct Reentrant;
+
+#[derive(SessionDiagnostic)]
+#[diag(query_system::increment_compilation)]
+#[help]
+#[note(query_system::increment_compilation_note1)]
+#[note(query_system::increment_compilation_note2)]
+pub struct IncrementCompilation {
+    pub run_cmd: String,
+    pub dep_node: String,
+}
+
+#[derive(SessionDiagnostic)]
+#[diag(query_system::query_overflow)]
+pub struct QueryOverflow;

compiler/rustc_query_system/src/lib.rs

@@ -5,6 +5,8 @@
 #![feature(min_specialization)]
 #![feature(extern_types)]
 #![allow(rustc::potential_query_instability)]
+// #![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 
 #[macro_use]
 extern crate tracing;
@@ -15,5 +17,6 @@ extern crate rustc_macros;
 
 pub mod cache;
 pub mod dep_graph;
+mod error;
 pub mod ich;
 pub mod query;

compiler/rustc_query_system/src/query/job.rs

@@ -1,12 +1,11 @@
+use crate::error::CycleStack;
 use crate::query::plumbing::CycleError;
 use crate::query::{QueryContext, QueryStackFrame};
-use rustc_hir::def::DefKind;
 
 use rustc_data_structures::fx::FxHashMap;
-use rustc_errors::{
+use rustc_errors::{Diagnostic, DiagnosticBuilder, ErrorGuaranteed, Handler, Level};
-    struct_span_err, Diagnostic, DiagnosticBuilder, ErrorGuaranteed, Handler, Level,
+use rustc_hir::def::DefKind;
-};
+use rustc_session::{Session, SessionDiagnostic};
-use rustc_session::Session;
 use rustc_span::Span;
 
 use std::hash::Hash;
@@ -536,46 +535,44 @@ pub(crate) fn report_cycle<'a>(
     assert!(!stack.is_empty());
 
     let span = stack[0].query.default_span(stack[1 % stack.len()].span);
-    let mut err =
+
-        struct_span_err!(sess, span, E0391, "cycle detected when {}", stack[0].query.description);
+    let mut cycle_stack = Vec::new();
+
+    use crate::error::StackCount;
+    let stack_count = if stack.len() == 1 { StackCount::Single } else { StackCount::Multiple };
 
     for i in 1..stack.len() {
         let query = &stack[i].query;
         let span = query.default_span(stack[(i + 1) % stack.len()].span);
-        err.span_note(span, &format!("...which requires {}...", query.description));
+        cycle_stack.push(CycleStack { span, desc: query.description.to_owned() });
-    }
-
-    if stack.len() == 1 {
-        err.note(&format!("...which immediately requires {} again", stack[0].query.description));
-    } else {
-        err.note(&format!(
-            "...which again requires {}, completing the cycle",
-            stack[0].query.description
-        ));
-    }
-
-    if stack.iter().all(|entry| {
-        entry
-            .query
-            .def_kind
-            .map_or(false, |def_kind| matches!(def_kind, DefKind::TyAlias | DefKind::TraitAlias))
-    }) {
-        if stack.iter().all(|entry| {
-            entry.query.def_kind.map_or(false, |def_kind| matches!(def_kind, DefKind::TyAlias))
-        }) {
-            err.note("type aliases cannot be recursive");
-            err.help("consider using a struct, enum, or union instead to break the cycle");
-            err.help("see <https://doc.rust-lang.org/reference/types.html#recursive-types> for more information");
-        } else {
-            err.note("trait aliases cannot be recursive");
-        }
     }
 
+    let mut cycle_usage = None;
     if let Some((span, query)) = usage {
-        err.span_note(query.default_span(span), &format!("cycle used when {}", query.description));
+        cycle_usage = Some(crate::error::CycleUsage {
+            span: query.default_span(span),
+            usage: query.description,
+        });
     }
 
-    err
+    let alias = if stack.iter().all(|entry| entry.query.def_kind == Some(DefKind::TyAlias)) {
+        Some(crate::error::Alias::Ty)
+    } else if stack.iter().all(|entry| entry.query.def_kind == Some(DefKind::TraitAlias)) {
+        Some(crate::error::Alias::Trait)
+    } else {
+        None
+    };
+
+    let cycle_diag = crate::error::Cycle {
+        span,
+        cycle_stack,
+        stack_bottom: stack[0].query.description.to_owned(),
+        alias,
+        cycle_usage: cycle_usage,
+        stack_count,
+    };
+
+    cycle_diag.into_diagnostic(&sess.parse_sess)
 }
 
 pub fn print_query_stack<CTX: QueryContext>(

compiler/rustc_query_system/src/query/mod.rs

@@ -125,6 +125,6 @@ pub trait QueryContext: HasDepContext {
     ) -> R;
 
     fn depth_limit_error(&self) {
-        self.dep_context().sess().fatal("queries overflow the depth limit!");
+        self.dep_context().sess().emit_fatal(crate::error::QueryOverflow);
     }
 }

compiler/rustc_query_system/src/query/plumbing.rs

@@ -618,16 +618,12 @@ fn incremental_verify_ich_cold(sess: &Session, dep_node: DebugArg<'_>, result: D
     let old_in_panic = INSIDE_VERIFY_PANIC.with(|in_panic| in_panic.replace(true));
 
     if old_in_panic {
-        sess.struct_err(
+        sess.emit_err(crate::error::Reentrant);
-            "internal compiler error: re-entrant incremental verify failure, suppressing message",
-        )
-        .emit();
     } else {
-        sess.struct_err(&format!("internal compiler error: encountered incremental compilation error with {:?}", dep_node))
+        sess.emit_err(crate::error::IncrementCompilation {
-                .help(&format!("This is a known issue with the compiler. Run {} to allow your project to compile", run_cmd))
+            run_cmd,
-                .note("Please follow the instructions below to create a bug report with the provided information")
+            dep_node: format!("{:?}", dep_node),
-                .note("See <https://github.com/rust-lang/rust/issues/84970> for more information")
+        });
-                .emit();
         panic!("Found unstable fingerprints for {:?}: {:?}", dep_node, result);
     }
 

compiler/rustc_resolve/src/late/diagnostics.rs

@@ -1792,7 +1792,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                 }
             };
 
-            let mut suggestable_variants = variants
+            let suggestable_variants = variants
                 .iter()
                 .filter(|(_, def_id, kind)| !needs_placeholder(*def_id, *kind))
                 .map(|(variant, _, kind)| (path_names_to_string(variant), kind))
@@ -1802,8 +1802,9 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                     CtorKind::Fictive => format!("({} {{}})", variant),
                 })
                 .collect::<Vec<_>>();
+            let no_suggestable_variant = suggestable_variants.is_empty();
 
-            if !suggestable_variants.is_empty() {
+            if !no_suggestable_variant {
                 let msg = if suggestable_variants.len() == 1 {
                     "you might have meant to use the following enum variant"
                 } else {
@@ -1813,7 +1814,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                 err.span_suggestions(
                     span,
                     msg,
-                    suggestable_variants.drain(..),
+                    suggestable_variants.into_iter(),
                     Applicability::MaybeIncorrect,
                 );
             }
@@ -1830,15 +1831,15 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                 .collect::<Vec<_>>();
 
             if !suggestable_variants_with_placeholders.is_empty() {
-                let msg = match (
+                let msg =
-                    suggestable_variants.is_empty(),
+                    match (no_suggestable_variant, suggestable_variants_with_placeholders.len()) {
-                    suggestable_variants_with_placeholders.len(),
+                        (true, 1) => "the following enum variant is available",
-                ) {
+                        (true, _) => "the following enum variants are available",
-                    (true, 1) => "the following enum variant is available",
+                        (false, 1) => "alternatively, the following enum variant is available",
-                    (true, _) => "the following enum variants are available",
+                        (false, _) => {
-                    (false, 1) => "alternatively, the following enum variant is available",
+                            "alternatively, the following enum variants are also available"
-                    (false, _) => "alternatively, the following enum variants are also available",
+                        }
-                };
+                    };
 
                 err.span_suggestions(
                     span,

compiler/rustc_typeck/src/check/writeback.rs

@@ -501,7 +501,7 @@ impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> {
 
         if !errors_buffer.is_empty() {
             errors_buffer.sort_by_key(|diag| diag.span.primary_span());
-            for mut diag in errors_buffer.drain(..) {
+            for mut diag in errors_buffer {
                 self.tcx().sess.diagnostic().emit_diagnostic(&mut diag);
             }
         }

compiler/rustc_typeck/src/structured_errors/wrong_number_of_generic_args.rs

@@ -523,6 +523,7 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> {
                 if self.not_enough_args_provided() {
                     self.suggest_adding_args(err);
                 } else if self.too_many_args_provided() {
+                    self.suggest_moving_args_from_assoc_fn_to_trait(err);
                     self.suggest_removing_args_or_generics(err);
                 } else {
                     unreachable!();
@@ -653,6 +654,123 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> {
         }
     }
 
+    /// Suggests moving redundant argument(s) of an associate function to the
+    /// trait it belongs to.
+    ///
+    /// ```compile_fail
+    /// Into::into::<Option<_>>(42) // suggests considering `Into::<Option<_>>::into(42)`
+    /// ```
+    fn suggest_moving_args_from_assoc_fn_to_trait(&self, err: &mut Diagnostic) {
+        let trait_ = match self.tcx.trait_of_item(self.def_id) {
+            Some(def_id) => def_id,
+            None => return,
+        };
+
+        // Skip suggestion when the associated function is itself generic, it is unclear
+        // how to split the provided parameters between those to suggest to the trait and
+        // those to remain on the associated type.
+        let num_assoc_fn_expected_args =
+            self.num_expected_type_or_const_args() + self.num_expected_lifetime_args();
+        if num_assoc_fn_expected_args > 0 {
+            return;
+        }
+
+        let num_assoc_fn_excess_args =
+            self.num_excess_type_or_const_args() + self.num_excess_lifetime_args();
+
+        let trait_generics = self.tcx.generics_of(trait_);
+        let num_trait_generics_except_self =
+            trait_generics.count() - if trait_generics.has_self { 1 } else { 0 };
+
+        let msg = format!(
+            "consider moving {these} generic argument{s} to the `{name}` trait, which takes up to {num} argument{s}",
+            these = pluralize!("this", num_assoc_fn_excess_args),
+            s = pluralize!(num_assoc_fn_excess_args),
+            name = self.tcx.item_name(trait_),
+            num = num_trait_generics_except_self,
+        );
+
+        if let Some(hir_id) = self.path_segment.hir_id
+        && let Some(parent_node) = self.tcx.hir().find_parent_node(hir_id)
+        && let Some(parent_node) = self.tcx.hir().find(parent_node)
+        && let hir::Node::Expr(expr) = parent_node {
+            match expr.kind {
+                hir::ExprKind::Path(ref qpath) => {
+                    self.suggest_moving_args_from_assoc_fn_to_trait_for_qualified_path(
+                        err,
+                        qpath,
+                        msg,
+                        num_assoc_fn_excess_args,
+                        num_trait_generics_except_self
+                    )
+                },
+                hir::ExprKind::MethodCall(..) => {
+                    self.suggest_moving_args_from_assoc_fn_to_trait_for_method_call(
+                        err,
+                        trait_,
+                        expr,
+                        msg,
+                        num_assoc_fn_excess_args,
+                        num_trait_generics_except_self
+                    )
+                },
+                _ => return,
+            }
+        }
+    }
+
+    fn suggest_moving_args_from_assoc_fn_to_trait_for_qualified_path(
+        &self,
+        err: &mut Diagnostic,
+        qpath: &'tcx hir::QPath<'tcx>,
+        msg: String,
+        num_assoc_fn_excess_args: usize,
+        num_trait_generics_except_self: usize,
+    ) {
+        if let hir::QPath::Resolved(_, path) = qpath
+        && let Some(trait_path_segment) = path.segments.get(0) {
+            let num_generic_args_supplied_to_trait = trait_path_segment.args().num_generic_params();
+
+            if num_assoc_fn_excess_args == num_trait_generics_except_self - num_generic_args_supplied_to_trait {
+                if let Some(span) = self.gen_args.span_ext()
+                && let Ok(snippet) = self.tcx.sess.source_map().span_to_snippet(span) {
+                    let sugg = vec![
+                        (self.path_segment.ident.span, format!("{}::{}", snippet, self.path_segment.ident)),
+                        (span.with_lo(self.path_segment.ident.span.hi()), "".to_owned())
+                    ];
+
+                    err.multipart_suggestion(
+                        msg,
+                        sugg,
+                        Applicability::MaybeIncorrect
+                    );
+                }
+            }
+        }
+    }
+
+    fn suggest_moving_args_from_assoc_fn_to_trait_for_method_call(
+        &self,
+        err: &mut Diagnostic,
+        trait_: DefId,
+        expr: &'tcx hir::Expr<'tcx>,
+        msg: String,
+        num_assoc_fn_excess_args: usize,
+        num_trait_generics_except_self: usize,
+    ) {
+        if let hir::ExprKind::MethodCall(_, args, _) = expr.kind {
+            assert_eq!(args.len(), 1);
+            if num_assoc_fn_excess_args == num_trait_generics_except_self {
+                if let Some(gen_args) = self.gen_args.span_ext()
+                && let Ok(gen_args) = self.tcx.sess.source_map().span_to_snippet(gen_args)
+                && let Ok(args) = self.tcx.sess.source_map().span_to_snippet(args[0].span) {
+                    let sugg = format!("{}::{}::{}({})", self.tcx.item_name(trait_), gen_args, self.tcx.item_name(self.def_id), args);
+                    err.span_suggestion(expr.span, msg, sugg, Applicability::MaybeIncorrect);
+                }
+            }
+        }
+    }
+
     /// Suggests to remove redundant argument(s):
     ///
     /// ```text

library/core/src/macros/mod.rs

@@ -350,10 +350,12 @@ macro_rules! matches {
 
 /// Unwraps a result or propagates its error.
 ///
-/// The `?` operator was added to replace `try!` and should be used instead.
+/// The [`?` operator][propagating-errors] was added to replace `try!`
-/// Furthermore, `try` is a reserved word in Rust 2018, so if you must use
+/// and should be used instead. Furthermore, `try` is a reserved word
-/// it, you will need to use the [raw-identifier syntax][ris]: `r#try`.
+/// in Rust 2018, so if you must use it, you will need to use the
+/// [raw-identifier syntax][ris]: `r#try`.
 ///
+/// [propagating-errors]: https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html#a-shortcut-for-propagating-errors-the--operator
 /// [ris]: https://doc.rust-lang.org/nightly/rust-by-example/compatibility/raw_identifiers.html
 ///
 /// `try!` matches the given [`Result`]. In case of the `Ok` variant, the

library/std/src/sys/windows/fs.rs

@@ -3,7 +3,7 @@ use crate::os::windows::prelude::*;
 use crate::ffi::OsString;
 use crate::fmt;
 use crate::io::{self, BorrowedCursor, Error, IoSlice, IoSliceMut, SeekFrom};
-use crate::mem;
+use crate::mem::{self, MaybeUninit};
 use crate::os::windows::io::{AsHandle, BorrowedHandle};
 use crate::path::{Path, PathBuf};
 use crate::ptr;
@@ -326,7 +326,8 @@ impl File {
             cvt(c::GetFileInformationByHandle(self.handle.as_raw_handle(), &mut info))?;
             let mut reparse_tag = 0;
             if info.dwFileAttributes & c::FILE_ATTRIBUTE_REPARSE_POINT != 0 {
-                let mut b = Align8([0u8; c::MAXIMUM_REPARSE_DATA_BUFFER_SIZE]);
+                let mut b =
+                    Align8([MaybeUninit::<u8>::uninit(); c::MAXIMUM_REPARSE_DATA_BUFFER_SIZE]);
                 if let Ok((_, buf)) = self.reparse_point(&mut b) {
                     reparse_tag = (*buf).ReparseTag;
                 }
@@ -389,7 +390,8 @@ impl File {
             attr.file_size = info.AllocationSize as u64;
             attr.number_of_links = Some(info.NumberOfLinks);
             if attr.file_type().is_reparse_point() {
-                let mut b = Align8([0; c::MAXIMUM_REPARSE_DATA_BUFFER_SIZE]);
+                let mut b =
+                    Align8([MaybeUninit::<u8>::uninit(); c::MAXIMUM_REPARSE_DATA_BUFFER_SIZE]);
                 if let Ok((_, buf)) = self.reparse_point(&mut b) {
                     attr.reparse_tag = (*buf).ReparseTag;
                 }
@@ -463,7 +465,7 @@ impl File {
     // avoid narrowing provenance to the actual `REPARSE_DATA_BUFFER`.
     fn reparse_point(
         &self,
-        space: &mut Align8<[u8]>,
+        space: &mut Align8<[MaybeUninit<u8>]>,
     ) -> io::Result<(c::DWORD, *const c::REPARSE_DATA_BUFFER)> {
         unsafe {
             let mut bytes = 0;
@@ -488,7 +490,7 @@ impl File {
     }
 
     fn readlink(&self) -> io::Result<PathBuf> {
-        let mut space = Align8([0u8; c::MAXIMUM_REPARSE_DATA_BUFFER_SIZE]);
+        let mut space = Align8([MaybeUninit::<u8>::uninit(); c::MAXIMUM_REPARSE_DATA_BUFFER_SIZE]);
         let (_bytes, buf) = self.reparse_point(&mut space)?;
         unsafe {
             let (path_buffer, subst_off, subst_len, relative) = match (*buf).ReparseTag {
@@ -658,12 +660,16 @@ impl File {
 
 /// A buffer for holding directory entries.
 struct DirBuff {
-    buffer: Box<Align8<[u8; Self::BUFFER_SIZE]>>,
+    buffer: Box<Align8<[MaybeUninit<u8>; Self::BUFFER_SIZE]>>,
 }
 impl DirBuff {
     const BUFFER_SIZE: usize = 1024;
     fn new() -> Self {
-        Self { buffer: Box::new(Align8([0u8; Self::BUFFER_SIZE])) }
+        Self {
+            // Safety: `Align8<[MaybeUninit<u8>; N]>` does not need
+            // initialization.
+            buffer: unsafe { Box::new_uninit().assume_init() },
+        }
     }
     fn capacity(&self) -> usize {
         self.buffer.0.len()
@@ -676,8 +682,8 @@ impl DirBuff {
         DirBuffIter::new(self)
     }
 }
-impl AsRef<[u8]> for DirBuff {
+impl AsRef<[MaybeUninit<u8>]> for DirBuff {
-    fn as_ref(&self) -> &[u8] {
+    fn as_ref(&self) -> &[MaybeUninit<u8>] {
         &self.buffer.0
     }
 }
@@ -686,7 +692,7 @@ impl AsRef<[u8]> for DirBuff {
 ///
 /// Currently only returns file names (UTF-16 encoded).
 struct DirBuffIter<'a> {
-    buffer: Option<&'a [u8]>,
+    buffer: Option<&'a [MaybeUninit<u8>]>,
     cursor: usize,
 }
 impl<'a> DirBuffIter<'a> {
@@ -701,9 +707,13 @@ impl<'a> Iterator for DirBuffIter<'a> {
         let buffer = &self.buffer?[self.cursor..];
 
         // Get the name and next entry from the buffer.
-        // SAFETY: The buffer contains a `FILE_ID_BOTH_DIR_INFO` struct but the
+        // SAFETY:
-        // last field (the file name) is unsized. So an offset has to be
+        // - The buffer contains a `FILE_ID_BOTH_DIR_INFO` struct but the last
-        // used to get the file name slice.
+        //   field (the file name) is unsized. So an offset has to be used to
+        //   get the file name slice.
+        // - The OS has guaranteed initialization of the fields of
+        //   `FILE_ID_BOTH_DIR_INFO` and the trailing filename (for at least
+        //   `FileNameLength` bytes)
         let (name, is_directory, next_entry) = unsafe {
             let info = buffer.as_ptr().cast::<c::FILE_ID_BOTH_DIR_INFO>();
             // Guaranteed to be aligned in documentation for
@@ -1349,7 +1359,7 @@ fn symlink_junction_inner(original: &Path, junction: &Path) -> io::Result<()> {
     let h = f.as_inner().as_raw_handle();
 
     unsafe {
-        let mut data = Align8([0u8; c::MAXIMUM_REPARSE_DATA_BUFFER_SIZE]);
+        let mut data = Align8([MaybeUninit::<u8>::uninit(); c::MAXIMUM_REPARSE_DATA_BUFFER_SIZE]);
         let data_ptr = data.0.as_mut_ptr();
         let db = data_ptr.cast::<c::REPARSE_MOUNTPOINT_DATA_BUFFER>();
         let buf = ptr::addr_of_mut!((*db).ReparseTarget).cast::<c::WCHAR>();

src/doc/rustc/src/platform-support/wasm64-unknown-unknown.md

@@ -30,7 +30,7 @@ is 8-bytes large as well as pointers. The tradeoff, though, is that the maximum
 memory size is now the full 64-bit address space instead of the 4GB as limited
 by the 32-bit address space for `wasm32-unknown-unknown`.
 
-This target is not a stable target. The [memory64] WebAssembly proposal is stil
+This target is not a stable target. The [memory64] WebAssembly proposal is still
 in-progress and not standardized. This means that there are not many engines
 which implement the `memory64` feature and if they do they're likely behind a
 flag, for example:

src/test/ui-fulldeps/internal-lints/diagnostics.rs

@@ -1,6 +1,7 @@
 // compile-flags: -Z unstable-options
 
 #![crate_type = "lib"]
+#![feature(rustc_attrs)]
 #![feature(rustc_private)]
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
@@ -71,3 +72,10 @@ pub fn make_diagnostics<'a>(sess: &'a ParseSess) {
     //~^ ERROR diagnostics should only be created in `SessionDiagnostic`/`AddSubdiagnostic` impls
     //~^^ ERROR diagnostics should be created using translatable messages
 }
+
+// Check that `rustc_lint_diagnostics`-annotated functions aren't themselves linted.
+
+#[rustc_lint_diagnostics]
+pub fn skipped_because_of_annotation<'a>(sess: &'a ParseSess) {
+    let _diag = sess.struct_err("untranslatable diagnostic"); // okay!
+}

src/test/ui-fulldeps/internal-lints/diagnostics.stderr

@@ -1,41 +1,41 @@
 error: diagnostics should be created using translatable messages
-  --> $DIR/diagnostics.rs:36:14
+  --> $DIR/diagnostics.rs:37:14
    |
 LL |         sess.struct_err("untranslatable diagnostic")
    |              ^^^^^^^^^^
    |
 note: the lint level is defined here
-  --> $DIR/diagnostics.rs:5:9
+  --> $DIR/diagnostics.rs:6:9
    |
 LL | #![deny(rustc::untranslatable_diagnostic)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: diagnostics should be created using translatable messages
-  --> $DIR/diagnostics.rs:53:14
+  --> $DIR/diagnostics.rs:54:14
    |
 LL |         diag.note("untranslatable diagnostic");
    |              ^^^^
 
 error: diagnostics should only be created in `SessionDiagnostic`/`AddSubdiagnostic` impls
-  --> $DIR/diagnostics.rs:67:22
+  --> $DIR/diagnostics.rs:68:22
    |
 LL |     let _diag = sess.struct_err(fluent::parser::expect_path);
    |                      ^^^^^^^^^^
    |
 note: the lint level is defined here
-  --> $DIR/diagnostics.rs:6:9
+  --> $DIR/diagnostics.rs:7:9
    |
 LL | #![deny(rustc::diagnostic_outside_of_impl)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: diagnostics should only be created in `SessionDiagnostic`/`AddSubdiagnostic` impls
-  --> $DIR/diagnostics.rs:70:22
+  --> $DIR/diagnostics.rs:71:22
    |
 LL |     let _diag = sess.struct_err("untranslatable diagnostic");
    |                      ^^^^^^^^^^
 
 error: diagnostics should be created using translatable messages
-  --> $DIR/diagnostics.rs:70:22
+  --> $DIR/diagnostics.rs:71:22
    |
 LL |     let _diag = sess.struct_err("untranslatable diagnostic");
    |                      ^^^^^^^^^^

src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.rs

@@ -167,8 +167,8 @@ enum P {
 #[derive(SessionSubdiagnostic)]
 enum Q {
     #[bar]
-    //~^ ERROR `#[bar]` is not a valid attribute
+//~^ ERROR `#[bar]` is not a valid attribute
-    //~^^ ERROR cannot find attribute `bar` in this scope
+//~^^ ERROR cannot find attribute `bar` in this scope
     A {
         #[primary_span]
         span: Span,
@@ -179,8 +179,8 @@ enum Q {
 #[derive(SessionSubdiagnostic)]
 enum R {
     #[bar = "..."]
-    //~^ ERROR `#[bar = ...]` is not a valid attribute
+//~^ ERROR `#[bar = ...]` is not a valid attribute
-    //~^^ ERROR cannot find attribute `bar` in this scope
+//~^^ ERROR cannot find attribute `bar` in this scope
     A {
         #[primary_span]
         span: Span,
@@ -191,8 +191,8 @@ enum R {
 #[derive(SessionSubdiagnostic)]
 enum S {
     #[bar = 4]
-    //~^ ERROR `#[bar = ...]` is not a valid attribute
+//~^ ERROR `#[bar = ...]` is not a valid attribute
-    //~^^ ERROR cannot find attribute `bar` in this scope
+//~^^ ERROR cannot find attribute `bar` in this scope
     A {
         #[primary_span]
         span: Span,
@@ -203,8 +203,8 @@ enum S {
 #[derive(SessionSubdiagnostic)]
 enum T {
     #[bar("...")]
-    //~^ ERROR `#[bar(...)]` is not a valid attribute
+//~^ ERROR `#[bar("...")]` is not a valid attribute
-    //~^^ ERROR cannot find attribute `bar` in this scope
+//~^^ ERROR cannot find attribute `bar` in this scope
     A {
         #[primary_span]
         span: Span,
@@ -215,7 +215,7 @@ enum T {
 #[derive(SessionSubdiagnostic)]
 enum U {
     #[label(code = "...")]
-    //~^ ERROR diagnostic slug must be first argument of a `#[label(...)]` attribute
+//~^ ERROR diagnostic slug must be first argument of a `#[label(...)]` attribute
     A {
         #[primary_span]
         span: Span,
@@ -232,7 +232,7 @@ enum V {
         var: String,
     },
     B {
-    //~^ ERROR subdiagnostic kind not specified
+//~^ ERROR subdiagnostic kind not specified
         #[primary_span]
         span: Span,
         var: String,
@@ -307,16 +307,6 @@ union AC {
     b: u64
 }
 
-#[derive(SessionSubdiagnostic)]
-#[label(parser::add_paren)]
-//~^ NOTE previously specified here
-#[label(parser::add_paren)]
-//~^ ERROR specified multiple times
-struct AD {
-    #[primary_span]
-    span: Span,
-}
-
 #[derive(SessionSubdiagnostic)]
 #[label(parser::add_paren, parser::add_paren)]
 //~^ ERROR `#[label(parser::add_paren)]` is not a valid attribute
@@ -329,16 +319,16 @@ struct AE {
 #[label(parser::add_paren)]
 struct AF {
     #[primary_span]
-    //~^ NOTE previously specified here
+//~^ NOTE previously specified here
     span_a: Span,
     #[primary_span]
-    //~^ ERROR specified multiple times
+//~^ ERROR specified multiple times
     span_b: Span,
 }
 
 #[derive(SessionSubdiagnostic)]
 struct AG {
-    //~^ ERROR subdiagnostic kind not specified
+//~^ ERROR subdiagnostic kind not specified
     #[primary_span]
     span: Span,
 }
@@ -390,25 +380,27 @@ struct AK {
     #[primary_span]
     span: Span,
     #[applicability]
-    //~^ NOTE previously specified here
+//~^ NOTE previously specified here
     applicability_a: Applicability,
     #[applicability]
-    //~^ ERROR specified multiple times
+//~^ ERROR specified multiple times
     applicability_b: Applicability,
 }
 
 #[derive(SessionSubdiagnostic)]
 #[suggestion(parser::add_paren, code = "...")]
+//~^ ERROR suggestion without `applicability`
 struct AL {
     #[primary_span]
     span: Span,
     #[applicability]
-    //~^ ERROR the `#[applicability]` attribute can only be applied to fields of type `Applicability`
+//~^ ERROR the `#[applicability]` attribute can only be applied to fields of type `Applicability`
     applicability: Span,
 }
 
 #[derive(SessionSubdiagnostic)]
 #[suggestion(parser::add_paren, code = "...")]
+//~^ ERROR suggestion without `applicability`
 struct AM {
     #[primary_span]
     span: Span,
@@ -444,7 +436,8 @@ struct AQ;
 
 #[derive(SessionSubdiagnostic)]
 #[suggestion(parser::add_paren, code = "...")]
-//~^ ERROR suggestion without `#[primary_span]` field
+//~^ ERROR suggestion without `applicability`
+//~^^ ERROR suggestion without `#[primary_span]` field
 struct AR {
     var: String,
 }
@@ -514,120 +507,3 @@ struct AZ {
     #[primary_span]
     span: Span,
 }
-
-#[derive(SessionSubdiagnostic)]
-#[suggestion(parser::add_paren, code = "...")]
-//~^ ERROR suggestion without `#[primary_span]` field
-struct BA {
-    #[suggestion_part]
-    //~^ ERROR `#[suggestion_part]` is not a valid attribute
-    span: Span,
-    #[suggestion_part(code = "...")]
-    //~^ ERROR `#[suggestion_part(...)]` is not a valid attribute
-    span2: Span,
-    #[applicability]
-    applicability: Applicability,
-    var: String,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren, code = "...", applicability = "machine-applicable")]
-//~^ ERROR multipart suggestion without any `#[suggestion_part(...)]` fields
-//~| ERROR `code` is not a valid nested attribute of a `multipart_suggestion` attribute
-struct BBa {
-    var: String,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren, applicability = "machine-applicable")]
-struct BBb {
-    #[suggestion_part]
-    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
-    span1: Span,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren, applicability = "machine-applicable")]
-struct BBc {
-    #[suggestion_part()]
-    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
-    span1: Span,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren)]
-//~^ ERROR multipart suggestion without any `#[suggestion_part(...)]` fields
-struct BC {
-    #[primary_span]
-    //~^ ERROR `#[primary_span]` is not a valid attribute
-    span: Span,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren)]
-struct BD {
-    #[suggestion_part]
-    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
-    span1: Span,
-    #[suggestion_part()]
-    //~^ ERROR `#[suggestion_part(...)]` attribute without `code = "..."`
-    span2: Span,
-    #[suggestion_part(foo = "bar")]
-    //~^ ERROR `#[suggestion_part(foo = ...)]` is not a valid attribute
-    span4: Span,
-    #[suggestion_part(code = "...")]
-    //~^ ERROR the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-    s1: String,
-    #[suggestion_part()]
-    //~^ ERROR the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-    s2: String,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren, applicability = "machine-applicable")]
-struct BE {
-    #[suggestion_part(code = "...", code = ",,,")]
-    //~^ ERROR specified multiple times
-    //~| NOTE previously specified here
-    span: Span,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren, applicability = "machine-applicable")]
-struct BF {
-    #[suggestion_part(code = "(")]
-    first: Span,
-    #[suggestion_part(code = ")")]
-    second: Span,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren)]
-struct BG {
-    #[applicability]
-    appl: Applicability,
-    #[suggestion_part(code = "(")]
-    first: Span,
-    #[suggestion_part(code = ")")]
-    second: Span,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren, applicability = "machine-applicable")]
-//~^ NOTE previously specified here
-struct BH {
-    #[applicability]
-    //~^ ERROR specified multiple times
-    appl: Applicability,
-    #[suggestion_part(code = "(")]
-    first: Span,
-    #[suggestion_part(code = ")")]
-    second: Span,
-}
-
-#[derive(SessionSubdiagnostic)]
-#[multipart_suggestion(parser::add_paren, applicability = "machine-applicable")]
-struct BI {
-    #[suggestion_part(code = "")]
-    spans: Vec<Span>,
-}

src/test/ui-fulldeps/session-diagnostic/subdiagnostic-derive.stderr

@@ -65,16 +65,16 @@ LL | #[label()]
    | ^^^^^^^^^^
 
 error: `code` is not a valid nested attribute of a `label` attribute
-  --> $DIR/subdiagnostic-derive.rs:137:28
+  --> $DIR/subdiagnostic-derive.rs:137:1
    |
 LL | #[label(parser::add_paren, code = "...")]
-   |                            ^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `applicability` is not a valid nested attribute of a `label` attribute
-  --> $DIR/subdiagnostic-derive.rs:146:28
+  --> $DIR/subdiagnostic-derive.rs:146:1
    |
 LL | #[label(parser::add_paren, applicability = "machine-applicable")]
-   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: unsupported type attribute for subdiagnostic enum
   --> $DIR/subdiagnostic-derive.rs:155:1
@@ -100,11 +100,13 @@ error: `#[bar = ...]` is not a valid attribute
 LL |     #[bar = 4]
    |     ^^^^^^^^^^
 
-error: `#[bar(...)]` is not a valid attribute
+error: `#[bar("...")]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:205:5
+  --> $DIR/subdiagnostic-derive.rs:205:11
    |
 LL |     #[bar("...")]
-   |     ^^^^^^^^^^^^^
+   |           ^^^^^
+   |
+   = help: first argument of the attribute should be the diagnostic slug
 
 error: diagnostic slug must be first argument of a `#[label(...)]` attribute
   --> $DIR/subdiagnostic-derive.rs:217:5
@@ -161,8 +163,6 @@ error: `#[bar(...)]` is not a valid attribute
    |
 LL |     #[bar("...")]
    |     ^^^^^^^^^^^^^
-   |
-   = help: only `primary_span`, `applicability` and `skip_arg` are valid field attributes
 
 error: unexpected unsupported untagged union
   --> $DIR/subdiagnostic-derive.rs:304:1
@@ -174,20 +174,8 @@ LL | |     b: u64
 LL | | }
    | |_^
 
-error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:313:1
-   |
-LL | #[label(parser::add_paren)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:311:1
-   |
-LL | #[label(parser::add_paren)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
 error: `#[label(parser::add_paren)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:321:28
+  --> $DIR/subdiagnostic-derive.rs:311:28
    |
 LL | #[label(parser::add_paren, parser::add_paren)]
    |                            ^^^^^^^^^^^^^^^^^
@@ -195,226 +183,134 @@ LL | #[label(parser::add_paren, parser::add_paren)]
    = help: a diagnostic slug must be the first argument to the attribute
 
 error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:334:5
+  --> $DIR/subdiagnostic-derive.rs:324:5
    |
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:331:5
+  --> $DIR/subdiagnostic-derive.rs:321:5
    |
 LL |     #[primary_span]
    |     ^^^^^^^^^^^^^^^
 
 error: subdiagnostic kind not specified
-  --> $DIR/subdiagnostic-derive.rs:340:8
+  --> $DIR/subdiagnostic-derive.rs:330:8
    |
 LL | struct AG {
    |        ^^
 
 error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:377:47
+  --> $DIR/subdiagnostic-derive.rs:367:47
    |
 LL | #[suggestion(parser::add_paren, code = "...", code = "...")]
    |                                               ^^^^^^^^^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:377:33
+  --> $DIR/subdiagnostic-derive.rs:367:33
    |
 LL | #[suggestion(parser::add_paren, code = "...", code = "...")]
    |                                 ^^^^^^^^^^^^
 
 error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:395:5
+  --> $DIR/subdiagnostic-derive.rs:385:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
    |
 note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:392:5
+  --> $DIR/subdiagnostic-derive.rs:382:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
 error: the `#[applicability]` attribute can only be applied to fields of type `Applicability`
-  --> $DIR/subdiagnostic-derive.rs:405:5
+  --> $DIR/subdiagnostic-derive.rs:396:5
    |
 LL |     #[applicability]
    |     ^^^^^^^^^^^^^^^^
 
-error: suggestion without `code = "..."`
+error: suggestion without `applicability`
-  --> $DIR/subdiagnostic-derive.rs:418:1
+  --> $DIR/subdiagnostic-derive.rs:391:1
    |
-LL | #[suggestion(parser::add_paren)]
+LL | / #[suggestion(parser::add_paren, code = "...")]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | |
+LL | | struct AL {
+LL | |     #[primary_span]
+...  |
+LL | |     applicability: Span,
+LL | | }
+   | |_^
+
+error: suggestion without `applicability`
+  --> $DIR/subdiagnostic-derive.rs:402:1
+   |
+LL | / #[suggestion(parser::add_paren, code = "...")]
+LL | |
+LL | | struct AM {
+LL | |     #[primary_span]
+LL | |     span: Span,
+LL | | }
+   | |_^
+
+error: suggestion without `code = "..."`
+  --> $DIR/subdiagnostic-derive.rs:410:1
+   |
+LL | / #[suggestion(parser::add_paren)]
+LL | |
+LL | | struct AN {
+LL | |     #[primary_span]
+...  |
+LL | |     applicability: Applicability,
+LL | | }
+   | |_^
 
 error: invalid applicability
-  --> $DIR/subdiagnostic-derive.rs:428:46
+  --> $DIR/subdiagnostic-derive.rs:420:46
    |
 LL | #[suggestion(parser::add_paren, code ="...", applicability = "foo")]
    |                                              ^^^^^^^^^^^^^^^^^^^^^
 
-error: suggestion without `#[primary_span]` field
+error: suggestion without `applicability`
-  --> $DIR/subdiagnostic-derive.rs:446:1
+  --> $DIR/subdiagnostic-derive.rs:438:1
    |
 LL | / #[suggestion(parser::add_paren, code = "...")]
 LL | |
+LL | |
+LL | | struct AR {
+LL | |     var: String,
+LL | | }
+   | |_^
+
+error: suggestion without `#[primary_span]` field
+  --> $DIR/subdiagnostic-derive.rs:438:1
+   |
+LL | / #[suggestion(parser::add_paren, code = "...")]
+LL | |
+LL | |
 LL | | struct AR {
 LL | |     var: String,
 LL | | }
    | |_^
 
 error: unsupported type attribute for subdiagnostic enum
-  --> $DIR/subdiagnostic-derive.rs:460:1
+  --> $DIR/subdiagnostic-derive.rs:453:1
    |
 LL | #[label]
    | ^^^^^^^^
 
 error: `var` doesn't refer to a field on this type
-  --> $DIR/subdiagnostic-derive.rs:480:39
+  --> $DIR/subdiagnostic-derive.rs:473:39
    |
 LL | #[suggestion(parser::add_paren, code ="{var}", applicability = "machine-applicable")]
    |                                       ^^^^^^^
 
 error: `var` doesn't refer to a field on this type
-  --> $DIR/subdiagnostic-derive.rs:499:43
+  --> $DIR/subdiagnostic-derive.rs:492:43
    |
 LL |     #[suggestion(parser::add_paren, code ="{var}", applicability = "machine-applicable")]
    |                                           ^^^^^^^
 
-error: `#[suggestion_part]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:522:5
-   |
-LL |     #[suggestion_part]
-   |     ^^^^^^^^^^^^^^^^^^
-   |
-   = help: `#[suggestion_part(...)]` is only valid in multipart suggestions, use `#[primary_span]` instead
-
-error: `#[suggestion_part(...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:525:5
-   |
-LL |     #[suggestion_part(code = "...")]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = help: `#[suggestion_part(...)]` is only valid in multipart suggestions
-
-error: suggestion without `#[primary_span]` field
-  --> $DIR/subdiagnostic-derive.rs:519:1
-   |
-LL | / #[suggestion(parser::add_paren, code = "...")]
-LL | |
-LL | | struct BA {
-LL | |     #[suggestion_part]
-...  |
-LL | |     var: String,
-LL | | }
-   | |_^
-
-error: `code` is not a valid nested attribute of a `multipart_suggestion` attribute
-  --> $DIR/subdiagnostic-derive.rs:534:43
-   |
-LL | #[multipart_suggestion(parser::add_paren, code = "...", applicability = "machine-applicable")]
-   |                                           ^^^^^^^^^^^^
-
-error: multipart suggestion without any `#[suggestion_part(...)]` fields
-  --> $DIR/subdiagnostic-derive.rs:534:1
-   |
-LL | / #[multipart_suggestion(parser::add_paren, code = "...", applicability = "machine-applicable")]
-LL | |
-LL | |
-LL | | struct BBa {
-LL | |     var: String,
-LL | | }
-   | |_^
-
-error: `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:544:5
-   |
-LL |     #[suggestion_part]
-   |     ^^^^^^^^^^^^^^^^^^
-
-error: `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:552:5
-   |
-LL |     #[suggestion_part()]
-   |     ^^^^^^^^^^^^^^^^^^^^
-
-error: `#[primary_span]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:561:5
-   |
-LL |     #[primary_span]
-   |     ^^^^^^^^^^^^^^^
-   |
-   = help: multipart suggestions use one or more `#[suggestion_part]`s rather than one `#[primary_span]`
-
-error: multipart suggestion without any `#[suggestion_part(...)]` fields
-  --> $DIR/subdiagnostic-derive.rs:558:1
-   |
-LL | / #[multipart_suggestion(parser::add_paren)]
-LL | |
-LL | | struct BC {
-LL | |     #[primary_span]
-LL | |
-LL | |     span: Span,
-LL | | }
-   | |_^
-
-error: `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:569:5
-   |
-LL |     #[suggestion_part]
-   |     ^^^^^^^^^^^^^^^^^^
-
-error: `#[suggestion_part(...)]` attribute without `code = "..."`
-  --> $DIR/subdiagnostic-derive.rs:572:5
-   |
-LL |     #[suggestion_part()]
-   |     ^^^^^^^^^^^^^^^^^^^^
-
-error: `#[suggestion_part(foo = ...)]` is not a valid attribute
-  --> $DIR/subdiagnostic-derive.rs:575:23
-   |
-LL |     #[suggestion_part(foo = "bar")]
-   |                       ^^^^^^^^^^^
-   |
-   = help: `code` is the only valid nested attribute
-
-error: the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-  --> $DIR/subdiagnostic-derive.rs:578:5
-   |
-LL |     #[suggestion_part(code = "...")]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-error: the `#[suggestion_part(...)]` attribute can only be applied to fields of type `Span` or `MultiSpan`
-  --> $DIR/subdiagnostic-derive.rs:581:5
-   |
-LL |     #[suggestion_part()]
-   |     ^^^^^^^^^^^^^^^^^^^^
-
-error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:589:37
-   |
-LL |     #[suggestion_part(code = "...", code = ",,,")]
-   |                                     ^^^^^^^^^^^^
-   |
-note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:589:23
-   |
-LL |     #[suggestion_part(code = "...", code = ",,,")]
-   |                       ^^^^^^^^^^^^
-
-error: specified multiple times
-  --> $DIR/subdiagnostic-derive.rs:619:5
-   |
-LL |     #[applicability]
-   |     ^^^^^^^^^^^^^^^^
-   |
-note: previously specified here
-  --> $DIR/subdiagnostic-derive.rs:616:43
-   |
-LL | #[multipart_suggestion(parser::add_paren, applicability = "machine-applicable")]
-   |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
 error: cannot find attribute `foo` in this scope
   --> $DIR/subdiagnostic-derive.rs:63:3
    |
@@ -475,6 +371,6 @@ error[E0425]: cannot find value `slug` in module `rustc_errors::fluent`
 LL | #[label(slug)]
    |         ^^^^ not found in `rustc_errors::fluent`
 
-error: aborting due to 64 previous errors
+error: aborting due to 50 previous errors
 
 For more information about this error, try `rustc --explain E0425`.

src/test/ui/const-generics/invalid-const-arg-for-type-param.stderr

@@ -2,15 +2,22 @@ error[E0107]: this associated function takes 0 generic arguments but 1 generic a
   --> $DIR/invalid-const-arg-for-type-param.rs:6:23
    |
 LL |     let _: u32 = 5i32.try_into::<32>().unwrap();
-   |                       ^^^^^^^^------ help: remove these generics
+   |                       ^^^^^^^^ expected 0 generic arguments
-   |                       |
-   |                       expected 0 generic arguments
    |
 note: associated function defined here, with 0 generic parameters
   --> $SRC_DIR/core/src/convert/mod.rs:LL:COL
    |
 LL |     fn try_into(self) -> Result<T, Self::Error>;
    |        ^^^^^^^^
+help: consider moving this generic argument to the `TryInto` trait, which takes up to 1 argument
+   |
+LL |     let _: u32 = TryInto::<32>::try_into(5i32).unwrap();
+   |                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+help: remove these generics
+   |
+LL -     let _: u32 = 5i32.try_into::<32>().unwrap();
+LL +     let _: u32 = 5i32.try_into().unwrap();
+   |
 
 error[E0599]: no method named `f` found for struct `S` in the current scope
   --> $DIR/invalid-const-arg-for-type-param.rs:9:7

src/test/ui/resolve/issue-73427.rs

@@ -22,6 +22,10 @@ enum D {
     Unit,
 }
 
+enum E {
+    TupleWithFields(()),
+}
+
 fn main() {
     // Only variants without fields are suggested (and others mentioned in a note) where an enum
     // is used rather than a variant.
@@ -34,6 +38,8 @@ fn main() {
     //~^ ERROR expected value, found enum `C`
     D.foo();
     //~^ ERROR expected value, found enum `D`
+    E.foo();
+    //~^ ERROR expected value, found enum `E`
 
     // Only tuple variants are suggested in calls or tuple struct pattern matching.
 

src/test/ui/resolve/issue-73427.stderr

@@ -1,5 +1,5 @@
 error[E0423]: expected value, found enum `A`
-  --> $DIR/issue-73427.rs:29:5
+  --> $DIR/issue-73427.rs:33:5
    |
 LL |     A.foo();
    |     ^
@@ -23,7 +23,7 @@ LL |     (A::Tuple()).foo();
    |     ~~~~~~~~~~~~
 LL |     A::Unit.foo();
    |     ~~~~~~~
-help: the following enum variants are available
+help: alternatively, the following enum variants are also available
    |
 LL |     (A::StructWithFields { /* fields */ }).foo();
    |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -31,7 +31,7 @@ LL |     (A::TupleWithFields(/* fields */)).foo();
    |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 error[E0423]: expected value, found enum `B`
-  --> $DIR/issue-73427.rs:31:5
+  --> $DIR/issue-73427.rs:35:5
    |
 LL |     B.foo();
    |     ^
@@ -52,7 +52,7 @@ LL |     (B::TupleWithFields(/* fields */)).foo();
    |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 error[E0423]: expected value, found enum `C`
-  --> $DIR/issue-73427.rs:33:5
+  --> $DIR/issue-73427.rs:37:5
    |
 LL |     C.foo();
    |     ^
@@ -70,7 +70,7 @@ help: you might have meant to use the following enum variant
    |
 LL |     C::Unit.foo();
    |     ~~~~~~~
-help: the following enum variants are available
+help: alternatively, the following enum variants are also available
    |
 LL |     (C::StructWithFields { /* fields */ }).foo();
    |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -78,7 +78,7 @@ LL |     (C::TupleWithFields(/* fields */)).foo();
    |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 error[E0423]: expected value, found enum `D`
-  --> $DIR/issue-73427.rs:35:5
+  --> $DIR/issue-73427.rs:39:5
    |
 LL |     D.foo();
    |     ^
@@ -95,13 +95,37 @@ help: you might have meant to use the following enum variant
    |
 LL |     D::Unit.foo();
    |     ~~~~~~~
-help: the following enum variant is available
+help: alternatively, the following enum variant is available
    |
 LL |     (D::TupleWithFields(/* fields */)).foo();
    |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
+error[E0423]: expected value, found enum `E`
+  --> $DIR/issue-73427.rs:41:5
+   |
+LL |     E.foo();
+   |     ^
+   |
+note: the enum is defined here
+  --> $DIR/issue-73427.rs:25:1
+   |
+LL | / enum E {
+LL | |     TupleWithFields(()),
+LL | | }
+   | |_^
+help: the following enum variant is available
+   |
+LL |     (E::TupleWithFields(/* fields */)).foo();
+   |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+help: consider importing one of these items instead
+   |
+LL | use std::f32::consts::E;
+   |
+LL | use std::f64::consts::E;
+   |
+
 error[E0423]: expected function, tuple struct or tuple variant, found enum `A`
-  --> $DIR/issue-73427.rs:40:13
+  --> $DIR/issue-73427.rs:46:13
    |
 LL |     let x = A(3);
    |             ^
@@ -126,7 +150,7 @@ LL |     let x = A::TupleWithFields(3);
    |             ~~~~~~~~~~~~~~~~~~
 
 error[E0532]: expected tuple struct or tuple variant, found enum `A`
-  --> $DIR/issue-73427.rs:42:12
+  --> $DIR/issue-73427.rs:48:12
    |
 LL |     if let A(3) = x { }
    |            ^
@@ -150,7 +174,7 @@ LL |     if let A::Tuple(3) = x { }
 LL |     if let A::TupleWithFields(3) = x { }
    |            ~~~~~~~~~~~~~~~~~~
 
-error: aborting due to 6 previous errors
+error: aborting due to 7 previous errors
 
 Some errors have detailed explanations: E0423, E0532.
 For more information about an error, try `rustc --explain E0423`.

src/test/ui/resolve/privacy-enum-ctor.stderr

@@ -19,7 +19,7 @@ help: you might have meant to use the following enum variant
    |
 LL |         m::Z::Unit;
    |         ~~~~~~~~~~
-help: the following enum variants are available
+help: alternatively, the following enum variants are also available
    |
 LL |         (m::Z::Fn(/* fields */));
    |         ~~~~~~~~~~~~~~~~~~~~~~~~
@@ -47,7 +47,7 @@ help: you might have meant to use the following enum variant
    |
 LL |         m::Z::Unit;
    |         ~~~~~~~~~~
-help: the following enum variants are available
+help: alternatively, the following enum variants are also available
    |
 LL |         (m::Z::Fn(/* fields */));
    |         ~~~~~~~~~~~~~~~~~~~~~~~~
@@ -89,7 +89,7 @@ help: you might have meant to use the following enum variant
    |
 LL |     let _: E = E::Unit;
    |                ~~~~~~~
-help: the following enum variants are available
+help: alternatively, the following enum variants are also available
    |
 LL |     let _: E = (E::Fn(/* fields */));
    |                ~~~~~~~~~~~~~~~~~~~~~
@@ -143,7 +143,7 @@ help: you might have meant to use the following enum variant
    |
 LL |     let _: E = E::Unit;
    |                ~~~~~~~
-help: the following enum variants are available
+help: alternatively, the following enum variants are also available
    |
 LL |     let _: E = (E::Fn(/* fields */));
    |                ~~~~~~~~~~~~~~~~~~~~~
@@ -203,7 +203,7 @@ help: you might have meant to use the following enum variant
    |
 LL |     let _: Z = m::Z::Unit;
    |                ~~~~~~~~~~
-help: the following enum variants are available
+help: alternatively, the following enum variants are also available
    |
 LL |     let _: Z = (m::Z::Fn(/* fields */));
    |                ~~~~~~~~~~~~~~~~~~~~~~~~

src/test/ui/suggestions/issue-89064.rs

@@ -0,0 +1,35 @@
+use std::convert::TryInto;
+
+trait A<T> {
+    fn foo() {}
+}
+
+trait B<T, U> {
+    fn bar() {}
+}
+
+struct S;
+
+impl<T> A<T> for S {}
+impl<T, U> B<T, U> for S {}
+
+fn main() {
+    let _ = A::foo::<S>();
+    //~^ ERROR
+    //~| HELP remove these generics
+    //~| HELP consider moving this generic argument
+
+    let _ = B::bar::<S, S>();
+    //~^ ERROR
+    //~| HELP remove these generics
+    //~| HELP consider moving these generic arguments
+
+    let _ = A::<S>::foo::<S>();
+    //~^ ERROR
+    //~| HELP remove these generics
+
+    let _ = 42.into::<Option<_>>();
+    //~^ ERROR
+    //~| HELP remove these generics
+    //~| HELP consider moving this generic argument
+}

src/test/ui/suggestions/issue-89064.stderr

@@ -0,0 +1,82 @@
+error[E0107]: this associated function takes 0 generic arguments but 1 generic argument was supplied
+  --> $DIR/issue-89064.rs:17:16
+   |
+LL |     let _ = A::foo::<S>();
+   |                ^^^ expected 0 generic arguments
+   |
+note: associated function defined here, with 0 generic parameters
+  --> $DIR/issue-89064.rs:4:8
+   |
+LL |     fn foo() {}
+   |        ^^^
+help: consider moving this generic argument to the `A` trait, which takes up to 1 argument
+   |
+LL -     let _ = A::foo::<S>();
+LL +     let _ = A::<S>::foo();
+   |
+help: remove these generics
+   |
+LL -     let _ = A::foo::<S>();
+LL +     let _ = A::foo();
+   |
+
+error[E0107]: this associated function takes 0 generic arguments but 2 generic arguments were supplied
+  --> $DIR/issue-89064.rs:22:16
+   |
+LL |     let _ = B::bar::<S, S>();
+   |                ^^^ expected 0 generic arguments
+   |
+note: associated function defined here, with 0 generic parameters
+  --> $DIR/issue-89064.rs:8:8
+   |
+LL |     fn bar() {}
+   |        ^^^
+help: consider moving these generic arguments to the `B` trait, which takes up to 2 arguments
+   |
+LL -     let _ = B::bar::<S, S>();
+LL +     let _ = B::<S, S>::bar();
+   |
+help: remove these generics
+   |
+LL -     let _ = B::bar::<S, S>();
+LL +     let _ = B::bar();
+   |
+
+error[E0107]: this associated function takes 0 generic arguments but 1 generic argument was supplied
+  --> $DIR/issue-89064.rs:27:21
+   |
+LL |     let _ = A::<S>::foo::<S>();
+   |                     ^^^----- help: remove these generics
+   |                     |
+   |                     expected 0 generic arguments
+   |
+note: associated function defined here, with 0 generic parameters
+  --> $DIR/issue-89064.rs:4:8
+   |
+LL |     fn foo() {}
+   |        ^^^
+
+error[E0107]: this associated function takes 0 generic arguments but 1 generic argument was supplied
+  --> $DIR/issue-89064.rs:31:16
+   |
+LL |     let _ = 42.into::<Option<_>>();
+   |                ^^^^ expected 0 generic arguments
+   |
+note: associated function defined here, with 0 generic parameters
+  --> $SRC_DIR/core/src/convert/mod.rs:LL:COL
+   |
+LL |     fn into(self) -> T;
+   |        ^^^^
+help: consider moving this generic argument to the `Into` trait, which takes up to 1 argument
+   |
+LL |     let _ = Into::<Option<_>>::into(42);
+   |             ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+help: remove these generics
+   |
+LL -     let _ = 42.into::<Option<_>>();
+LL +     let _ = 42.into();
+   |
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0107`.

src/test/ui/unpretty/avoid-crash.rs

@@ -0,0 +1,4 @@
+// normalize-stderr-test "error `.*`" -> "$$ERROR_MESSAGE"
+// compile-flags: -o/tmp/ -Zunpretty=ast-tree
+
+fn main() {}

src/test/ui/unpretty/avoid-crash.stderr

@@ -0,0 +1,4 @@
+error: pretty-print failed to write `/tmp/` due to $ERROR_MESSAGE
+
+error: aborting due to previous error
+

src/tools/clippy/.github/workflows/clippy.yml

@@ -24,6 +24,7 @@ env:
   RUST_BACKTRACE: 1
   CARGO_TARGET_DIR: '${{ github.workspace }}/target'
   NO_FMT_TEST: 1
+  CARGO_INCREMENTAL: 0
 
 jobs:
   base:

src/tools/clippy/.github/workflows/clippy_bors.yml

@@ -10,6 +10,7 @@ env:
   RUST_BACKTRACE: 1
   CARGO_TARGET_DIR: '${{ github.workspace }}/target'
   NO_FMT_TEST: 1
+  CARGO_INCREMENTAL: 0
 
 defaults:
   run:

src/tools/clippy/CHANGELOG.md

@@ -6,11 +6,157 @@ document.
 
 ## Unreleased / In Rust Nightly
 
-[7c21f91b...master](https://github.com/rust-lang/rust-clippy/compare/7c21f91b...master)
+[d7b5cbf0...master](https://github.com/rust-lang/rust-clippy/compare/d7b5cbf0...master)
+
+## Rust 1.63
+
+Current stable, released 2022-08-11
+
+[7c21f91b...d7b5cbf0](https://github.com/rust-lang/rust-clippy/compare/7c21f91b...d7b5cbf0)
+
+### New Lints
+
+* [`borrow_deref_ref`]
+  [#7930](https://github.com/rust-lang/rust-clippy/pull/7930)
+* [`doc_link_with_quotes`]
+  [#8385](https://github.com/rust-lang/rust-clippy/pull/8385)
+* [`no_effect_replace`]
+  [#8754](https://github.com/rust-lang/rust-clippy/pull/8754)
+* [`rc_clone_in_vec_init`]
+  [#8769](https://github.com/rust-lang/rust-clippy/pull/8769)
+* [`derive_partial_eq_without_eq`]
+  [#8796](https://github.com/rust-lang/rust-clippy/pull/8796)
+* [`mismatching_type_param_order`]
+  [#8831](https://github.com/rust-lang/rust-clippy/pull/8831)
+* [`duplicate_mod`] [#8832](https://github.com/rust-lang/rust-clippy/pull/8832)
+* [`unused_rounding`]
+  [#8866](https://github.com/rust-lang/rust-clippy/pull/8866)
+* [`get_first`] [#8882](https://github.com/rust-lang/rust-clippy/pull/8882)
+* [`swap_ptr_to_ref`]
+  [#8916](https://github.com/rust-lang/rust-clippy/pull/8916)
+* [`almost_complete_letter_range`]
+  [#8918](https://github.com/rust-lang/rust-clippy/pull/8918)
+* [`needless_parens_on_range_literals`]
+  [#8933](https://github.com/rust-lang/rust-clippy/pull/8933)
+* [`as_underscore`] [#8934](https://github.com/rust-lang/rust-clippy/pull/8934)
+
+### Moves and Deprecations
+
+* Rename `eval_order_dependence` to [`mixed_read_write_in_expression`], move to
+  `nursery` [#8621](https://github.com/rust-lang/rust-clippy/pull/8621)
+
+### Enhancements
+
+* [`undocumented_unsafe_blocks`]: Now also lints on unsafe trait implementations
+  [#8761](https://github.com/rust-lang/rust-clippy/pull/8761)
+* [`empty_line_after_outer_attr`]: Now also lints on argumentless macros
+  [#8790](https://github.com/rust-lang/rust-clippy/pull/8790)
+* [`expect_used`]: Now can be disabled in tests with the `allow-expect-in-tests`
+  option [#8802](https://github.com/rust-lang/rust-clippy/pull/8802)
+* [`unwrap_used`]: Now can be disabled in tests with the `allow-unwrap-in-tests`
+  option [#8802](https://github.com/rust-lang/rust-clippy/pull/8802)
+* [`disallowed_methods`]: Now also lints indirect usages
+  [#8852](https://github.com/rust-lang/rust-clippy/pull/8852)
+* [`get_last_with_len`]: Now also lints `VecDeque` and any deref to slice
+  [#8862](https://github.com/rust-lang/rust-clippy/pull/8862)
+* [`manual_range_contains`]: Now also lints on chains of `&&` and `||`
+  [#8884](https://github.com/rust-lang/rust-clippy/pull/8884)
+* [`rc_clone_in_vec_init`]: Now also lints on `Weak`
+  [#8885](https://github.com/rust-lang/rust-clippy/pull/8885)
+* [`dbg_macro`]: Introduce `allow-dbg-in-tests` config option
+  [#8897](https://github.com/rust-lang/rust-clippy/pull/8897)
+* [`use_self`]: Now also lints on `TupleStruct` and `Struct` patterns
+  [#8899](https://github.com/rust-lang/rust-clippy/pull/8899)
+* [`manual_find_map`] and [`manual_filter_map`]: Now also lints on more complex
+  method chains inside `map`
+  [#8930](https://github.com/rust-lang/rust-clippy/pull/8930)
+* [`needless_return`]: Now also lints on macro expressions in return statements
+  [#8932](https://github.com/rust-lang/rust-clippy/pull/8932)
+* [`doc_markdown`]: Users can now indicate, that the `doc-valid-idents` config
+  should extend the default and not replace it
+  [#8944](https://github.com/rust-lang/rust-clippy/pull/8944)
+* [`disallowed_names`]: Users can now indicate, that the `disallowed-names`
+  config should extend the default and not replace it
+  [#8944](https://github.com/rust-lang/rust-clippy/pull/8944)
+* [`never_loop`]: Now checks for `continue` in struct expression
+  [#9002](https://github.com/rust-lang/rust-clippy/pull/9002)
+
+### False Positive Fixes
+
+* [`useless_transmute`]: No longer lints on types with erased regions
+  [#8564](https://github.com/rust-lang/rust-clippy/pull/8564)
+* [`vec_init_then_push`]: No longer lints when further extended
+  [#8699](https://github.com/rust-lang/rust-clippy/pull/8699)
+* [`cmp_owned`]: No longer lints on `From::from` for `Copy` types
+  [#8807](https://github.com/rust-lang/rust-clippy/pull/8807)
+* [`redundant_allocation`]: No longer lints on fat pointers that would become
+  thin pointers [#8813](https://github.com/rust-lang/rust-clippy/pull/8813)
+* [`derive_partial_eq_without_eq`]:
+    * Handle differing predicates applied by `#[derive(PartialEq)]` and
+      `#[derive(Eq)]`
+      [#8869](https://github.com/rust-lang/rust-clippy/pull/8869)
+    * No longer lints on non-public types and better handles generics
+      [#8950](https://github.com/rust-lang/rust-clippy/pull/8950)
+* [`empty_line_after_outer_attr`]: No longer lints empty lines in inner
+  string values [#8892](https://github.com/rust-lang/rust-clippy/pull/8892)
+* [`branches_sharing_code`]: No longer lints when using different binding names
+  [#8901](https://github.com/rust-lang/rust-clippy/pull/8901)
+* [`significant_drop_in_scrutinee`]: No longer lints on Try `?` and `await`
+  desugared expressions [#8902](https://github.com/rust-lang/rust-clippy/pull/8902)
+* [`checked_conversions`]: No longer lints in `const` contexts
+  [#8907](https://github.com/rust-lang/rust-clippy/pull/8907)
+* [`iter_overeager_cloned`]: No longer lints on `.cloned().flatten()` when
+  `T::Item` doesn't implement `IntoIterator`
+  [#8960](https://github.com/rust-lang/rust-clippy/pull/8960)
+
+### Suggestion Fixes/Improvements
+
+* [`vec_init_then_push`]: Suggest to remove `mut` binding when possible
+  [#8699](https://github.com/rust-lang/rust-clippy/pull/8699)
+* [`manual_range_contains`]: Fix suggestion for integers with different signs
+  [#8763](https://github.com/rust-lang/rust-clippy/pull/8763)
+* [`identity_op`]: Add parenthesis to suggestions where required
+  [#8786](https://github.com/rust-lang/rust-clippy/pull/8786)
+* [`cast_lossless`]: No longer gives wrong suggestion on `usize`/`isize`->`f64`
+  [#8778](https://github.com/rust-lang/rust-clippy/pull/8778)
+* [`rc_clone_in_vec_init`]: Add suggestion
+  [#8814](https://github.com/rust-lang/rust-clippy/pull/8814)
+* The "unknown field" error messages for config files now wraps the field names
+  [#8823](https://github.com/rust-lang/rust-clippy/pull/8823)
+* [`cast_abs_to_unsigned`]: Do not remove cast if it's required
+  [#8876](https://github.com/rust-lang/rust-clippy/pull/8876)
+* [`significant_drop_in_scrutinee`]: Improve lint message for types that are not
+  references and not trivially clone-able
+  [#8902](https://github.com/rust-lang/rust-clippy/pull/8902)
+* [`for_loops_over_fallibles`]: Now suggests the correct variant of `iter()`,
+  `iter_mut()` or `into_iter()`
+  [#8941](https://github.com/rust-lang/rust-clippy/pull/8941)
+
+### ICE Fixes
+
+* Fix ICE in [`let_unit_value`] when calling a `static`/`const` callable type
+  [#8835](https://github.com/rust-lang/rust-clippy/pull/8835)
+* Fix ICEs on callable `static`/`const`s
+  [#8896](https://github.com/rust-lang/rust-clippy/pull/8896)
+* [`needless_late_init`]
+  [#8912](https://github.com/rust-lang/rust-clippy/pull/8912)
+* Fix ICE in shadow lints
+  [#8913](https://github.com/rust-lang/rust-clippy/pull/8913)
+
+### Documentation Improvements
+
+* Clippy has a [Book](https://doc.rust-lang.org/nightly/clippy/) now!
+  [#7359](https://github.com/rust-lang/rust-clippy/pull/7359)
+* Add a *copy lint name*-button to Clippy's lint list
+  [#8839](https://github.com/rust-lang/rust-clippy/pull/8839)
+* Display past names of renamed lints on Clippy's lint list
+  [#8843](https://github.com/rust-lang/rust-clippy/pull/8843)
+* Add the ability to show the lint output in the lint list
+  [#8947](https://github.com/rust-lang/rust-clippy/pull/8947)
 
 ## Rust 1.62
 
-Current stable, released 2022-06-30
+Released 2022-06-30
 
 [d0cf3481...7c21f91b](https://github.com/rust-lang/rust-clippy/compare/d0cf3481...7c21f91b)
 
@@ -3481,6 +3627,7 @@ Released 2018-09-13
 [`cast_ref_to_mut`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_ref_to_mut
 [`cast_sign_loss`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_sign_loss
 [`cast_slice_different_sizes`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_slice_different_sizes
+[`cast_slice_from_raw_parts`]: https://rust-lang.github.io/rust-clippy/master/index.html#cast_slice_from_raw_parts
 [`char_lit_as_u8`]: https://rust-lang.github.io/rust-clippy/master/index.html#char_lit_as_u8
 [`chars_last_cmp`]: https://rust-lang.github.io/rust-clippy/master/index.html#chars_last_cmp
 [`chars_next_cmp`]: https://rust-lang.github.io/rust-clippy/master/index.html#chars_next_cmp
@@ -3496,6 +3643,7 @@ Released 2018-09-13
 [`collapsible_else_if`]: https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_else_if
 [`collapsible_if`]: https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_if
 [`collapsible_match`]: https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_match
+[`collapsible_str_replace`]: https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_str_replace
 [`comparison_chain`]: https://rust-lang.github.io/rust-clippy/master/index.html#comparison_chain
 [`comparison_to_empty`]: https://rust-lang.github.io/rust-clippy/master/index.html#comparison_to_empty
 [`const_static_lifetime`]: https://rust-lang.github.io/rust-clippy/master/index.html#const_static_lifetime
@@ -3656,6 +3804,8 @@ Released 2018-09-13
 [`iter_not_returning_iterator`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_not_returning_iterator
 [`iter_nth`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_nth
 [`iter_nth_zero`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_nth_zero
+[`iter_on_empty_collections`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_on_empty_collections
+[`iter_on_single_items`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_on_single_items
 [`iter_overeager_cloned`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_overeager_cloned
 [`iter_skip_next`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_skip_next
 [`iter_with_drain`]: https://rust-lang.github.io/rust-clippy/master/index.html#iter_with_drain
@@ -3697,6 +3847,7 @@ Released 2018-09-13
 [`manual_saturating_arithmetic`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_saturating_arithmetic
 [`manual_split_once`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_split_once
 [`manual_str_repeat`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_str_repeat
+[`manual_string_new`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_string_new
 [`manual_strip`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_strip
 [`manual_swap`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_swap
 [`manual_unwrap_or`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_unwrap_or
@@ -3747,6 +3898,7 @@ Released 2018-09-13
 [`module_name_repetitions`]: https://rust-lang.github.io/rust-clippy/master/index.html#module_name_repetitions
 [`modulo_arithmetic`]: https://rust-lang.github.io/rust-clippy/master/index.html#modulo_arithmetic
 [`modulo_one`]: https://rust-lang.github.io/rust-clippy/master/index.html#modulo_one
+[`multi_assignments`]: https://rust-lang.github.io/rust-clippy/master/index.html#multi_assignments
 [`multiple_crate_versions`]: https://rust-lang.github.io/rust-clippy/master/index.html#multiple_crate_versions
 [`multiple_inherent_impl`]: https://rust-lang.github.io/rust-clippy/master/index.html#multiple_inherent_impl
 [`must_use_candidate`]: https://rust-lang.github.io/rust-clippy/master/index.html#must_use_candidate
@@ -3827,6 +3979,7 @@ Released 2018-09-13
 [`partialeq_to_none`]: https://rust-lang.github.io/rust-clippy/master/index.html#partialeq_to_none
 [`path_buf_push_overwrite`]: https://rust-lang.github.io/rust-clippy/master/index.html#path_buf_push_overwrite
 [`pattern_type_mismatch`]: https://rust-lang.github.io/rust-clippy/master/index.html#pattern_type_mismatch
+[`positional_named_format_parameters`]: https://rust-lang.github.io/rust-clippy/master/index.html#positional_named_format_parameters
 [`possible_missing_comma`]: https://rust-lang.github.io/rust-clippy/master/index.html#possible_missing_comma
 [`precedence`]: https://rust-lang.github.io/rust-clippy/master/index.html#precedence
 [`print_in_format_impl`]: https://rust-lang.github.io/rust-clippy/master/index.html#print_in_format_impl
@@ -3872,6 +4025,7 @@ Released 2018-09-13
 [`replace_consts`]: https://rust-lang.github.io/rust-clippy/master/index.html#replace_consts
 [`rest_pat_in_fully_bound_structs`]: https://rust-lang.github.io/rust-clippy/master/index.html#rest_pat_in_fully_bound_structs
 [`result_expect_used`]: https://rust-lang.github.io/rust-clippy/master/index.html#result_expect_used
+[`result_large_err`]: https://rust-lang.github.io/rust-clippy/master/index.html#result_large_err
 [`result_map_or_into_option`]: https://rust-lang.github.io/rust-clippy/master/index.html#result_map_or_into_option
 [`result_map_unit_fn`]: https://rust-lang.github.io/rust-clippy/master/index.html#result_map_unit_fn
 [`result_map_unwrap_or_else`]: https://rust-lang.github.io/rust-clippy/master/index.html#result_map_unwrap_or_else
@@ -3930,6 +4084,7 @@ Released 2018-09-13
 [`suspicious_op_assign_impl`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_op_assign_impl
 [`suspicious_operation_groupings`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_operation_groupings
 [`suspicious_splitn`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_splitn
+[`suspicious_to_owned`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_to_owned
 [`suspicious_unary_op_formatting`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_unary_op_formatting
 [`swap_ptr_to_ref`]: https://rust-lang.github.io/rust-clippy/master/index.html#swap_ptr_to_ref
 [`tabs_in_doc_comments`]: https://rust-lang.github.io/rust-clippy/master/index.html#tabs_in_doc_comments
@@ -4002,6 +4157,7 @@ Released 2018-09-13
 [`unused_collect`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_collect
 [`unused_io_amount`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_io_amount
 [`unused_label`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_label
+[`unused_peekable`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_peekable
 [`unused_rounding`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_rounding
 [`unused_self`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_self
 [`unused_unit`]: https://rust-lang.github.io/rust-clippy/master/index.html#unused_unit

src/tools/clippy/clippy_dev/src/bless.rs

@@ -37,7 +37,7 @@ fn update_reference_file(test_output_entry: &DirEntry, ignore_timestamp: bool) {
         return;
     }
 
-    let test_output_file = fs::read(&test_output_path).expect("Unable to read test output file");
+    let test_output_file = fs::read(test_output_path).expect("Unable to read test output file");
     let reference_file = fs::read(&reference_file_path).unwrap_or_default();
 
     if test_output_file != reference_file {

src/tools/clippy/clippy_dev/src/fmt.rs

@@ -46,7 +46,7 @@ pub fn run(check: bool, verbose: bool) {
         // dependency
         if fs::read_to_string(project_root.join("Cargo.toml"))
             .expect("Failed to read clippy Cargo.toml")
-            .contains(&"[target.'cfg(NOT_A_PLATFORM)'.dependencies]")
+            .contains("[target.'cfg(NOT_A_PLATFORM)'.dependencies]")
         {
             return Err(CliError::IntellijSetupActive);
         }
@@ -193,10 +193,10 @@ fn rustfmt_test(context: &FmtContext) -> Result<(), CliError> {
     let args = &["--version"];
 
     if context.verbose {
-        println!("{}", format_command(&program, &dir, args));
+        println!("{}", format_command(program, &dir, args));
     }
 
-    let output = Command::new(&program).current_dir(&dir).args(args.iter()).output()?;
+    let output = Command::new(program).current_dir(&dir).args(args.iter()).output()?;
 
     if output.status.success() {
         Ok(())
@@ -207,7 +207,7 @@ fn rustfmt_test(context: &FmtContext) -> Result<(), CliError> {
         Err(CliError::RustfmtNotInstalled)
     } else {
         Err(CliError::CommandFailed(
-            format_command(&program, &dir, args),
+            format_command(program, &dir, args),
             std::str::from_utf8(&output.stderr).unwrap_or("").to_string(),
         ))
     }

src/tools/clippy/clippy_dev/src/new_lint.rs

@@ -155,7 +155,7 @@ fn to_camel_case(name: &str) -> String {
     name.split('_')
         .map(|s| {
             if s.is_empty() {
-                String::from("")
+                String::new()
             } else {
                 [&s[0..1].to_uppercase(), &s[1..]].concat()
             }

src/tools/clippy/clippy_dev/src/update_lints.rs

@@ -418,7 +418,7 @@ fn remove_lint_declaration(name: &str, path: &Path, lints: &mut Vec<Lint>) -> io
             .expect("failed to find `impl_lint_pass` terminator");
 
         impl_lint_pass_end += impl_lint_pass_start;
-        if let Some(lint_name_pos) = content[impl_lint_pass_start..impl_lint_pass_end].find(&lint_name_upper) {
+        if let Some(lint_name_pos) = content[impl_lint_pass_start..impl_lint_pass_end].find(lint_name_upper) {
             let mut lint_name_end = impl_lint_pass_start + (lint_name_pos + lint_name_upper.len());
             for c in content[lint_name_end..impl_lint_pass_end].chars() {
                 // Remove trailing whitespace
@@ -451,7 +451,7 @@ fn remove_lint_declaration(name: &str, path: &Path, lints: &mut Vec<Lint>) -> io
                 }
 
                 let mut content =
-                    fs::read_to_string(&path).unwrap_or_else(|_| panic!("failed to read `{}`", path.to_string_lossy()));
+                    fs::read_to_string(path).unwrap_or_else(|_| panic!("failed to read `{}`", path.to_string_lossy()));
 
                 eprintln!(
                     "warn: you will have to manually remove any code related to `{}` from `{}`",

src/tools/clippy/clippy_lints/src/as_underscore.rs

@@ -1,74 +0,0 @@
-use clippy_utils::diagnostics::{span_lint_and_help, span_lint_and_then};
-use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind, TyKind};
-use rustc_lint::{LateContext, LateLintPass, LintContext};
-use rustc_middle::lint::in_external_macro;
-use rustc_middle::ty;
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Check for the usage of `as _` conversion using inferred type.
-    ///
-    /// ### Why is this bad?
-    /// The conversion might include lossy conversion and dangerous cast that might go
-    /// undetected du to the type being inferred.
-    ///
-    /// The lint is allowed by default as using `_` is less wordy than always specifying the type.
-    ///
-    /// ### Example
-    /// ```rust
-    /// fn foo(n: usize) {}
-    /// let n: u16 = 256;
-    /// foo(n as _);
-    /// ```
-    /// Use instead:
-    /// ```rust
-    /// fn foo(n: usize) {}
-    /// let n: u16 = 256;
-    /// foo(n as usize);
-    /// ```
-    #[clippy::version = "1.63.0"]
-    pub AS_UNDERSCORE,
-    restriction,
-    "detects `as _` conversion"
-}
-declare_lint_pass!(AsUnderscore => [AS_UNDERSCORE]);
-
-impl<'tcx> LateLintPass<'tcx> for AsUnderscore {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &Expr<'tcx>) {
-        if in_external_macro(cx.sess(), expr.span) {
-            return;
-        }
-
-        if let ExprKind::Cast(_, ty) = expr.kind && let TyKind::Infer = ty.kind {
-
-            let ty_resolved = cx.typeck_results().expr_ty(expr);
-            if let ty::Error(_) = ty_resolved.kind() {
-                span_lint_and_help(
-                    cx,
-                AS_UNDERSCORE,
-                expr.span,
-                "using `as _` conversion",
-                None,
-                "consider giving the type explicitly",
-                );
-            } else {
-            span_lint_and_then(
-                cx,
-                AS_UNDERSCORE,
-                expr.span,
-                "using `as _` conversion",
-                |diag| {
-                    diag.span_suggestion(
-                        ty.span,
-                        "consider giving the type explicitly",
-                        ty_resolved,
-                        Applicability::MachineApplicable,
-                    );
-            }
-            );
-        }
-        }
-    }
-}

src/tools/clippy/clippy_lints/src/borrow_as_ptr.rs

@@ -1,99 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::is_no_std_crate;
-use clippy_utils::source::snippet_opt;
-use clippy_utils::{meets_msrv, msrvs};
-use if_chain::if_chain;
-use rustc_errors::Applicability;
-use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability, TyKind};
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_semver::RustcVersion;
-use rustc_session::{declare_tool_lint, impl_lint_pass};
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for the usage of `&expr as *const T` or
-    /// `&mut expr as *mut T`, and suggest using `ptr::addr_of` or
-    /// `ptr::addr_of_mut` instead.
-    ///
-    /// ### Why is this bad?
-    /// This would improve readability and avoid creating a reference
-    /// that points to an uninitialized value or unaligned place.
-    /// Read the `ptr::addr_of` docs for more information.
-    ///
-    /// ### Example
-    /// ```rust
-    /// let val = 1;
-    /// let p = &val as *const i32;
-    ///
-    /// let mut val_mut = 1;
-    /// let p_mut = &mut val_mut as *mut i32;
-    /// ```
-    /// Use instead:
-    /// ```rust
-    /// let val = 1;
-    /// let p = std::ptr::addr_of!(val);
-    ///
-    /// let mut val_mut = 1;
-    /// let p_mut = std::ptr::addr_of_mut!(val_mut);
-    /// ```
-    #[clippy::version = "1.60.0"]
-    pub BORROW_AS_PTR,
-    pedantic,
-    "borrowing just to cast to a raw pointer"
-}
-
-impl_lint_pass!(BorrowAsPtr => [BORROW_AS_PTR]);
-
-pub struct BorrowAsPtr {
-    msrv: Option<RustcVersion>,
-}
-
-impl BorrowAsPtr {
-    #[must_use]
-    pub fn new(msrv: Option<RustcVersion>) -> Self {
-        Self { msrv }
-    }
-}
-
-impl<'tcx> LateLintPass<'tcx> for BorrowAsPtr {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
-        if !meets_msrv(self.msrv, msrvs::BORROW_AS_PTR) {
-            return;
-        }
-
-        if expr.span.from_expansion() {
-            return;
-        }
-
-        if_chain! {
-            if let ExprKind::Cast(left_expr, ty) = &expr.kind;
-            if let TyKind::Ptr(_) = ty.kind;
-            if let ExprKind::AddrOf(BorrowKind::Ref, mutability, e) = &left_expr.kind;
-
-            then {
-                let core_or_std = if is_no_std_crate(cx) { "core" } else { "std" };
-                let macro_name = match mutability {
-                    Mutability::Not => "addr_of",
-                    Mutability::Mut => "addr_of_mut",
-                };
-
-                span_lint_and_sugg(
-                    cx,
-                    BORROW_AS_PTR,
-                    expr.span,
-                    "borrow as raw pointer",
-                    "try",
-                    format!(
-                        "{}::ptr::{}!({})",
-                        core_or_std,
-                        macro_name,
-                        snippet_opt(cx, e.span).unwrap()
-                    ),
-                    Applicability::MachineApplicable,
-                );
-            }
-        }
-    }
-
-    extract_msrv_attr!(LateContext);
-}

src/tools/clippy/clippy_lints/src/borrow_deref_ref.rs

@@ -29,22 +29,17 @@ declare_clippy_lint! {
     ///
     /// ### Example
     /// ```rust
-    /// fn foo(_x: &str) {}
-    ///
     /// let s = &String::new();
     ///
     /// let a: &String = &* s;
-    /// foo(&*s);
     /// ```
     ///
     /// Use instead:
     /// ```rust
-    /// # fn foo(_x: &str) {}
     /// # let s = &String::new();
     /// let a: &String = s;
-    /// foo(&**s);
     /// ```
-    #[clippy::version = "1.59.0"]
+    #[clippy::version = "1.63.0"]
     pub BORROW_DEREF_REF,
     complexity,
     "deref on an immutable reference returns the same type as itself"

src/tools/clippy/clippy_lints/src/bytecount.rs

@@ -1,103 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet_with_applicability;
-use clippy_utils::ty::match_type;
-use clippy_utils::visitors::is_local_used;
-use clippy_utils::{path_to_local_id, paths, peel_blocks, peel_ref_operators, strip_pat_refs};
-use if_chain::if_chain;
-use rustc_errors::Applicability;
-use rustc_hir::{BinOpKind, Closure, Expr, ExprKind, PatKind};
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::ty::{self, UintTy};
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::sym;
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for naive byte counts
-    ///
-    /// ### Why is this bad?
-    /// The [`bytecount`](https://crates.io/crates/bytecount)
-    /// crate has methods to count your bytes faster, especially for large slices.
-    ///
-    /// ### Known problems
-    /// If you have predominantly small slices, the
-    /// `bytecount::count(..)` method may actually be slower. However, if you can
-    /// ensure that less than 2³²-1 matches arise, the `naive_count_32(..)` can be
-    /// faster in those cases.
-    ///
-    /// ### Example
-    /// ```rust
-    /// # let vec = vec![1_u8];
-    /// let count = vec.iter().filter(|x| **x == 0u8).count();
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust,ignore
-    /// # let vec = vec![1_u8];
-    /// let count = bytecount::count(&vec, 0u8);
-    /// ```
-    #[clippy::version = "pre 1.29.0"]
-    pub NAIVE_BYTECOUNT,
-    pedantic,
-    "use of naive `<slice>.filter(|&x| x == y).count()` to count byte values"
-}
-
-declare_lint_pass!(ByteCount => [NAIVE_BYTECOUNT]);
-
-impl<'tcx> LateLintPass<'tcx> for ByteCount {
-    fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
-        if_chain! {
-            if let ExprKind::MethodCall(count, [count_recv], _) = expr.kind;
-            if count.ident.name == sym::count;
-            if let ExprKind::MethodCall(filter, [filter_recv, filter_arg], _) = count_recv.kind;
-            if filter.ident.name == sym!(filter);
-            if let ExprKind::Closure(&Closure { body, .. }) = filter_arg.kind;
-            let body = cx.tcx.hir().body(body);
-            if let [param] = body.params;
-            if let PatKind::Binding(_, arg_id, _, _) = strip_pat_refs(param.pat).kind;
-            if let ExprKind::Binary(ref op, l, r) = body.value.kind;
-            if op.node == BinOpKind::Eq;
-            if match_type(cx,
-                       cx.typeck_results().expr_ty(filter_recv).peel_refs(),
-                       &paths::SLICE_ITER);
-            let operand_is_arg = |expr| {
-                let expr = peel_ref_operators(cx, peel_blocks(expr));
-                path_to_local_id(expr, arg_id)
-            };
-            let needle = if operand_is_arg(l) {
-                r
-            } else if operand_is_arg(r) {
-                l
-            } else {
-                return;
-            };
-            if ty::Uint(UintTy::U8) == *cx.typeck_results().expr_ty(needle).peel_refs().kind();
-            if !is_local_used(cx, needle, arg_id);
-            then {
-                let haystack = if let ExprKind::MethodCall(path, args, _) =
-                        filter_recv.kind {
-                    let p = path.ident.name;
-                    if (p == sym::iter || p == sym!(iter_mut)) && args.len() == 1 {
-                        &args[0]
-                    } else {
-                        filter_recv
-                    }
-                } else {
-                    filter_recv
-                };
-                let mut applicability = Applicability::MaybeIncorrect;
-                span_lint_and_sugg(
-                    cx,
-                    NAIVE_BYTECOUNT,
-                    expr.span,
-                    "you appear to be counting bytes the naive way",
-                    "consider using the bytecount crate",
-                    format!("bytecount::count({}, {})",
-                            snippet_with_applicability(cx, haystack.span, "..", &mut applicability),
-                            snippet_with_applicability(cx, needle.span, "..", &mut applicability)),
-                    applicability,
-                );
-            }
-        };
-    }
-}

src/tools/clippy/clippy_lints/src/bytes_count_to_len.rs

@@ -1,70 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet_with_applicability;
-use clippy_utils::ty::is_type_diagnostic_item;
-use clippy_utils::{match_def_path, paths};
-use if_chain::if_chain;
-use rustc_errors::Applicability;
-use rustc_hir as hir;
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::ty;
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::sym;
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// It checks for `str::bytes().count()` and suggests replacing it with
-    /// `str::len()`.
-    ///
-    /// ### Why is this bad?
-    /// `str::bytes().count()` is longer and may not be as performant as using
-    /// `str::len()`.
-    ///
-    /// ### Example
-    /// ```rust
-    /// "hello".bytes().count();
-    /// String::from("hello").bytes().count();
-    /// ```
-    /// Use instead:
-    /// ```rust
-    /// "hello".len();
-    /// String::from("hello").len();
-    /// ```
-    #[clippy::version = "1.62.0"]
-    pub BYTES_COUNT_TO_LEN,
-    complexity,
-    "Using `bytes().count()` when `len()` performs the same functionality"
-}
-
-declare_lint_pass!(BytesCountToLen => [BYTES_COUNT_TO_LEN]);
-
-impl<'tcx> LateLintPass<'tcx> for BytesCountToLen {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
-        if_chain! {
-            if let hir::ExprKind::MethodCall(_, expr_args, _) = &expr.kind;
-            if let Some(expr_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
-            if match_def_path(cx, expr_def_id, &paths::ITER_COUNT);
-
-            if let [bytes_expr] = &**expr_args;
-            if let hir::ExprKind::MethodCall(_, bytes_args, _) = &bytes_expr.kind;
-            if let Some(bytes_def_id) = cx.typeck_results().type_dependent_def_id(bytes_expr.hir_id);
-            if match_def_path(cx, bytes_def_id, &paths::STR_BYTES);
-
-            if let [str_expr] = &**bytes_args;
-            let ty = cx.typeck_results().expr_ty(str_expr).peel_refs();
-
-            if is_type_diagnostic_item(cx, ty, sym::String) || ty.kind() == &ty::Str;
-            then {
-                let mut applicability = Applicability::MachineApplicable;
-                span_lint_and_sugg(
-                    cx,
-                    BYTES_COUNT_TO_LEN,
-                    expr.span,
-                    "using long and hard to read `.bytes().count()`",
-                    "consider calling `.len()` instead",
-                    format!("{}.len()", snippet_with_applicability(cx, str_expr.span, "..", &mut applicability)),
-                    applicability
-                );
-            }
-        };
-    }
-}

src/tools/clippy/clippy_lints/src/case_sensitive_file_extension_comparisons.rs

@@ -1,86 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_help;
-use if_chain::if_chain;
-use rustc_ast::ast::LitKind;
-use rustc_hir::{Expr, ExprKind, PathSegment};
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::ty;
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::{source_map::Spanned, symbol::sym, Span};
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for calls to `ends_with` with possible file extensions
-    /// and suggests to use a case-insensitive approach instead.
-    ///
-    /// ### Why is this bad?
-    /// `ends_with` is case-sensitive and may not detect files with a valid extension.
-    ///
-    /// ### Example
-    /// ```rust
-    /// fn is_rust_file(filename: &str) -> bool {
-    ///     filename.ends_with(".rs")
-    /// }
-    /// ```
-    /// Use instead:
-    /// ```rust
-    /// fn is_rust_file(filename: &str) -> bool {
-    ///     let filename = std::path::Path::new(filename);
-    ///     filename.extension()
-    ///         .map(|ext| ext.eq_ignore_ascii_case("rs"))
-    ///         .unwrap_or(false)
-    /// }
-    /// ```
-    #[clippy::version = "1.51.0"]
-    pub CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS,
-    pedantic,
-    "Checks for calls to ends_with with case-sensitive file extensions"
-}
-
-declare_lint_pass!(CaseSensitiveFileExtensionComparisons => [CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS]);
-
-fn check_case_sensitive_file_extension_comparison(ctx: &LateContext<'_>, expr: &Expr<'_>) -> Option<Span> {
-    if_chain! {
-        if let ExprKind::MethodCall(PathSegment { ident, .. }, [obj, extension, ..], span) = expr.kind;
-        if ident.as_str() == "ends_with";
-        if let ExprKind::Lit(Spanned { node: LitKind::Str(ext_literal, ..), ..}) = extension.kind;
-        if (2..=6).contains(&ext_literal.as_str().len());
-        if ext_literal.as_str().starts_with('.');
-        if ext_literal.as_str().chars().skip(1).all(|c| c.is_uppercase() || c.is_ascii_digit())
-            || ext_literal.as_str().chars().skip(1).all(|c| c.is_lowercase() || c.is_ascii_digit());
-        then {
-            let mut ty = ctx.typeck_results().expr_ty(obj);
-            ty = match ty.kind() {
-                ty::Ref(_, ty, ..) => *ty,
-                _ => ty
-            };
-
-            match ty.kind() {
-                ty::Str => {
-                    return Some(span);
-                },
-                ty::Adt(def, _) => {
-                    if ctx.tcx.is_diagnostic_item(sym::String, def.did()) {
-                        return Some(span);
-                    }
-                },
-                _ => { return None; }
-            }
-        }
-    }
-    None
-}
-
-impl<'tcx> LateLintPass<'tcx> for CaseSensitiveFileExtensionComparisons {
-    fn check_expr(&mut self, ctx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
-        if let Some(span) = check_case_sensitive_file_extension_comparison(ctx, expr) {
-            span_lint_and_help(
-                ctx,
-                CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS,
-                span,
-                "case-sensitive file extension comparison",
-                None,
-                "consider using a case-insensitive comparison instead",
-            );
-        }
-    }
-}

src/tools/clippy/clippy_lints/src/casts/as_underscore.rs

@@ -0,0 +1,25 @@
+use clippy_utils::diagnostics::span_lint_and_then;
+use rustc_errors::Applicability;
+use rustc_hir::{Expr, Ty, TyKind};
+use rustc_lint::LateContext;
+use rustc_middle::ty;
+
+use super::AS_UNDERSCORE;
+
+pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, ty: &'tcx Ty<'_>) {
+    if matches!(ty.kind, TyKind::Infer) {
+        span_lint_and_then(cx, AS_UNDERSCORE, expr.span, "using `as _` conversion", |diag| {
+            let ty_resolved = cx.typeck_results().expr_ty(expr);
+            if let ty::Error(_) = ty_resolved.kind() {
+                diag.help("consider giving the type explicitly");
+            } else {
+                diag.span_suggestion(
+                    ty.span,
+                    "consider giving the type explicitly",
+                    ty_resolved,
+                    Applicability::MachineApplicable,
+                );
+            }
+        });
+    }
+}

src/tools/clippy/clippy_lints/src/casts/borrow_as_ptr.rs

@@ -0,0 +1,37 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::is_no_std_crate;
+use clippy_utils::source::snippet_with_context;
+use rustc_errors::Applicability;
+use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability, Ty, TyKind};
+use rustc_lint::LateContext;
+
+use super::BORROW_AS_PTR;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'_>,
+    cast_expr: &'tcx Expr<'_>,
+    cast_to: &'tcx Ty<'_>,
+) {
+    if matches!(cast_to.kind, TyKind::Ptr(_))
+        && let ExprKind::AddrOf(BorrowKind::Ref, mutability, e) = cast_expr.kind
+    {
+        let core_or_std = if is_no_std_crate(cx) { "core" } else { "std" };
+        let macro_name = match mutability {
+            Mutability::Not => "addr_of",
+            Mutability::Mut => "addr_of_mut",
+        };
+        let mut app = Applicability::MachineApplicable;
+        let snip = snippet_with_context(cx, e.span, cast_expr.span.ctxt(), "..", &mut app).0;
+
+        span_lint_and_sugg(
+            cx,
+            BORROW_AS_PTR,
+            expr.span,
+            "borrow as raw pointer",
+            "try",
+            format!("{}::ptr::{}!({})", core_or_std, macro_name, snip),
+            Applicability::MachineApplicable,
+        );
+    }
+}

src/tools/clippy/clippy_lints/src/casts/cast_slice_from_raw_parts.rs

@@ -0,0 +1,63 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_with_applicability;
+use clippy_utils::{match_def_path, meets_msrv, msrvs, paths};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir::{def_id::DefId, Expr, ExprKind};
+use rustc_lint::LateContext;
+use rustc_middle::ty::{self, Ty};
+use rustc_semver::RustcVersion;
+
+use super::CAST_SLICE_FROM_RAW_PARTS;
+
+enum RawPartsKind {
+    Immutable,
+    Mutable,
+}
+
+fn raw_parts_kind(cx: &LateContext<'_>, did: DefId) -> Option<RawPartsKind> {
+    if match_def_path(cx, did, &paths::SLICE_FROM_RAW_PARTS) {
+        Some(RawPartsKind::Immutable)
+    } else if match_def_path(cx, did, &paths::SLICE_FROM_RAW_PARTS_MUT) {
+        Some(RawPartsKind::Mutable)
+    } else {
+        None
+    }
+}
+
+pub(super) fn check(
+    cx: &LateContext<'_>,
+    expr: &Expr<'_>,
+    cast_expr: &Expr<'_>,
+    cast_to: Ty<'_>,
+    msrv: Option<RustcVersion>,
+) {
+    if_chain! {
+        if meets_msrv(msrv, msrvs::PTR_SLICE_RAW_PARTS);
+        if let ty::RawPtr(ptrty) = cast_to.kind();
+        if let ty::Slice(_) = ptrty.ty.kind();
+        if let ExprKind::Call(fun, [ptr_arg, len_arg]) = cast_expr.peel_blocks().kind;
+        if let ExprKind::Path(ref qpath) = fun.kind;
+        if let Some(fun_def_id) = cx.qpath_res(qpath, fun.hir_id).opt_def_id();
+        if let Some(rpk) = raw_parts_kind(cx, fun_def_id);
+        then {
+            let func = match rpk {
+                RawPartsKind::Immutable => "from_raw_parts",
+                RawPartsKind::Mutable => "from_raw_parts_mut"
+            };
+            let span = expr.span;
+            let mut applicability = Applicability::MachineApplicable;
+            let ptr = snippet_with_applicability(cx, ptr_arg.span, "ptr", &mut applicability);
+            let len = snippet_with_applicability(cx, len_arg.span, "len", &mut applicability);
+            span_lint_and_sugg(
+                cx,
+                CAST_SLICE_FROM_RAW_PARTS,
+                span,
+                &format!("casting the result of `{func}` to {cast_to}"),
+                "replace with",
+                format!("core::ptr::slice_{func}({ptr}, {len})"),
+                applicability
+            );
+        }
+    }
+}

src/tools/clippy/clippy_lints/src/casts/mod.rs

@@ -1,3 +1,5 @@
+mod as_underscore;
+mod borrow_as_ptr;
 mod cast_abs_to_unsigned;
 mod cast_enum_constructor;
 mod cast_lossless;
@@ -8,6 +10,7 @@ mod cast_ptr_alignment;
 mod cast_ref_to_mut;
 mod cast_sign_loss;
 mod cast_slice_different_sizes;
+mod cast_slice_from_raw_parts;
 mod char_lit_as_u8;
 mod fn_to_numeric_cast;
 mod fn_to_numeric_cast_any;
@@ -16,7 +19,7 @@ mod ptr_as_ptr;
 mod unnecessary_cast;
 mod utils;
 
-use clippy_utils::is_hir_ty_cfg_dependant;
+use clippy_utils::{is_hir_ty_cfg_dependant, meets_msrv, msrvs};
 use rustc_hir::{Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::lint::in_external_macro;
@@ -506,6 +509,93 @@ declare_clippy_lint! {
     "casting the result of `abs()` to an unsigned integer can panic"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// Check for the usage of `as _` conversion using inferred type.
+    ///
+    /// ### Why is this bad?
+    /// The conversion might include lossy conversion and dangerous cast that might go
+    /// undetected due to the type being inferred.
+    ///
+    /// The lint is allowed by default as using `_` is less wordy than always specifying the type.
+    ///
+    /// ### Example
+    /// ```rust
+    /// fn foo(n: usize) {}
+    /// let n: u16 = 256;
+    /// foo(n as _);
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// fn foo(n: usize) {}
+    /// let n: u16 = 256;
+    /// foo(n as usize);
+    /// ```
+    #[clippy::version = "1.63.0"]
+    pub AS_UNDERSCORE,
+    restriction,
+    "detects `as _` conversion"
+}
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for the usage of `&expr as *const T` or
+    /// `&mut expr as *mut T`, and suggest using `ptr::addr_of` or
+    /// `ptr::addr_of_mut` instead.
+    ///
+    /// ### Why is this bad?
+    /// This would improve readability and avoid creating a reference
+    /// that points to an uninitialized value or unaligned place.
+    /// Read the `ptr::addr_of` docs for more information.
+    ///
+    /// ### Example
+    /// ```rust
+    /// let val = 1;
+    /// let p = &val as *const i32;
+    ///
+    /// let mut val_mut = 1;
+    /// let p_mut = &mut val_mut as *mut i32;
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// let val = 1;
+    /// let p = std::ptr::addr_of!(val);
+    ///
+    /// let mut val_mut = 1;
+    /// let p_mut = std::ptr::addr_of_mut!(val_mut);
+    /// ```
+    #[clippy::version = "1.60.0"]
+    pub BORROW_AS_PTR,
+    pedantic,
+    "borrowing just to cast to a raw pointer"
+}
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for a raw slice being cast to a slice pointer
+    ///
+    /// ### Why is this bad?
+    /// This can result in multiple `&mut` references to the same location when only a pointer is
+    /// required.
+    /// `ptr::slice_from_raw_parts` is a safe alternative that doesn't require
+    /// the same [safety requirements] to be upheld.
+    ///
+    /// ### Example
+    /// ```rust,ignore
+    /// let _: *const [u8] = std::slice::from_raw_parts(ptr, len) as *const _;
+    /// let _: *mut [u8] = std::slice::from_raw_parts_mut(ptr, len) as *mut _;
+    /// ```
+    /// Use instead:
+    /// ```rust,ignore
+    /// let _: *const [u8] = std::ptr::slice_from_raw_parts(ptr, len);
+    /// let _: *mut [u8] = std::ptr::slice_from_raw_parts_mut(ptr, len);
+    /// ```
+    /// [safety requirements]: https://doc.rust-lang.org/std/slice/fn.from_raw_parts.html#safety
+    #[clippy::version = "1.64.0"]
+    pub CAST_SLICE_FROM_RAW_PARTS,
+    suspicious,
+    "casting a slice created from a pointer and length to a slice pointer"
+}
+
 pub struct Casts {
     msrv: Option<RustcVersion>,
 }
@@ -534,7 +624,10 @@ impl_lint_pass!(Casts => [
     PTR_AS_PTR,
     CAST_ENUM_TRUNCATION,
     CAST_ENUM_CONSTRUCTOR,
-    CAST_ABS_TO_UNSIGNED
+    CAST_ABS_TO_UNSIGNED,
+    AS_UNDERSCORE,
+    BORROW_AS_PTR,
+    CAST_SLICE_FROM_RAW_PARTS
 ]);
 
 impl<'tcx> LateLintPass<'tcx> for Casts {
@@ -547,8 +640,8 @@ impl<'tcx> LateLintPass<'tcx> for Casts {
             return;
         }
 
-        if let ExprKind::Cast(cast_expr, cast_to) = expr.kind {
+        if let ExprKind::Cast(cast_expr, cast_to_hir) = expr.kind {
-            if is_hir_ty_cfg_dependant(cx, cast_to) {
+            if is_hir_ty_cfg_dependant(cx, cast_to_hir) {
                 return;
             }
             let (cast_from, cast_to) = (
@@ -559,7 +652,7 @@ impl<'tcx> LateLintPass<'tcx> for Casts {
             if unnecessary_cast::check(cx, expr, cast_expr, cast_from, cast_to) {
                 return;
             }
-
+            cast_slice_from_raw_parts::check(cx, expr, cast_expr, cast_to, self.msrv);
             fn_to_numeric_cast_any::check(cx, expr, cast_expr, cast_from, cast_to);
             fn_to_numeric_cast::check(cx, expr, cast_expr, cast_from, cast_to);
             fn_to_numeric_cast_with_truncation::check(cx, expr, cast_expr, cast_from, cast_to);
@@ -575,6 +668,12 @@ impl<'tcx> LateLintPass<'tcx> for Casts {
                 cast_lossless::check(cx, expr, cast_expr, cast_from, cast_to, self.msrv);
                 cast_enum_constructor::check(cx, expr, cast_expr, cast_from);
             }
+
+            as_underscore::check(cx, expr, cast_to_hir);
+
+            if meets_msrv(self.msrv, msrvs::BORROW_AS_PTR) {
+                borrow_as_ptr::check(cx, expr, cast_expr, cast_to_hir);
+            }
         }
 
         cast_ref_to_mut::check(cx, expr);

src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs

@@ -90,13 +90,20 @@ pub(super) fn check<'tcx>(
 
 fn lint_unnecessary_cast(cx: &LateContext<'_>, expr: &Expr<'_>, literal_str: &str, cast_from: Ty<'_>, cast_to: Ty<'_>) {
     let literal_kind_name = if cast_from.is_integral() { "integer" } else { "float" };
+    let replaced_literal;
+    let matchless = if literal_str.contains(['(', ')']) {
+        replaced_literal = literal_str.replace(['(', ')'], "");
+        &replaced_literal
+    } else {
+        literal_str
+    };
     span_lint_and_sugg(
         cx,
         UNNECESSARY_CAST,
         expr.span,
         &format!("casting {} literal to `{}` is unnecessary", literal_kind_name, cast_to),
         "try",
-        format!("{}_{}", literal_str.trim_end_matches('.'), cast_to),
+        format!("{}_{}", matchless.trim_end_matches('.'), cast_to),
         Applicability::MachineApplicable,
     );
 }

src/tools/clippy/clippy_lints/src/dereference.rs

@@ -1,24 +1,34 @@
 use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_hir_and_then};
 use clippy_utils::source::{snippet_with_applicability, snippet_with_context};
 use clippy_utils::sugg::has_enclosing_paren;
-use clippy_utils::ty::{expr_sig, peel_mid_ty_refs, ty_sig, variant_of_res};
+use clippy_utils::ty::{expr_sig, is_copy, peel_mid_ty_refs, ty_sig, variant_of_res};
-use clippy_utils::{get_parent_expr, get_parent_expr_for_hir, is_lint_allowed, path_to_local, walk_to_expr_usage};
+use clippy_utils::{
+    fn_def_id, get_parent_expr, get_parent_expr_for_hir, is_lint_allowed, meets_msrv, msrvs, path_to_local,
+    walk_to_expr_usage,
+};
 use rustc_ast::util::parser::{PREC_POSTFIX, PREC_PREFIX};
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_errors::Applicability;
 use rustc_hir::intravisit::{walk_ty, Visitor};
 use rustc_hir::{
-    self as hir, BindingAnnotation, Body, BodyId, BorrowKind, Closure, Expr, ExprKind, FnRetTy, GenericArg, HirId,
+    self as hir, def_id::DefId, BindingAnnotation, Body, BodyId, BorrowKind, Closure, Expr, ExprKind, FnRetTy,
-    ImplItem, ImplItemKind, Item, ItemKind, Local, MatchSource, Mutability, Node, Pat, PatKind, Path, QPath, TraitItem,
+    GenericArg, HirId, ImplItem, ImplItemKind, Item, ItemKind, Local, MatchSource, Mutability, Node, Pat, PatKind,
-    TraitItemKind, TyKind, UnOp,
+    Path, QPath, TraitItem, TraitItemKind, TyKind, UnOp,
 };
+use rustc_index::bit_set::BitSet;
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty::adjustment::{Adjust, Adjustment, AutoBorrow, AutoBorrowMutability};
-use rustc_middle::ty::{self, Binder, BoundVariableKind, List, Ty, TyCtxt, TypeVisitable, TypeckResults};
+use rustc_middle::ty::{
+    self, subst::Subst, Binder, BoundVariableKind, EarlyBinder, FnSig, GenericArgKind, List, ParamTy, PredicateKind,
+    ProjectionPredicate, Ty, TyCtxt, TypeVisitable, TypeckResults,
+};
+use rustc_semver::RustcVersion;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::{symbol::sym, Span, Symbol, DUMMY_SP};
-use rustc_trait_selection::infer::InferCtxtExt;
+use rustc_trait_selection::infer::InferCtxtExt as _;
+use rustc_trait_selection::traits::{query::evaluate_obligation::InferCtxtExt as _, Obligation, ObligationCause};
+use std::collections::VecDeque;
 
 declare_clippy_lint! {
     /// ### What it does
@@ -151,6 +161,7 @@ pub struct Dereferencing {
     /// been finished. Note we can't lint at the end of every body as they can be nested within each
     /// other.
     current_body: Option<BodyId>,
+
     /// The list of locals currently being checked by the lint.
     /// If the value is `None`, then the binding has been seen as a ref pattern, but is not linted.
     /// This is needed for or patterns where one of the branches can be linted, but another can not
@@ -158,6 +169,19 @@ pub struct Dereferencing {
     ///
     /// e.g. `m!(x) | Foo::Bar(ref x)`
     ref_locals: FxIndexMap<HirId, Option<RefPat>>,
+
+    // `IntoIterator` for arrays requires Rust 1.53.
+    msrv: Option<RustcVersion>,
+}
+
+impl Dereferencing {
+    #[must_use]
+    pub fn new(msrv: Option<RustcVersion>) -> Self {
+        Self {
+            msrv,
+            ..Dereferencing::default()
+        }
+    }
 }
 
 struct StateData {
@@ -170,6 +194,7 @@ struct StateData {
 struct DerefedBorrow {
     count: usize,
     msg: &'static str,
+    snip_expr: Option<HirId>,
 }
 
 enum State {
@@ -250,7 +275,7 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing {
         match (self.state.take(), kind) {
             (None, kind) => {
                 let expr_ty = typeck.expr_ty(expr);
-                let (position, adjustments) = walk_parents(cx, expr);
+                let (position, adjustments) = walk_parents(cx, expr, self.msrv);
 
                 match kind {
                     RefOp::Deref => {
@@ -331,20 +356,23 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing {
                         let deref_msg =
                             "this expression creates a reference which is immediately dereferenced by the compiler";
                         let borrow_msg = "this expression borrows a value the compiler would automatically borrow";
+                        let impl_msg = "the borrowed expression implements the required traits";
 
-                        let (required_refs, msg) = if position.can_auto_borrow() {
+                        let (required_refs, msg, snip_expr) = if position.can_auto_borrow() {
-                            (1, if deref_count == 1 { borrow_msg } else { deref_msg })
+                            (1, if deref_count == 1 { borrow_msg } else { deref_msg }, None)
+                        } else if let Position::ImplArg(hir_id) = position {
+                            (0, impl_msg, Some(hir_id))
                         } else if let Some(&Adjust::Borrow(AutoBorrow::Ref(_, mutability))) =
                             next_adjust.map(|a| &a.kind)
                         {
                             if matches!(mutability, AutoBorrowMutability::Mut { .. }) && !position.is_reborrow_stable()
                             {
-                                (3, deref_msg)
+                                (3, deref_msg, None)
                             } else {
-                                (2, deref_msg)
+                                (2, deref_msg, None)
                             }
                         } else {
-                            (2, deref_msg)
+                            (2, deref_msg, None)
                         };
 
                         if deref_count >= required_refs {
@@ -354,6 +382,7 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing {
                                     // can't be removed without breaking the code. See earlier comment.
                                     count: deref_count - required_refs,
                                     msg,
+                                    snip_expr,
                                 }),
                                 StateData { span: expr.span, hir_id: expr.hir_id, position },
                             ));
@@ -510,7 +539,7 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing {
                             spans: vec![pat.span],
                             app,
                             replacements: vec![(pat.span, snip.into())],
-                            hir_id: pat.hir_id
+                            hir_id: pat.hir_id,
                         }),
                     );
                 }
@@ -542,6 +571,8 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing {
             self.current_body = None;
         }
     }
+
+    extract_msrv_attr!(LateContext);
 }
 
 fn try_parse_ref_op<'tcx>(
@@ -594,6 +625,7 @@ enum Position {
     /// The method is defined on a reference type. e.g. `impl Foo for &T`
     MethodReceiverRefImpl,
     Callee,
+    ImplArg(HirId),
     FieldAccess(Symbol),
     Postfix,
     Deref,
@@ -630,7 +662,7 @@ impl Position {
             | Self::Callee
             | Self::FieldAccess(_)
             | Self::Postfix => PREC_POSTFIX,
-            Self::Deref => PREC_PREFIX,
+            Self::ImplArg(_) | Self::Deref => PREC_PREFIX,
             Self::DerefStable(p, _) | Self::ReborrowStable(p) | Self::Other(p) => p,
         }
     }
@@ -639,8 +671,12 @@ impl Position {
 /// Walks up the parent expressions attempting to determine both how stable the auto-deref result
 /// is, and which adjustments will be applied to it. Note this will not consider auto-borrow
 /// locations as those follow different rules.
-#[allow(clippy::too_many_lines)]
+#[expect(clippy::too_many_lines)]
-fn walk_parents<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> (Position, &'tcx [Adjustment<'tcx>]) {
+fn walk_parents<'tcx>(
+    cx: &LateContext<'tcx>,
+    e: &'tcx Expr<'_>,
+    msrv: Option<RustcVersion>,
+) -> (Position, &'tcx [Adjustment<'tcx>]) {
     let mut adjustments = [].as_slice();
     let mut precedence = 0i8;
     let ctxt = e.span.ctxt();
@@ -745,13 +781,20 @@ fn walk_parents<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> (Position, &
                     .iter()
                     .position(|arg| arg.hir_id == child_id)
                     .zip(expr_sig(cx, func))
-                    .and_then(|(i, sig)| sig.input_with_hir(i))
+                    .and_then(|(i, sig)| {
-                    .map(|(hir_ty, ty)| match hir_ty {
+                        sig.input_with_hir(i).map(|(hir_ty, ty)| match hir_ty {
-                        // Type inference for closures can depend on how they're called. Only go by the explicit
+                            // Type inference for closures can depend on how they're called. Only go by the explicit
-                        // types here.
+                            // types here.
-                        Some(hir_ty) => binding_ty_auto_deref_stability(cx, hir_ty, precedence, ty.bound_vars()),
+                            Some(hir_ty) => binding_ty_auto_deref_stability(cx, hir_ty, precedence, ty.bound_vars()),
-                        None => ty_auto_deref_stability(cx, cx.tcx.erase_late_bound_regions(ty), precedence)
+                            None => {
-                            .position_for_arg(),
+                                if let ty::Param(param_ty) = ty.skip_binder().kind() {
+                                    needless_borrow_impl_arg_position(cx, parent, i, *param_ty, e, precedence, msrv)
+                                } else {
+                                    ty_auto_deref_stability(cx, cx.tcx.erase_late_bound_regions(ty), precedence)
+                                        .position_for_arg()
+                                }
+                            },
+                        })
                     }),
                 ExprKind::MethodCall(_, args, _) => {
                     let id = cx.typeck_results().type_dependent_def_id(parent.hir_id).unwrap();
@@ -773,7 +816,7 @@ fn walk_parents<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> (Position, &
                                     .and_then(|subs| subs.get(1..))
                                 {
                                     Some(subs) => cx.tcx.mk_substs(subs.iter().copied()),
-                                    None => cx.tcx.mk_substs([].iter()),
+                                    None => cx.tcx.mk_substs(std::iter::empty::<ty::subst::GenericArg<'_>>()),
                                 } && let impl_ty = if cx.tcx.fn_sig(id).skip_binder().inputs()[0].is_ref() {
                                     // Trait methods taking `&self`
                                     sub_ty
@@ -792,12 +835,17 @@ fn walk_parents<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> (Position, &
                                 Position::MethodReceiver
                             }
                         } else {
-                            ty_auto_deref_stability(
+                            let ty = cx.tcx.fn_sig(id).skip_binder().inputs()[i];
-                                cx,
+                            if let ty::Param(param_ty) = ty.kind() {
-                                cx.tcx.erase_late_bound_regions(cx.tcx.fn_sig(id).input(i)),
+                                needless_borrow_impl_arg_position(cx, parent, i, *param_ty, e, precedence, msrv)
-                                precedence,
+                            } else {
-                            )
+                                ty_auto_deref_stability(
-                            .position_for_arg()
+                                    cx,
+                                    cx.tcx.erase_late_bound_regions(cx.tcx.fn_sig(id).input(i)),
+                                    precedence,
+                                )
+                                .position_for_arg()
+                            }
                         }
                     })
                 },
@@ -948,6 +996,205 @@ fn ty_contains_infer(ty: &hir::Ty<'_>) -> bool {
     v.0
 }
 
+// Checks whether:
+// * child is an expression of the form `&e` in an argument position requiring an `impl Trait`
+// * `e`'s type implements `Trait` and is copyable
+// If the conditions are met, returns `Some(Position::ImplArg(..))`; otherwise, returns `None`.
+//   The "is copyable" condition is to avoid the case where removing the `&` means `e` would have to
+// be moved, but it cannot be.
+fn needless_borrow_impl_arg_position<'tcx>(
+    cx: &LateContext<'tcx>,
+    parent: &Expr<'tcx>,
+    arg_index: usize,
+    param_ty: ParamTy,
+    mut expr: &Expr<'tcx>,
+    precedence: i8,
+    msrv: Option<RustcVersion>,
+) -> Position {
+    let destruct_trait_def_id = cx.tcx.lang_items().destruct_trait();
+    let sized_trait_def_id = cx.tcx.lang_items().sized_trait();
+
+    let Some(callee_def_id) = fn_def_id(cx, parent) else { return Position::Other(precedence) };
+    let fn_sig = cx.tcx.fn_sig(callee_def_id).skip_binder();
+    let substs_with_expr_ty = cx
+        .typeck_results()
+        .node_substs(if let ExprKind::Call(callee, _) = parent.kind {
+            callee.hir_id
+        } else {
+            parent.hir_id
+        });
+
+    let predicates = cx.tcx.param_env(callee_def_id).caller_bounds();
+    let projection_predicates = predicates
+        .iter()
+        .filter_map(|predicate| {
+            if let PredicateKind::Projection(projection_predicate) = predicate.kind().skip_binder() {
+                Some(projection_predicate)
+            } else {
+                None
+            }
+        })
+        .collect::<Vec<_>>();
+
+    let mut trait_with_ref_mut_self_method = false;
+
+    // If no traits were found, or only the `Destruct`, `Sized`, or `Any` traits were found, return.
+    if predicates
+        .iter()
+        .filter_map(|predicate| {
+            if let PredicateKind::Trait(trait_predicate) = predicate.kind().skip_binder()
+                && trait_predicate.trait_ref.self_ty() == param_ty.to_ty(cx.tcx)
+            {
+                Some(trait_predicate.trait_ref.def_id)
+            } else {
+                None
+            }
+        })
+        .inspect(|trait_def_id| {
+            trait_with_ref_mut_self_method |= has_ref_mut_self_method(cx, *trait_def_id);
+        })
+        .all(|trait_def_id| {
+            Some(trait_def_id) == destruct_trait_def_id
+                || Some(trait_def_id) == sized_trait_def_id
+                || cx.tcx.is_diagnostic_item(sym::Any, trait_def_id)
+        })
+    {
+        return Position::Other(precedence);
+    }
+
+    // `substs_with_referent_ty` can be constructed outside of `check_referent` because the same
+    // elements are modified each time `check_referent` is called.
+    let mut substs_with_referent_ty = substs_with_expr_ty.to_vec();
+
+    let mut check_referent = |referent| {
+        let referent_ty = cx.typeck_results().expr_ty(referent);
+
+        if !is_copy(cx, referent_ty) {
+            return false;
+        }
+
+        // https://github.com/rust-lang/rust-clippy/pull/9136#pullrequestreview-1037379321
+        if trait_with_ref_mut_self_method && !matches!(referent_ty.kind(), ty::Ref(_, _, Mutability::Mut)) {
+            return false;
+        }
+
+        if !replace_types(
+            cx,
+            param_ty,
+            referent_ty,
+            fn_sig,
+            arg_index,
+            &projection_predicates,
+            &mut substs_with_referent_ty,
+        ) {
+            return false;
+        }
+
+        predicates.iter().all(|predicate| {
+            if let PredicateKind::Trait(trait_predicate) = predicate.kind().skip_binder()
+                && cx.tcx.is_diagnostic_item(sym::IntoIterator, trait_predicate.trait_ref.def_id)
+                && let ty::Param(param_ty) = trait_predicate.self_ty().kind()
+                && let GenericArgKind::Type(ty) = substs_with_referent_ty[param_ty.index as usize].unpack()
+                && ty.is_array()
+                && !meets_msrv(msrv, msrvs::ARRAY_INTO_ITERATOR)
+            {
+                return false;
+            }
+
+            let predicate = EarlyBinder(predicate).subst(cx.tcx, &substs_with_referent_ty);
+            let obligation = Obligation::new(ObligationCause::dummy(), cx.param_env, predicate);
+            cx.tcx
+                .infer_ctxt()
+                .enter(|infcx| infcx.predicate_must_hold_modulo_regions(&obligation))
+        })
+    };
+
+    let mut needless_borrow = false;
+    while let ExprKind::AddrOf(_, _, referent) = expr.kind {
+        if !check_referent(referent) {
+            break;
+        }
+        expr = referent;
+        needless_borrow = true;
+    }
+
+    if needless_borrow {
+        Position::ImplArg(expr.hir_id)
+    } else {
+        Position::Other(precedence)
+    }
+}
+
+fn has_ref_mut_self_method(cx: &LateContext<'_>, trait_def_id: DefId) -> bool {
+    cx.tcx
+        .associated_items(trait_def_id)
+        .in_definition_order()
+        .any(|assoc_item| {
+            if assoc_item.fn_has_self_parameter {
+                let self_ty = cx.tcx.fn_sig(assoc_item.def_id).skip_binder().inputs()[0];
+                matches!(self_ty.kind(), ty::Ref(_, _, Mutability::Mut))
+            } else {
+                false
+            }
+        })
+}
+
+// Iteratively replaces `param_ty` with `new_ty` in `substs`, and similarly for each resulting
+// projected type that is a type parameter. Returns `false` if replacing the types would have an
+// effect on the function signature beyond substituting `new_ty` for `param_ty`.
+// See: https://github.com/rust-lang/rust-clippy/pull/9136#discussion_r927212757
+fn replace_types<'tcx>(
+    cx: &LateContext<'tcx>,
+    param_ty: ParamTy,
+    new_ty: Ty<'tcx>,
+    fn_sig: FnSig<'tcx>,
+    arg_index: usize,
+    projection_predicates: &[ProjectionPredicate<'tcx>],
+    substs: &mut [ty::GenericArg<'tcx>],
+) -> bool {
+    let mut replaced = BitSet::new_empty(substs.len());
+
+    let mut deque = VecDeque::with_capacity(substs.len());
+    deque.push_back((param_ty, new_ty));
+
+    while let Some((param_ty, new_ty)) = deque.pop_front() {
+        // If `replaced.is_empty()`, then `param_ty` and `new_ty` are those initially passed in.
+        if !fn_sig
+            .inputs_and_output
+            .iter()
+            .enumerate()
+            .all(|(i, ty)| (replaced.is_empty() && i == arg_index) || !ty.contains(param_ty.to_ty(cx.tcx)))
+        {
+            return false;
+        }
+
+        substs[param_ty.index as usize] = ty::GenericArg::from(new_ty);
+
+        // The `replaced.insert(...)` check provides some protection against infinite loops.
+        if replaced.insert(param_ty.index) {
+            for projection_predicate in projection_predicates {
+                if projection_predicate.projection_ty.self_ty() == param_ty.to_ty(cx.tcx)
+                    && let ty::Term::Ty(term_ty) = projection_predicate.term
+                    && let ty::Param(term_param_ty) = term_ty.kind()
+                {
+                    let item_def_id = projection_predicate.projection_ty.item_def_id;
+                    let assoc_item = cx.tcx.associated_item(item_def_id);
+                    let projection = cx.tcx
+                        .mk_projection(assoc_item.def_id, cx.tcx.mk_substs_trait(new_ty, &[]));
+
+                    if let Ok(projected_ty) = cx.tcx.try_normalize_erasing_regions(cx.param_env, projection)
+                        && substs[term_param_ty.index as usize] != ty::GenericArg::from(projected_ty)
+                    {
+                        deque.push_back((*term_param_ty, projected_ty));
+                    }
+                }
+            }
+        }
+    }
+
+    true
+}
+
 struct TyPosition<'tcx> {
     position: Position,
     ty: Option<Ty<'tcx>>,
@@ -1086,7 +1333,8 @@ fn report<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, state: State, data
         },
         State::DerefedBorrow(state) => {
             let mut app = Applicability::MachineApplicable;
-            let (snip, snip_is_macro) = snippet_with_context(cx, expr.span, data.span.ctxt(), "..", &mut app);
+            let snip_expr = state.snip_expr.map_or(expr, |hir_id| cx.tcx.hir().expect_expr(hir_id));
+            let (snip, snip_is_macro) = snippet_with_context(cx, snip_expr.span, data.span.ctxt(), "..", &mut app);
             span_lint_hir_and_then(cx, NEEDLESS_BORROW, data.hir_id, data.span, state.msg, |diag| {
                 let calls_field = matches!(expr.kind, ExprKind::Field(..)) && matches!(data.position, Position::Callee);
                 let sugg = if !snip_is_macro

src/tools/clippy/clippy_lints/src/derive.rs

@@ -516,7 +516,10 @@ fn param_env_for_derived_eq(tcx: TyCtxt<'_>, did: DefId, eq_trait_id: DefId) ->
         tcx.mk_predicates(ty_predicates.iter().map(|&(p, _)| p).chain(
             params.iter().filter(|&&(_, needs_eq)| needs_eq).map(|&(param, _)| {
                 tcx.mk_predicate(Binder::dummy(PredicateKind::Trait(TraitPredicate {
-                    trait_ref: TraitRef::new(eq_trait_id, tcx.mk_substs([tcx.mk_param_from_def(param)].into_iter())),
+                    trait_ref: TraitRef::new(
+                        eq_trait_id,
+                        tcx.mk_substs(std::iter::once(tcx.mk_param_from_def(param))),
+                    ),
                     constness: BoundConstness::NotConst,
                     polarity: ImplPolarity::Positive,
                 })))

src/tools/clippy/clippy_lints/src/doc_link_with_quotes.rs

@@ -21,7 +21,7 @@ declare_clippy_lint! {
     /// /// See also: [`foo`]
     /// fn bar() {}
     /// ```
-    #[clippy::version = "1.60.0"]
+    #[clippy::version = "1.63.0"]
     pub DOC_LINK_WITH_QUOTES,
     pedantic,
     "possible typo for an intra-doc link"

src/tools/clippy/clippy_lints/src/duplicate_mod.rs

@@ -39,7 +39,7 @@ declare_clippy_lint! {
     /// // a.rs
     /// use crate::b;
     /// ```
-    #[clippy::version = "1.62.0"]
+    #[clippy::version = "1.63.0"]
     pub DUPLICATE_MOD,
     suspicious,
     "file loaded as module multiple times"

src/tools/clippy/clippy_lints/src/escape.rs

@@ -1,5 +1,4 @@
 use clippy_utils::diagnostics::span_lint_hir;
-use clippy_utils::ty::contains_ty;
 use rustc_hir::intravisit;
 use rustc_hir::{self, AssocItemKind, Body, FnDecl, HirId, HirIdSet, Impl, ItemKind, Node, Pat, PatKind};
 use rustc_infer::infer::TyCtxtInferExt;
@@ -30,18 +29,12 @@ declare_clippy_lint! {
     ///
     /// ### Example
     /// ```rust
-    /// # fn foo(bar: usize) {}
+    /// fn foo(x: Box<u32>) {}
-    /// let x = Box::new(1);
-    /// foo(*x);
-    /// println!("{}", *x);
     /// ```
     ///
     /// Use instead:
     /// ```rust
-    /// # fn foo(bar: usize) {}
+    /// fn foo(x: u32) {}
-    /// let x = 1;
-    /// foo(x);
-    /// println!("{}", x);
     /// ```
     #[clippy::version = "pre 1.29.0"]
     pub BOXED_LOCAL,
@@ -172,7 +165,7 @@ impl<'a, 'tcx> Delegate<'tcx> for EscapeDelegate<'a, 'tcx> {
                 // skip if there is a `self` parameter binding to a type
                 // that contains `Self` (i.e.: `self: Box<Self>`), see #4804
                 if let Some(trait_self_ty) = self.trait_self_ty {
-                    if map.name(cmt.hir_id) == kw::SelfLower && contains_ty(cmt.place.ty(), trait_self_ty) {
+                    if map.name(cmt.hir_id) == kw::SelfLower && cmt.place.ty().contains(trait_self_ty) {
                         return;
                     }
                 }

src/tools/clippy/clippy_lints/src/floating_point_arithmetic.rs

@@ -172,7 +172,7 @@ fn check_log_base(cx: &LateContext<'_>, expr: &Expr<'_>, args: &[Expr<'_>]) {
             expr.span,
             "logarithm for bases 2, 10 and e can be computed more accurately",
             "consider using",
-            format!("{}.{}()", Sugg::hir(cx, &args[0], ".."), method),
+            format!("{}.{}()", Sugg::hir(cx, &args[0], "..").maybe_par(), method),
             Applicability::MachineApplicable,
         );
     }
@@ -263,13 +263,13 @@ fn check_powf(cx: &LateContext<'_>, expr: &Expr<'_>, args: &[Expr<'_>]) {
             (
                 SUBOPTIMAL_FLOPS,
                 "square-root of a number can be computed more efficiently and accurately",
-                format!("{}.sqrt()", Sugg::hir(cx, &args[0], "..")),
+                format!("{}.sqrt()", Sugg::hir(cx, &args[0], "..").maybe_par()),
             )
         } else if F32(1.0 / 3.0) == value || F64(1.0 / 3.0) == value {
             (
                 IMPRECISE_FLOPS,
                 "cube-root of a number can be computed more accurately",
-                format!("{}.cbrt()", Sugg::hir(cx, &args[0], "..")),
+                format!("{}.cbrt()", Sugg::hir(cx, &args[0], "..").maybe_par()),
             )
         } else if let Some(exponent) = get_integer_from_float_constant(&value) {
             (
@@ -277,7 +277,7 @@ fn check_powf(cx: &LateContext<'_>, expr: &Expr<'_>, args: &[Expr<'_>]) {
                 "exponentiation with integer powers can be computed more efficiently",
                 format!(
                     "{}.powi({})",
-                    Sugg::hir(cx, &args[0], ".."),
+                    Sugg::hir(cx, &args[0], "..").maybe_par(),
                     numeric_literal::format(&exponent.to_string(), None, false)
                 ),
             )
@@ -327,7 +327,7 @@ fn check_powi(cx: &LateContext<'_>, expr: &Expr<'_>, args: &[Expr<'_>]) {
                         "consider using",
                         format!(
                             "{}.mul_add({}, {})",
-                            Sugg::hir(cx, &args[0], ".."),
+                            Sugg::hir(cx, &args[0], "..").maybe_par(),
                             Sugg::hir(cx, &args[0], ".."),
                             Sugg::hir(cx, other_addend, ".."),
                         ),
@@ -418,7 +418,7 @@ fn check_expm1(cx: &LateContext<'_>, expr: &Expr<'_>) {
                 "consider using",
                 format!(
                     "{}.exp_m1()",
-                    Sugg::hir(cx, self_arg, "..")
+                    Sugg::hir(cx, self_arg, "..").maybe_par()
                 ),
                 Applicability::MachineApplicable,
             );
@@ -550,11 +550,11 @@ fn check_custom_abs(cx: &LateContext<'_>, expr: &Expr<'_>) {
         then {
             let positive_abs_sugg = (
                 "manual implementation of `abs` method",
-                format!("{}.abs()", Sugg::hir(cx, body, "..")),
+                format!("{}.abs()", Sugg::hir(cx, body, "..").maybe_par()),
             );
             let negative_abs_sugg = (
                 "manual implementation of negation of `abs` method",
-                format!("-{}.abs()", Sugg::hir(cx, body, "..")),
+                format!("-{}.abs()", Sugg::hir(cx, body, "..").maybe_par()),
             );
             let sugg = if is_testing_positive(cx, cond, body) {
                 if if_expr_positive {
@@ -621,7 +621,7 @@ fn check_log_division(cx: &LateContext<'_>, expr: &Expr<'_>) {
                 expr.span,
                 "log base can be expressed more clearly",
                 "consider using",
-                format!("{}.log({})", Sugg::hir(cx, largs_self, ".."), Sugg::hir(cx, rargs_self, ".."),),
+                format!("{}.log({})", Sugg::hir(cx, largs_self, "..").maybe_par(), Sugg::hir(cx, rargs_self, ".."),),
                 Applicability::MachineApplicable,
             );
         }
@@ -651,7 +651,7 @@ fn check_radians(cx: &LateContext<'_>, expr: &Expr<'_>) {
             if (F32(f32_consts::PI) == rvalue || F64(f64_consts::PI) == rvalue) &&
                (F32(180_f32) == lvalue || F64(180_f64) == lvalue)
             {
-                let mut proposal = format!("{}.to_degrees()", Sugg::hir(cx, mul_lhs, ".."));
+                let mut proposal = format!("{}.to_degrees()", Sugg::hir(cx, mul_lhs, "..").maybe_par());
                 if_chain! {
                     if let ExprKind::Lit(ref literal) = mul_lhs.kind;
                     if let ast::LitKind::Float(ref value, float_type) = literal.node;
@@ -677,7 +677,7 @@ fn check_radians(cx: &LateContext<'_>, expr: &Expr<'_>) {
                 (F32(180_f32) == rvalue || F64(180_f64) == rvalue) &&
                 (F32(f32_consts::PI) == lvalue || F64(f64_consts::PI) == lvalue)
             {
-                let mut proposal = format!("{}.to_radians()", Sugg::hir(cx, mul_lhs, ".."));
+                let mut proposal = format!("{}.to_radians()", Sugg::hir(cx, mul_lhs, "..").maybe_par());
                 if_chain! {
                     if let ExprKind::Lit(ref literal) = mul_lhs.kind;
                     if let ast::LitKind::Float(ref value, float_type) = literal.node;

src/tools/clippy/clippy_lints/src/format.rs

@@ -1,6 +1,6 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::macros::{root_macro_call_first_node, FormatArgsExpn};
-use clippy_utils::source::{snippet_opt, snippet_with_applicability};
+use clippy_utils::source::snippet_with_applicability;
 use clippy_utils::sugg::Sugg;
 use if_chain::if_chain;
 use rustc_errors::Applicability;
@@ -56,29 +56,27 @@ impl<'tcx> LateLintPass<'tcx> for UselessFormat {
         };
 
         let mut applicability = Applicability::MachineApplicable;
-        if format_args.value_args.is_empty() {
+        if format_args.args.is_empty() {
-            match *format_args.format_string_parts {
+            match *format_args.format_string.parts {
                 [] => span_useless_format_empty(cx, call_site, "String::new()".to_owned(), applicability),
                 [_] => {
-                    if let Some(s_src) = snippet_opt(cx, format_args.format_string_span) {
+                    // Simulate macro expansion, converting {{ and }} to { and }.
-                        // Simulate macro expansion, converting {{ and }} to { and }.
+                    let s_expand = format_args.format_string.snippet.replace("{{", "{").replace("}}", "}");
-                        let s_expand = s_src.replace("{{", "{").replace("}}", "}");
+                    let sugg = format!("{}.to_string()", s_expand);
-                        let sugg = format!("{}.to_string()", s_expand);
+                    span_useless_format(cx, call_site, sugg, applicability);
-                        span_useless_format(cx, call_site, sugg, applicability);
-                    }
                 },
                 [..] => {},
             }
-        } else if let [value] = *format_args.value_args {
+        } else if let [arg] = &*format_args.args {
+            let value = arg.param.value;
             if_chain! {
-                if format_args.format_string_parts == [kw::Empty];
+                if format_args.format_string.parts == [kw::Empty];
                 if match cx.typeck_results().expr_ty(value).peel_refs().kind() {
                     ty::Adt(adt, _) => cx.tcx.is_diagnostic_item(sym::String, adt.did()),
                     ty::Str => true,
                     _ => false,
                 };
-                if let Some(args) = format_args.args();
+                if !arg.format.has_string_formatting();
-                if args.iter().all(|arg| arg.format_trait == sym::Display && !arg.has_string_formatting());
                 then {
                     let is_new_string = match value.kind {
                         ExprKind::Binary(..) => true,

src/tools/clippy/clippy_lints/src/format_args.rs

@@ -1,11 +1,12 @@
 use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_and_then};
 use clippy_utils::is_diag_trait_item;
-use clippy_utils::macros::{is_format_macro, FormatArgsArg, FormatArgsExpn};
+use clippy_utils::macros::{is_format_macro, FormatArgsExpn};
 use clippy_utils::source::snippet_opt;
 use clippy_utils::ty::implements_trait;
 use if_chain::if_chain;
+use itertools::Itertools;
 use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind};
+use rustc_hir::{Expr, ExprKind, HirId};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty::adjustment::{Adjust, Adjustment};
 use rustc_middle::ty::Ty;
@@ -74,20 +75,16 @@ impl<'tcx> LateLintPass<'tcx> for FormatArgs {
             if let Some(macro_def_id) = outermost_expn_data.macro_def_id;
             if is_format_macro(cx, macro_def_id);
             if let ExpnKind::Macro(_, name) = outermost_expn_data.kind;
-            if let Some(args) = format_args.args();
             then {
-                for (i, arg) in args.iter().enumerate() {
+                for arg in &format_args.args {
-                    if arg.format_trait != sym::Display {
+                    if arg.format.has_string_formatting() {
                         continue;
                     }
-                    if arg.has_string_formatting() {
+                    if is_aliased(&format_args, arg.param.value.hir_id) {
                         continue;
                     }
-                    if is_aliased(&args, i) {
+                    check_format_in_format_args(cx, outermost_expn_data.call_site, name, arg.param.value);
-                        continue;
+                    check_to_string_in_format_args(cx, name, arg.param.value);
-                    }
-                    check_format_in_format_args(cx, outermost_expn_data.call_site, name, arg.value);
-                    check_to_string_in_format_args(cx, name, arg.value);
                 }
             }
         }
@@ -134,45 +131,56 @@ fn check_to_string_in_format_args(cx: &LateContext<'_>, name: Symbol, value: &Ex
         if is_diag_trait_item(cx, method_def_id, sym::ToString);
         let receiver_ty = cx.typeck_results().expr_ty(receiver);
         if let Some(display_trait_id) = cx.tcx.get_diagnostic_item(sym::Display);
+        let (n_needed_derefs, target) =
+            count_needed_derefs(receiver_ty, cx.typeck_results().expr_adjustments(receiver).iter());
+        if implements_trait(cx, target, display_trait_id, &[]);
+        if let Some(sized_trait_id) = cx.tcx.lang_items().sized_trait();
         if let Some(receiver_snippet) = snippet_opt(cx, receiver.span);
         then {
-            let (n_needed_derefs, target) = count_needed_derefs(
+            let needs_ref = !implements_trait(cx, receiver_ty, sized_trait_id, &[]);
-                receiver_ty,
+            if n_needed_derefs == 0 && !needs_ref {
-                cx.typeck_results().expr_adjustments(receiver).iter(),
+                span_lint_and_sugg(
-            );
+                    cx,
-            if implements_trait(cx, target, display_trait_id, &[]) {
+                    TO_STRING_IN_FORMAT_ARGS,
-                if n_needed_derefs == 0 {
+                    value.span.with_lo(receiver.span.hi()),
-                    span_lint_and_sugg(
+                    &format!(
-                        cx,
+                        "`to_string` applied to a type that implements `Display` in `{}!` args",
-                        TO_STRING_IN_FORMAT_ARGS,
+                        name
-                        value.span.with_lo(receiver.span.hi()),
+                    ),
-                        &format!("`to_string` applied to a type that implements `Display` in `{}!` args", name),
+                    "remove this",
-                        "remove this",
+                    String::new(),
-                        String::new(),
+                    Applicability::MachineApplicable,
-                        Applicability::MachineApplicable,
+                );
-                    );
+            } else {
-                } else {
+                span_lint_and_sugg(
-                    span_lint_and_sugg(
+                    cx,
-                        cx,
+                    TO_STRING_IN_FORMAT_ARGS,
-                        TO_STRING_IN_FORMAT_ARGS,
+                    value.span,
-                        value.span,
+                    &format!(
-                        &format!("`to_string` applied to a type that implements `Display` in `{}!` args", name),
+                        "`to_string` applied to a type that implements `Display` in `{}!` args",
-                        "use this",
+                        name
-                        format!("{:*>width$}{}", "", receiver_snippet, width = n_needed_derefs),
+                    ),
-                        Applicability::MachineApplicable,
+                    "use this",
-                    );
+                    format!(
-                }
+                        "{}{:*>width$}{}",
+                        if needs_ref { "&" } else { "" },
+                        "",
+                        receiver_snippet,
+                        width = n_needed_derefs
+                    ),
+                    Applicability::MachineApplicable,
+                );
             }
         }
     }
 }
 
-// Returns true if `args[i]` "refers to" or "is referred to by" another argument.
+// Returns true if `hir_id` is referred to by multiple format params
-fn is_aliased(args: &[FormatArgsArg<'_>], i: usize) -> bool {
+fn is_aliased(args: &FormatArgsExpn<'_>, hir_id: HirId) -> bool {
-    let value = args[i].value;
+    args.params()
-    args.iter()
+        .filter(|param| param.value.hir_id == hir_id)
-        .enumerate()
+        .at_most_one()
-        .any(|(j, arg)| i != j && std::ptr::eq(value, arg.value))
+        .is_err()
 }
 
 fn count_needed_derefs<'tcx, I>(mut ty: Ty<'tcx>, mut iter: I) -> (usize, Ty<'tcx>)

src/tools/clippy/clippy_lints/src/format_impl.rs

@@ -1,5 +1,5 @@
 use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg};
-use clippy_utils::macros::{is_format_macro, root_macro_call_first_node, FormatArgsArg, FormatArgsExpn};
+use clippy_utils::macros::{is_format_macro, root_macro_call_first_node, FormatArg, FormatArgsExpn};
 use clippy_utils::{get_parent_as_impl, is_diag_trait_item, path_to_local, peel_ref_operators};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
@@ -168,10 +168,9 @@ fn check_self_in_format_args<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>,
         if let macro_def_id = outer_macro.def_id;
         if let Some(format_args) = FormatArgsExpn::find_nested(cx, expr, outer_macro.expn);
         if is_format_macro(cx, macro_def_id);
-        if let Some(args) = format_args.args();
         then {
-            for arg in args {
+            for arg in format_args.args {
-                if arg.format_trait != impl_trait.name {
+                if arg.format.r#trait != impl_trait.name {
                     continue;
                 }
                 check_format_arg_self(cx, expr, &arg, impl_trait);
@@ -180,11 +179,11 @@ fn check_self_in_format_args<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>,
     }
 }
 
-fn check_format_arg_self(cx: &LateContext<'_>, expr: &Expr<'_>, arg: &FormatArgsArg<'_>, impl_trait: FormatTrait) {
+fn check_format_arg_self(cx: &LateContext<'_>, expr: &Expr<'_>, arg: &FormatArg<'_>, impl_trait: FormatTrait) {
     // Handle multiple dereferencing of references e.g. &&self
     // Handle dereference of &self -> self that is equivalent (i.e. via *self in fmt() impl)
     // Since the argument to fmt is itself a reference: &self
-    let reference = peel_ref_operators(cx, arg.value);
+    let reference = peel_ref_operators(cx, arg.param.value);
     let map = cx.tcx.hir();
     // Is the reference self?
     if path_to_local(reference).map(|x| map.name(x)) == Some(kw::SelfLower) {

src/tools/clippy/clippy_lints/src/functions/mod.rs

@@ -1,6 +1,6 @@
 mod must_use;
 mod not_unsafe_ptr_arg_deref;
-mod result_unit_err;
+mod result;
 mod too_many_arguments;
 mod too_many_lines;
 
@@ -217,17 +217,62 @@ declare_clippy_lint! {
     "public function returning `Result` with an `Err` type of `()`"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for functions that return `Result` with an unusually large
+    /// `Err`-variant.
+    ///
+    /// ### Why is this bad?
+    /// A `Result` is at least as large as the `Err`-variant. While we
+    /// expect that variant to be seldomly used, the compiler needs to reserve
+    /// and move that much memory every single time.
+    ///
+    /// ### Known problems
+    /// The size determined by Clippy is platform-dependent.
+    ///
+    /// ### Examples
+    /// ```rust
+    /// pub enum ParseError {
+    ///     UnparsedBytes([u8; 512]),
+    ///     UnexpectedEof,
+    /// }
+    ///
+    /// // The `Result` has at least 512 bytes, even in the `Ok`-case
+    /// pub fn parse() -> Result<(), ParseError> {
+    ///     Ok(())
+    /// }
+    /// ```
+    /// should be
+    /// ```
+    /// pub enum ParseError {
+    ///     UnparsedBytes(Box<[u8; 512]>),
+    ///     UnexpectedEof,
+    /// }
+    ///
+    /// // The `Result` is slightly larger than a pointer
+    /// pub fn parse() -> Result<(), ParseError> {
+    ///     Ok(())
+    /// }
+    /// ```
+    #[clippy::version = "1.64.0"]
+    pub RESULT_LARGE_ERR,
+    perf,
+    "function returning `Result` with large `Err` type"
+}
+
 #[derive(Copy, Clone)]
 pub struct Functions {
     too_many_arguments_threshold: u64,
     too_many_lines_threshold: u64,
+    large_error_threshold: u64,
 }
 
 impl Functions {
-    pub fn new(too_many_arguments_threshold: u64, too_many_lines_threshold: u64) -> Self {
+    pub fn new(too_many_arguments_threshold: u64, too_many_lines_threshold: u64, large_error_threshold: u64) -> Self {
         Self {
             too_many_arguments_threshold,
             too_many_lines_threshold,
+            large_error_threshold,
         }
     }
 }
@@ -240,6 +285,7 @@ impl_lint_pass!(Functions => [
     DOUBLE_MUST_USE,
     MUST_USE_CANDIDATE,
     RESULT_UNIT_ERR,
+    RESULT_LARGE_ERR,
 ]);
 
 impl<'tcx> LateLintPass<'tcx> for Functions {
@@ -259,18 +305,18 @@ impl<'tcx> LateLintPass<'tcx> for Functions {
 
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>) {
         must_use::check_item(cx, item);
-        result_unit_err::check_item(cx, item);
+        result::check_item(cx, item, self.large_error_threshold);
     }
 
     fn check_impl_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::ImplItem<'_>) {
         must_use::check_impl_item(cx, item);
-        result_unit_err::check_impl_item(cx, item);
+        result::check_impl_item(cx, item, self.large_error_threshold);
     }
 
     fn check_trait_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::TraitItem<'_>) {
         too_many_arguments::check_trait_item(cx, item, self.too_many_arguments_threshold);
         not_unsafe_ptr_arg_deref::check_trait_item(cx, item);
         must_use::check_trait_item(cx, item);
-        result_unit_err::check_trait_item(cx, item);
+        result::check_trait_item(cx, item, self.large_error_threshold);
     }
 }

src/tools/clippy/clippy_lints/src/functions/result.rs

@@ -0,0 +1,100 @@
+use rustc_errors::Diagnostic;
+use rustc_hir as hir;
+use rustc_lint::{LateContext, LintContext};
+use rustc_middle::lint::in_external_macro;
+use rustc_middle::ty::{self, Ty};
+use rustc_span::{sym, Span};
+use rustc_typeck::hir_ty_to_ty;
+
+use clippy_utils::diagnostics::{span_lint_and_help, span_lint_and_then};
+use clippy_utils::trait_ref_of_method;
+use clippy_utils::ty::{approx_ty_size, is_type_diagnostic_item};
+
+use super::{RESULT_LARGE_ERR, RESULT_UNIT_ERR};
+
+/// The type of the `Err`-variant in a `std::result::Result` returned by the
+/// given `FnDecl`
+fn result_err_ty<'tcx>(
+    cx: &LateContext<'tcx>,
+    decl: &hir::FnDecl<'tcx>,
+    item_span: Span,
+) -> Option<(&'tcx hir::Ty<'tcx>, Ty<'tcx>)> {
+    if !in_external_macro(cx.sess(), item_span)
+        && let hir::FnRetTy::Return(hir_ty) = decl.output
+        && let ty = hir_ty_to_ty(cx.tcx, hir_ty)
+        && is_type_diagnostic_item(cx, ty, sym::Result)
+        && let ty::Adt(_, substs) = ty.kind()
+    {
+        let err_ty = substs.type_at(1);
+        Some((hir_ty, err_ty))
+    } else {
+        None
+    }
+}
+
+pub(super) fn check_item<'tcx>(cx: &LateContext<'tcx>, item: &hir::Item<'tcx>, large_err_threshold: u64) {
+    if let hir::ItemKind::Fn(ref sig, _generics, _) = item.kind
+        && let Some((hir_ty, err_ty)) = result_err_ty(cx, sig.decl, item.span)
+    {
+        if cx.access_levels.is_exported(item.def_id) {
+            let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
+            check_result_unit_err(cx, err_ty, fn_header_span);
+        }
+        check_result_large_err(cx, err_ty, hir_ty.span, large_err_threshold);
+    }
+}
+
+pub(super) fn check_impl_item<'tcx>(cx: &LateContext<'tcx>, item: &hir::ImplItem<'tcx>, large_err_threshold: u64) {
+    // Don't lint if method is a trait's implementation, we can't do anything about those
+    if let hir::ImplItemKind::Fn(ref sig, _) = item.kind
+        && let Some((hir_ty, err_ty)) = result_err_ty(cx, sig.decl, item.span)
+        && trait_ref_of_method(cx, item.def_id).is_none()
+    {
+        if cx.access_levels.is_exported(item.def_id) {
+            let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
+            check_result_unit_err(cx, err_ty, fn_header_span);
+        }
+        check_result_large_err(cx, err_ty, hir_ty.span, large_err_threshold);
+    }
+}
+
+pub(super) fn check_trait_item<'tcx>(cx: &LateContext<'tcx>, item: &hir::TraitItem<'tcx>, large_err_threshold: u64) {
+    if let hir::TraitItemKind::Fn(ref sig, _) = item.kind {
+        let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
+        if let Some((hir_ty, err_ty)) = result_err_ty(cx, sig.decl, item.span) {
+            if cx.access_levels.is_exported(item.def_id) {
+                check_result_unit_err(cx, err_ty, fn_header_span);
+            }
+            check_result_large_err(cx, err_ty, hir_ty.span, large_err_threshold);
+        }
+    }
+}
+
+fn check_result_unit_err(cx: &LateContext<'_>, err_ty: Ty<'_>, fn_header_span: Span) {
+    if err_ty.is_unit() {
+        span_lint_and_help(
+            cx,
+            RESULT_UNIT_ERR,
+            fn_header_span,
+            "this returns a `Result<_, ()>`",
+            None,
+            "use a custom `Error` type instead",
+        );
+    }
+}
+
+fn check_result_large_err<'tcx>(cx: &LateContext<'tcx>, err_ty: Ty<'tcx>, hir_ty_span: Span, large_err_threshold: u64) {
+    let ty_size = approx_ty_size(cx, err_ty);
+    if ty_size >= large_err_threshold {
+        span_lint_and_then(
+            cx,
+            RESULT_LARGE_ERR,
+            hir_ty_span,
+            "the `Err`-variant returned from this function is very large",
+            |diag: &mut Diagnostic| {
+                diag.span_label(hir_ty_span, format!("the `Err`-variant is at least {ty_size} bytes"));
+                diag.help(format!("try reducing the size of `{err_ty}`, for example by boxing large elements or replacing it with `Box<{err_ty}>`"));
+            },
+        );
+    }
+}

src/tools/clippy/clippy_lints/src/functions/result_unit_err.rs

@@ -1,66 +0,0 @@
-use rustc_hir as hir;
-use rustc_lint::{LateContext, LintContext};
-use rustc_middle::lint::in_external_macro;
-use rustc_middle::ty;
-use rustc_span::{sym, Span};
-use rustc_typeck::hir_ty_to_ty;
-
-use if_chain::if_chain;
-
-use clippy_utils::diagnostics::span_lint_and_help;
-use clippy_utils::trait_ref_of_method;
-use clippy_utils::ty::is_type_diagnostic_item;
-
-use super::RESULT_UNIT_ERR;
-
-pub(super) fn check_item(cx: &LateContext<'_>, item: &hir::Item<'_>) {
-    if let hir::ItemKind::Fn(ref sig, _generics, _) = item.kind {
-        let is_public = cx.access_levels.is_exported(item.def_id);
-        let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
-        if is_public {
-            check_result_unit_err(cx, sig.decl, item.span, fn_header_span);
-        }
-    }
-}
-
-pub(super) fn check_impl_item(cx: &LateContext<'_>, item: &hir::ImplItem<'_>) {
-    if let hir::ImplItemKind::Fn(ref sig, _) = item.kind {
-        let is_public = cx.access_levels.is_exported(item.def_id);
-        let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
-        if is_public && trait_ref_of_method(cx, item.def_id).is_none() {
-            check_result_unit_err(cx, sig.decl, item.span, fn_header_span);
-        }
-    }
-}
-
-pub(super) fn check_trait_item(cx: &LateContext<'_>, item: &hir::TraitItem<'_>) {
-    if let hir::TraitItemKind::Fn(ref sig, _) = item.kind {
-        let is_public = cx.access_levels.is_exported(item.def_id);
-        let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
-        if is_public {
-            check_result_unit_err(cx, sig.decl, item.span, fn_header_span);
-        }
-    }
-}
-
-fn check_result_unit_err(cx: &LateContext<'_>, decl: &hir::FnDecl<'_>, item_span: Span, fn_header_span: Span) {
-    if_chain! {
-        if !in_external_macro(cx.sess(), item_span);
-        if let hir::FnRetTy::Return(ty) = decl.output;
-        let ty = hir_ty_to_ty(cx.tcx, ty);
-        if is_type_diagnostic_item(cx, ty, sym::Result);
-        if let ty::Adt(_, substs) = ty.kind();
-        let err_ty = substs.type_at(1);
-        if err_ty.is_unit();
-        then {
-            span_lint_and_help(
-                cx,
-                RESULT_UNIT_ERR,
-                fn_header_span,
-                "this returns a `Result<_, ()>`",
-                None,
-                "use a custom `Error` type instead",
-            );
-        }
-    }
-}

src/tools/clippy/clippy_lints/src/get_first.rs

@@ -1,68 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet_with_applicability;
-use clippy_utils::{is_slice_of_primitives, match_def_path, paths};
-use if_chain::if_chain;
-use rustc_ast::LitKind;
-use rustc_errors::Applicability;
-use rustc_hir as hir;
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::source_map::Spanned;
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for using `x.get(0)` instead of
-    /// `x.first()`.
-    ///
-    /// ### Why is this bad?
-    /// Using `x.first()` is easier to read and has the same
-    /// result.
-    ///
-    /// ### Example
-    /// ```rust
-    /// let x = vec![2, 3, 5];
-    /// let first_element = x.get(0);
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust
-    /// let x = vec![2, 3, 5];
-    /// let first_element = x.first();
-    /// ```
-    #[clippy::version = "1.63.0"]
-    pub GET_FIRST,
-    style,
-    "Using `x.get(0)` when `x.first()` is simpler"
-}
-declare_lint_pass!(GetFirst => [GET_FIRST]);
-
-impl<'tcx> LateLintPass<'tcx> for GetFirst {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) {
-        if_chain! {
-            if let hir::ExprKind::MethodCall(_, [struct_calling_on, method_arg], _) = &expr.kind;
-            if let Some(expr_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
-            if match_def_path(cx, expr_def_id, &paths::SLICE_GET);
-
-            if let Some(_) = is_slice_of_primitives(cx, struct_calling_on);
-            if let hir::ExprKind::Lit(Spanned { node: LitKind::Int(0, _), .. }) = method_arg.kind;
-
-            then {
-                let mut applicability = Applicability::MachineApplicable;
-                let slice_name = snippet_with_applicability(
-                    cx,
-                    struct_calling_on.span, "..",
-                    &mut applicability,
-                );
-                span_lint_and_sugg(
-                    cx,
-                    GET_FIRST,
-                    expr.span,
-                    &format!("accessing first element with `{0}.get(0)`", slice_name),
-                    "try",
-                    format!("{}.first()", slice_name),
-                    applicability,
-                );
-            }
-        }
-    }
-}

src/tools/clippy/clippy_lints/src/if_let_mutex.rs

@@ -1,8 +1,9 @@
-use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::higher;
 use clippy_utils::ty::is_type_diagnostic_item;
 use clippy_utils::SpanlessEq;
 use if_chain::if_chain;
+use rustc_errors::Diagnostic;
 use rustc_hir::intravisit::{self as visit, Visitor};
 use rustc_hir::{Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass};
@@ -45,16 +46,8 @@ declare_lint_pass!(IfLetMutex => [IF_LET_MUTEX]);
 
 impl<'tcx> LateLintPass<'tcx> for IfLetMutex {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
-        let mut arm_visit = ArmVisitor {
+        let mut arm_visit = ArmVisitor { found_mutex: None, cx };
-            mutex_lock_called: false,
+        let mut op_visit = OppVisitor { found_mutex: None, cx };
-            found_mutex: None,
-            cx,
-        };
-        let mut op_visit = OppVisitor {
-            mutex_lock_called: false,
-            found_mutex: None,
-            cx,
-        };
         if let Some(higher::IfLet {
             let_expr,
             if_then,
@@ -63,18 +56,28 @@ impl<'tcx> LateLintPass<'tcx> for IfLetMutex {
         }) = higher::IfLet::hir(cx, expr)
         {
             op_visit.visit_expr(let_expr);
-            if op_visit.mutex_lock_called {
+            if let Some(op_mutex) = op_visit.found_mutex {
                 arm_visit.visit_expr(if_then);
                 arm_visit.visit_expr(if_else);
 
-                if arm_visit.mutex_lock_called && arm_visit.same_mutex(cx, op_visit.found_mutex.unwrap()) {
+                if let Some(arm_mutex) = arm_visit.found_mutex_if_same_as(op_mutex) {
-                    span_lint_and_help(
+                    let diag = |diag: &mut Diagnostic| {
+                        diag.span_label(
+                            op_mutex.span,
+                            "this Mutex will remain locked for the entire `if let`-block...",
+                        );
+                        diag.span_label(
+                            arm_mutex.span,
+                            "... and is tried to lock again here, which will always deadlock.",
+                        );
+                        diag.help("move the lock call outside of the `if let ...` expression");
+                    };
+                    span_lint_and_then(
                         cx,
                         IF_LET_MUTEX,
                         expr.span,
                         "calling `Mutex::lock` inside the scope of another `Mutex::lock` causes a deadlock",
-                        None,
+                        diag,
-                        "move the lock call outside of the `if let ...` expression",
                     );
                 }
             }
@@ -84,7 +87,6 @@ impl<'tcx> LateLintPass<'tcx> for IfLetMutex {
 
 /// Checks if `Mutex::lock` is called in the `if let` expr.
 pub struct OppVisitor<'a, 'tcx> {
-    mutex_lock_called: bool,
     found_mutex: Option<&'tcx Expr<'tcx>>,
     cx: &'a LateContext<'tcx>,
 }
@@ -93,7 +95,6 @@ impl<'tcx> Visitor<'tcx> for OppVisitor<'_, 'tcx> {
     fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
         if let Some(mutex) = is_mutex_lock_call(self.cx, expr) {
             self.found_mutex = Some(mutex);
-            self.mutex_lock_called = true;
             return;
         }
         visit::walk_expr(self, expr);
@@ -102,7 +103,6 @@ impl<'tcx> Visitor<'tcx> for OppVisitor<'_, 'tcx> {
 
 /// Checks if `Mutex::lock` is called in any of the branches.
 pub struct ArmVisitor<'a, 'tcx> {
-    mutex_lock_called: bool,
     found_mutex: Option<&'tcx Expr<'tcx>>,
     cx: &'a LateContext<'tcx>,
 }
@@ -111,7 +111,6 @@ impl<'tcx> Visitor<'tcx> for ArmVisitor<'_, 'tcx> {
     fn visit_expr(&mut self, expr: &'tcx Expr<'tcx>) {
         if let Some(mutex) = is_mutex_lock_call(self.cx, expr) {
             self.found_mutex = Some(mutex);
-            self.mutex_lock_called = true;
             return;
         }
         visit::walk_expr(self, expr);
@@ -119,9 +118,12 @@ impl<'tcx> Visitor<'tcx> for ArmVisitor<'_, 'tcx> {
 }
 
 impl<'tcx, 'l> ArmVisitor<'tcx, 'l> {
-    fn same_mutex(&self, cx: &LateContext<'_>, op_mutex: &Expr<'_>) -> bool {
+    fn found_mutex_if_same_as(&self, op_mutex: &Expr<'_>) -> Option<&Expr<'_>> {
-        self.found_mutex
+        self.found_mutex.and_then(|arm_mutex| {
-            .map_or(false, |arm_mutex| SpanlessEq::new(cx).eq_expr(op_mutex, arm_mutex))
+            SpanlessEq::new(self.cx)
+                .eq_expr(op_mutex, arm_mutex)
+                .then_some(arm_mutex)
+        })
     }
 }
 
@@ -129,7 +131,7 @@ fn is_mutex_lock_call<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Opt
     if_chain! {
         if let ExprKind::MethodCall(path, [self_arg, ..], _) = &expr.kind;
         if path.ident.as_str() == "lock";
-        let ty = cx.typeck_results().expr_ty(self_arg);
+        let ty = cx.typeck_results().expr_ty(self_arg).peel_refs();
         if is_type_diagnostic_item(cx, ty, sym::Mutex);
         then {
             Some(self_arg)

src/tools/clippy/clippy_lints/src/if_then_some_else_none.rs

@@ -1,7 +1,7 @@
 use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::eager_or_lazy::switch_to_eager_eval;
 use clippy_utils::source::snippet_with_macro_callsite;
 use clippy_utils::{contains_return, higher, is_else_clause, is_lang_ctor, meets_msrv, msrvs, peel_blocks};
-use if_chain::if_chain;
 use rustc_hir::LangItem::{OptionNone, OptionSome};
 use rustc_hir::{Expr, ExprKind, Stmt, StmtKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
@@ -11,10 +11,12 @@ use rustc_session::{declare_tool_lint, impl_lint_pass};
 
 declare_clippy_lint! {
     /// ### What it does
-    /// Checks for if-else that could be written to `bool::then`.
+    /// Checks for if-else that could be written using either `bool::then` or `bool::then_some`.
     ///
     /// ### Why is this bad?
-    /// Looks a little redundant. Using `bool::then` helps it have less lines of code.
+    /// Looks a little redundant. Using `bool::then` is more concise and incurs no loss of clarity.
+    /// For simple calculations and known values, use `bool::then_some`, which is eagerly evaluated
+    /// in comparison to `bool::then`.
     ///
     /// ### Example
     /// ```rust
@@ -39,7 +41,7 @@ declare_clippy_lint! {
     #[clippy::version = "1.53.0"]
     pub IF_THEN_SOME_ELSE_NONE,
     restriction,
-    "Finds if-else that could be written using `bool::then`"
+    "Finds if-else that could be written using either `bool::then` or `bool::then_some`"
 }
 
 pub struct IfThenSomeElseNone {
@@ -56,7 +58,7 @@ impl IfThenSomeElseNone {
 impl_lint_pass!(IfThenSomeElseNone => [IF_THEN_SOME_ELSE_NONE]);
 
 impl<'tcx> LateLintPass<'tcx> for IfThenSomeElseNone {
-    fn check_expr(&mut self, cx: &LateContext<'_>, expr: &'tcx Expr<'_>) {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
         if !meets_msrv(self.msrv, msrvs::BOOL_THEN) {
             return;
         }
@@ -70,43 +72,47 @@ impl<'tcx> LateLintPass<'tcx> for IfThenSomeElseNone {
             return;
         }
 
-        if_chain! {
+        if let Some(higher::If { cond, then, r#else: Some(els) }) = higher::If::hir(expr)
-            if let Some(higher::If { cond, then, r#else: Some(els) }) = higher::If::hir(expr);
+            && let ExprKind::Block(then_block, _) = then.kind
-            if let ExprKind::Block(then_block, _) = then.kind;
+            && let Some(then_expr) = then_block.expr
-            if let Some(then_expr) = then_block.expr;
+            && let ExprKind::Call(then_call, [then_arg]) = then_expr.kind
-            if let ExprKind::Call(then_call, [then_arg]) = then_expr.kind;
+            && let ExprKind::Path(ref then_call_qpath) = then_call.kind
-            if let ExprKind::Path(ref then_call_qpath) = then_call.kind;
+            && is_lang_ctor(cx, then_call_qpath, OptionSome)
-            if is_lang_ctor(cx, then_call_qpath, OptionSome);
+            && let ExprKind::Path(ref qpath) = peel_blocks(els).kind
-            if let ExprKind::Path(ref qpath) = peel_blocks(els).kind;
+            && is_lang_ctor(cx, qpath, OptionNone)
-            if is_lang_ctor(cx, qpath, OptionNone);
+            && !stmts_contains_early_return(then_block.stmts)
-            if !stmts_contains_early_return(then_block.stmts);
+        {
-            then {
+            let cond_snip = snippet_with_macro_callsite(cx, cond.span, "[condition]");
-                let cond_snip = snippet_with_macro_callsite(cx, cond.span, "[condition]");
+            let cond_snip = if matches!(cond.kind, ExprKind::Unary(_, _) | ExprKind::Binary(_, _, _)) {
-                let cond_snip = if matches!(cond.kind, ExprKind::Unary(_, _) | ExprKind::Binary(_, _, _)) {
+                format!("({})", cond_snip)
-                    format!("({})", cond_snip)
+            } else {
-                } else {
+                cond_snip.into_owned()
-                    cond_snip.into_owned()
+            };
-                };
+            let arg_snip = snippet_with_macro_callsite(cx, then_arg.span, "");
-                let arg_snip = snippet_with_macro_callsite(cx, then_arg.span, "");
+            let mut method_body = if then_block.stmts.is_empty() {
-                let closure_body = if then_block.stmts.is_empty() {
+                arg_snip.into_owned()
-                    arg_snip.into_owned()
+            } else {
-                } else {
+                format!("{{ /* snippet */ {} }}", arg_snip)
-                    format!("{{ /* snippet */ {} }}", arg_snip)
+            };
-                };
+            let method_name = if switch_to_eager_eval(cx, expr) && meets_msrv(self.msrv, msrvs::BOOL_THEN_SOME) {
-                let help = format!(
+                "then_some"
-                    "consider using `bool::then` like: `{}.then(|| {})`",
+            } else {
-                    cond_snip,
+                method_body.insert_str(0, "|| ");
-                    closure_body,
+                "then"
-                );
+            };
-                span_lint_and_help(
+
-                    cx,
+            let help = format!(
-                    IF_THEN_SOME_ELSE_NONE,
+                "consider using `bool::{}` like: `{}.{}({})`",
-                    expr.span,
+                method_name, cond_snip, method_name, method_body,
-                    "this could be simplified with `bool::then`",
+            );
-                    None,
+            span_lint_and_help(
-                    &help,
+                cx,
-                );
+                IF_THEN_SOME_ELSE_NONE,
-            }
+                expr.span,
+                &format!("this could be simplified with `bool::{}`", method_name),
+                None,
+                &help,
+            );
         }
     }
 

src/tools/clippy/clippy_lints/src/lib.register_all.rs

@@ -20,12 +20,12 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(booleans::NONMINIMAL_BOOL),
     LintId::of(booleans::OVERLY_COMPLEX_BOOL_EXPR),
     LintId::of(borrow_deref_ref::BORROW_DEREF_REF),
-    LintId::of(bytes_count_to_len::BYTES_COUNT_TO_LEN),
     LintId::of(casts::CAST_ABS_TO_UNSIGNED),
     LintId::of(casts::CAST_ENUM_CONSTRUCTOR),
     LintId::of(casts::CAST_ENUM_TRUNCATION),
     LintId::of(casts::CAST_REF_TO_MUT),
     LintId::of(casts::CAST_SLICE_DIFFERENT_SIZES),
+    LintId::of(casts::CAST_SLICE_FROM_RAW_PARTS),
     LintId::of(casts::CHAR_LIT_AS_U8),
     LintId::of(casts::FN_TO_NUMERIC_CAST),
     LintId::of(casts::FN_TO_NUMERIC_CAST_WITH_TRUNCATION),
@@ -80,9 +80,9 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(functions::DOUBLE_MUST_USE),
     LintId::of(functions::MUST_USE_UNIT),
     LintId::of(functions::NOT_UNSAFE_PTR_ARG_DEREF),
+    LintId::of(functions::RESULT_LARGE_ERR),
     LintId::of(functions::RESULT_UNIT_ERR),
     LintId::of(functions::TOO_MANY_ARGUMENTS),
-    LintId::of(get_first::GET_FIRST),
     LintId::of(if_let_mutex::IF_LET_MUTEX),
     LintId::of(indexing_slicing::OUT_OF_BOUNDS_INDEXING),
     LintId::of(infinite_iter::INFINITE_ITER),
@@ -128,7 +128,6 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(manual_rem_euclid::MANUAL_REM_EUCLID),
     LintId::of(manual_retain::MANUAL_RETAIN),
     LintId::of(manual_strip::MANUAL_STRIP),
-    LintId::of(map_clone::MAP_CLONE),
     LintId::of(map_unit_fn::OPTION_MAP_UNIT_FN),
     LintId::of(map_unit_fn::RESULT_MAP_UNIT_FN),
     LintId::of(match_result_ok::MATCH_RESULT_OK),
@@ -150,17 +149,20 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(mem_replace::MEM_REPLACE_WITH_DEFAULT),
     LintId::of(mem_replace::MEM_REPLACE_WITH_UNINIT),
     LintId::of(methods::BIND_INSTEAD_OF_MAP),
+    LintId::of(methods::BYTES_COUNT_TO_LEN),
     LintId::of(methods::BYTES_NTH),
     LintId::of(methods::CHARS_LAST_CMP),
     LintId::of(methods::CHARS_NEXT_CMP),
     LintId::of(methods::CLONE_DOUBLE_REF),
     LintId::of(methods::CLONE_ON_COPY),
+    LintId::of(methods::COLLAPSIBLE_STR_REPLACE),
     LintId::of(methods::ERR_EXPECT),
     LintId::of(methods::EXPECT_FUN_CALL),
     LintId::of(methods::EXTEND_WITH_DRAIN),
     LintId::of(methods::FILTER_MAP_IDENTITY),
     LintId::of(methods::FILTER_NEXT),
     LintId::of(methods::FLAT_MAP_IDENTITY),
+    LintId::of(methods::GET_FIRST),
     LintId::of(methods::GET_LAST_WITH_LEN),
     LintId::of(methods::INSPECT_FOR_EACH),
     LintId::of(methods::INTO_ITER_ON_REF),
@@ -178,13 +180,16 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(methods::MANUAL_SATURATING_ARITHMETIC),
     LintId::of(methods::MANUAL_SPLIT_ONCE),
     LintId::of(methods::MANUAL_STR_REPEAT),
+    LintId::of(methods::MAP_CLONE),
     LintId::of(methods::MAP_COLLECT_RESULT_UNIT),
     LintId::of(methods::MAP_FLATTEN),
     LintId::of(methods::MAP_IDENTITY),
+    LintId::of(methods::MUT_MUTEX_LOCK),
     LintId::of(methods::NEEDLESS_OPTION_AS_DEREF),
     LintId::of(methods::NEEDLESS_OPTION_TAKE),
     LintId::of(methods::NEEDLESS_SPLITN),
     LintId::of(methods::NEW_RET_NO_SELF),
+    LintId::of(methods::NONSENSICAL_OPEN_OPTIONS),
     LintId::of(methods::NO_EFFECT_REPLACE),
     LintId::of(methods::OBFUSCATED_IF_ELSE),
     LintId::of(methods::OK_EXPECT),
@@ -193,6 +198,8 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(methods::OPTION_MAP_OR_NONE),
     LintId::of(methods::OR_FUN_CALL),
     LintId::of(methods::OR_THEN_UNWRAP),
+    LintId::of(methods::RANGE_ZIP_WITH_LEN),
+    LintId::of(methods::REPEAT_ONCE),
     LintId::of(methods::RESULT_MAP_OR_INTO_OPTION),
     LintId::of(methods::SEARCH_IS_SOME),
     LintId::of(methods::SHOULD_IMPLEMENT_TRAIT),
@@ -202,14 +209,18 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(methods::STRING_EXTEND_CHARS),
     LintId::of(methods::SUSPICIOUS_MAP),
     LintId::of(methods::SUSPICIOUS_SPLITN),
+    LintId::of(methods::SUSPICIOUS_TO_OWNED),
     LintId::of(methods::UNINIT_ASSUMED_INIT),
+    LintId::of(methods::UNIT_HASH),
     LintId::of(methods::UNNECESSARY_FILTER_MAP),
     LintId::of(methods::UNNECESSARY_FIND_MAP),
     LintId::of(methods::UNNECESSARY_FOLD),
     LintId::of(methods::UNNECESSARY_LAZY_EVALUATIONS),
+    LintId::of(methods::UNNECESSARY_SORT_BY),
     LintId::of(methods::UNNECESSARY_TO_OWNED),
     LintId::of(methods::UNWRAP_OR_ELSE_DEFAULT),
     LintId::of(methods::USELESS_ASREF),
+    LintId::of(methods::VEC_RESIZE_TO_ZERO),
     LintId::of(methods::WRONG_SELF_CONVENTION),
     LintId::of(methods::ZST_OFFSET),
     LintId::of(minmax::MIN_MAX),
@@ -224,8 +235,8 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(misc_early::UNNEEDED_WILDCARD_PATTERN),
     LintId::of(misc_early::ZERO_PREFIXED_LITERAL),
     LintId::of(mixed_read_write_in_expression::DIVERGING_SUB_EXPRESSION),
+    LintId::of(multi_assignments::MULTI_ASSIGNMENTS),
     LintId::of(mut_key::MUTABLE_KEY_TYPE),
-    LintId::of(mut_mutex_lock::MUT_MUTEX_LOCK),
     LintId::of(mut_reference::UNNECESSARY_MUT_PASSED),
     LintId::of(needless_arbitrary_self_type::NEEDLESS_ARBITRARY_SELF_TYPE),
     LintId::of(needless_bool::BOOL_COMPARISON),
@@ -245,7 +256,7 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(non_expressive_names::JUST_UNDERSCORES_AND_DIGITS),
     LintId::of(non_octal_unix_permissions::NON_OCTAL_UNIX_PERMISSIONS),
     LintId::of(octal_escapes::OCTAL_ESCAPES),
-    LintId::of(open_options::NONSENSICAL_OPEN_OPTIONS),
+    LintId::of(only_used_in_recursion::ONLY_USED_IN_RECURSION),
     LintId::of(operators::ABSURD_EXTREME_COMPARISONS),
     LintId::of(operators::ASSIGN_OP_PATTERN),
     LintId::of(operators::BAD_BIT_MASK),
@@ -275,7 +286,6 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(ptr_offset_with_cast::PTR_OFFSET_WITH_CAST),
     LintId::of(question_mark::QUESTION_MARK),
     LintId::of(ranges::MANUAL_RANGE_CONTAINS),
-    LintId::of(ranges::RANGE_ZIP_WITH_LEN),
     LintId::of(ranges::REVERSED_EMPTY_RANGES),
     LintId::of(rc_clone_in_vec_init::RC_CLONE_IN_VEC_INIT),
     LintId::of(read_zero_byte_vec::READ_ZERO_BYTE_VEC),
@@ -286,7 +296,6 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(redundant_static_lifetimes::REDUNDANT_STATIC_LIFETIMES),
     LintId::of(reference::DEREF_ADDROF),
     LintId::of(regex::INVALID_REGEX),
-    LintId::of(repeat_once::REPEAT_ONCE),
     LintId::of(returns::LET_AND_RETURN),
     LintId::of(returns::NEEDLESS_RETURN),
     LintId::of(self_named_constructors::SELF_NAMED_CONSTRUCTORS),
@@ -314,10 +323,10 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(transmute::TRANSMUTE_INT_TO_FLOAT),
     LintId::of(transmute::TRANSMUTE_NUM_TO_BYTES),
     LintId::of(transmute::TRANSMUTE_PTR_TO_REF),
+    LintId::of(transmute::TRANSMUTING_NULL),
     LintId::of(transmute::UNSOUND_COLLECTION_TRANSMUTE),
     LintId::of(transmute::USELESS_TRANSMUTE),
     LintId::of(transmute::WRONG_TRANSMUTE),
-    LintId::of(transmuting_null::TRANSMUTING_NULL),
     LintId::of(types::BORROWED_BOX),
     LintId::of(types::BOX_COLLECTION),
     LintId::of(types::REDUNDANT_ALLOCATION),
@@ -325,7 +334,6 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(types::VEC_BOX),
     LintId::of(unicode::INVISIBLE_CHARACTERS),
     LintId::of(uninit_vec::UNINIT_VEC),
-    LintId::of(unit_hash::UNIT_HASH),
     LintId::of(unit_return_expecting_ord::UNIT_RETURN_EXPECTING_ORD),
     LintId::of(unit_types::LET_UNIT_VALUE),
     LintId::of(unit_types::UNIT_ARG),
@@ -333,9 +341,9 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(unnamed_address::FN_ADDRESS_COMPARISONS),
     LintId::of(unnamed_address::VTABLE_ADDRESS_COMPARISONS),
     LintId::of(unnecessary_owned_empty_strings::UNNECESSARY_OWNED_EMPTY_STRINGS),
-    LintId::of(unnecessary_sort_by::UNNECESSARY_SORT_BY),
     LintId::of(unsafe_removed_from_name::UNSAFE_REMOVED_FROM_NAME),
     LintId::of(unused_io_amount::UNUSED_IO_AMOUNT),
+    LintId::of(unused_peekable::UNUSED_PEEKABLE),
     LintId::of(unused_unit::UNUSED_UNIT),
     LintId::of(unwrap::PANICKING_UNWRAP),
     LintId::of(unwrap::UNNECESSARY_UNWRAP),
@@ -343,7 +351,7 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(useless_conversion::USELESS_CONVERSION),
     LintId::of(vec::USELESS_VEC),
     LintId::of(vec_init_then_push::VEC_INIT_THEN_PUSH),
-    LintId::of(vec_resize_to_zero::VEC_RESIZE_TO_ZERO),
+    LintId::of(write::POSITIONAL_NAMED_FORMAT_PARAMETERS),
     LintId::of(write::PRINTLN_EMPTY_STRING),
     LintId::of(write::PRINT_LITERAL),
     LintId::of(write::PRINT_WITH_NEWLINE),

src/tools/clippy/clippy_lints/src/lib.register_complexity.rs

@@ -6,7 +6,6 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(attrs::DEPRECATED_CFG_ATTR),
     LintId::of(booleans::NONMINIMAL_BOOL),
     LintId::of(borrow_deref_ref::BORROW_DEREF_REF),
-    LintId::of(bytes_count_to_len::BYTES_COUNT_TO_LEN),
     LintId::of(casts::CHAR_LIT_AS_U8),
     LintId::of(casts::UNNECESSARY_CAST),
     LintId::of(dereference::EXPLICIT_AUTO_DEREF),
@@ -33,6 +32,7 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(matches::NEEDLESS_MATCH),
     LintId::of(matches::WILDCARD_IN_OR_PATTERNS),
     LintId::of(methods::BIND_INSTEAD_OF_MAP),
+    LintId::of(methods::BYTES_COUNT_TO_LEN),
     LintId::of(methods::CLONE_ON_COPY),
     LintId::of(methods::FILTER_MAP_IDENTITY),
     LintId::of(methods::FILTER_NEXT),
@@ -51,10 +51,13 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(methods::OPTION_AS_REF_DEREF),
     LintId::of(methods::OPTION_FILTER_MAP),
     LintId::of(methods::OR_THEN_UNWRAP),
+    LintId::of(methods::RANGE_ZIP_WITH_LEN),
+    LintId::of(methods::REPEAT_ONCE),
     LintId::of(methods::SEARCH_IS_SOME),
     LintId::of(methods::SKIP_WHILE_NEXT),
     LintId::of(methods::UNNECESSARY_FILTER_MAP),
     LintId::of(methods::UNNECESSARY_FIND_MAP),
+    LintId::of(methods::UNNECESSARY_SORT_BY),
     LintId::of(methods::USELESS_ASREF),
     LintId::of(misc::SHORT_CIRCUIT_STATEMENT),
     LintId::of(misc_early::UNNEEDED_WILDCARD_PATTERN),
@@ -69,6 +72,7 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(neg_cmp_op_on_partial_ord::NEG_CMP_OP_ON_PARTIAL_ORD),
     LintId::of(no_effect::NO_EFFECT),
     LintId::of(no_effect::UNNECESSARY_OPERATION),
+    LintId::of(only_used_in_recursion::ONLY_USED_IN_RECURSION),
     LintId::of(operators::DOUBLE_COMPARISONS),
     LintId::of(operators::DURATION_SUBSEC),
     LintId::of(operators::IDENTITY_OP),
@@ -76,11 +80,9 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(partialeq_ne_impl::PARTIALEQ_NE_IMPL),
     LintId::of(precedence::PRECEDENCE),
     LintId::of(ptr_offset_with_cast::PTR_OFFSET_WITH_CAST),
-    LintId::of(ranges::RANGE_ZIP_WITH_LEN),
     LintId::of(redundant_closure_call::REDUNDANT_CLOSURE_CALL),
     LintId::of(redundant_slicing::REDUNDANT_SLICING),
     LintId::of(reference::DEREF_ADDROF),
-    LintId::of(repeat_once::REPEAT_ONCE),
     LintId::of(strings::STRING_FROM_UTF8_AS_BYTES),
     LintId::of(strlen_on_c_strings::STRLEN_ON_C_STRINGS),
     LintId::of(swap::MANUAL_SWAP),
@@ -99,7 +101,6 @@ store.register_group(true, "clippy::complexity", Some("clippy_complexity"), vec!
     LintId::of(types::TYPE_COMPLEXITY),
     LintId::of(types::VEC_BOX),
     LintId::of(unit_types::UNIT_ARG),
-    LintId::of(unnecessary_sort_by::UNNECESSARY_SORT_BY),
     LintId::of(unwrap::UNNECESSARY_UNWRAP),
     LintId::of(useless_conversion::USELESS_CONVERSION),
     LintId::of(zero_div_zero::ZERO_DIVIDED_BY_ZERO),

src/tools/clippy/clippy_lints/src/lib.register_correctness.rs

@@ -39,12 +39,14 @@ store.register_group(true, "clippy::correctness", Some("clippy_correctness"), ve
     LintId::of(mem_replace::MEM_REPLACE_WITH_UNINIT),
     LintId::of(methods::CLONE_DOUBLE_REF),
     LintId::of(methods::ITERATOR_STEP_BY_ZERO),
+    LintId::of(methods::NONSENSICAL_OPEN_OPTIONS),
     LintId::of(methods::SUSPICIOUS_SPLITN),
     LintId::of(methods::UNINIT_ASSUMED_INIT),
+    LintId::of(methods::UNIT_HASH),
+    LintId::of(methods::VEC_RESIZE_TO_ZERO),
     LintId::of(methods::ZST_OFFSET),
     LintId::of(minmax::MIN_MAX),
     LintId::of(non_octal_unix_permissions::NON_OCTAL_UNIX_PERMISSIONS),
-    LintId::of(open_options::NONSENSICAL_OPEN_OPTIONS),
     LintId::of(operators::ABSURD_EXTREME_COMPARISONS),
     LintId::of(operators::BAD_BIT_MASK),
     LintId::of(operators::CMP_NAN),
@@ -62,17 +64,15 @@ store.register_group(true, "clippy::correctness", Some("clippy_correctness"), ve
     LintId::of(serde_api::SERDE_API_MISUSE),
     LintId::of(size_of_in_element_count::SIZE_OF_IN_ELEMENT_COUNT),
     LintId::of(swap::ALMOST_SWAPPED),
+    LintId::of(transmute::TRANSMUTING_NULL),
     LintId::of(transmute::UNSOUND_COLLECTION_TRANSMUTE),
     LintId::of(transmute::WRONG_TRANSMUTE),
-    LintId::of(transmuting_null::TRANSMUTING_NULL),
     LintId::of(unicode::INVISIBLE_CHARACTERS),
     LintId::of(uninit_vec::UNINIT_VEC),
-    LintId::of(unit_hash::UNIT_HASH),
     LintId::of(unit_return_expecting_ord::UNIT_RETURN_EXPECTING_ORD),
     LintId::of(unit_types::UNIT_CMP),
     LintId::of(unnamed_address::FN_ADDRESS_COMPARISONS),
     LintId::of(unnamed_address::VTABLE_ADDRESS_COMPARISONS),
     LintId::of(unused_io_amount::UNUSED_IO_AMOUNT),
     LintId::of(unwrap::PANICKING_UNWRAP),
-    LintId::of(vec_resize_to_zero::VEC_RESIZE_TO_ZERO),
 ])

src/tools/clippy/clippy_lints/src/lib.register_lints.rs

@@ -38,7 +38,6 @@ store.register_lints(&[
     almost_complete_letter_range::ALMOST_COMPLETE_LETTER_RANGE,
     approx_const::APPROX_CONSTANT,
     as_conversions::AS_CONVERSIONS,
-    as_underscore::AS_UNDERSCORE,
     asm_syntax::INLINE_ASM_X86_ATT_SYNTAX,
     asm_syntax::INLINE_ASM_X86_INTEL_SYNTAX,
     assertions_on_constants::ASSERTIONS_ON_CONSTANTS,
@@ -59,16 +58,14 @@ store.register_lints(&[
     bool_assert_comparison::BOOL_ASSERT_COMPARISON,
     booleans::NONMINIMAL_BOOL,
     booleans::OVERLY_COMPLEX_BOOL_EXPR,
-    borrow_as_ptr::BORROW_AS_PTR,
     borrow_deref_ref::BORROW_DEREF_REF,
-    bytecount::NAIVE_BYTECOUNT,
-    bytes_count_to_len::BYTES_COUNT_TO_LEN,
     cargo::CARGO_COMMON_METADATA,
     cargo::MULTIPLE_CRATE_VERSIONS,
     cargo::NEGATIVE_FEATURE_NAMES,
     cargo::REDUNDANT_FEATURE_NAMES,
     cargo::WILDCARD_DEPENDENCIES,
-    case_sensitive_file_extension_comparisons::CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS,
+    casts::AS_UNDERSCORE,
+    casts::BORROW_AS_PTR,
     casts::CAST_ABS_TO_UNSIGNED,
     casts::CAST_ENUM_CONSTRUCTOR,
     casts::CAST_ENUM_TRUNCATION,
@@ -80,6 +77,7 @@ store.register_lints(&[
     casts::CAST_REF_TO_MUT,
     casts::CAST_SIGN_LOSS,
     casts::CAST_SLICE_DIFFERENT_SIZES,
+    casts::CAST_SLICE_FROM_RAW_PARTS,
     casts::CHAR_LIT_AS_U8,
     casts::FN_TO_NUMERIC_CAST,
     casts::FN_TO_NUMERIC_CAST_ANY,
@@ -173,11 +171,11 @@ store.register_lints(&[
     functions::MUST_USE_CANDIDATE,
     functions::MUST_USE_UNIT,
     functions::NOT_UNSAFE_PTR_ARG_DEREF,
+    functions::RESULT_LARGE_ERR,
     functions::RESULT_UNIT_ERR,
     functions::TOO_MANY_ARGUMENTS,
     functions::TOO_MANY_LINES,
     future_not_send::FUTURE_NOT_SEND,
-    get_first::GET_FIRST,
     if_let_mutex::IF_LET_MUTEX,
     if_not_else::IF_NOT_ELSE,
     if_then_some_else_none::IF_THEN_SOME_ELSE_NONE,
@@ -246,12 +244,10 @@ store.register_lints(&[
     manual_bits::MANUAL_BITS,
     manual_instant_elapsed::MANUAL_INSTANT_ELAPSED,
     manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE,
-    manual_ok_or::MANUAL_OK_OR,
     manual_rem_euclid::MANUAL_REM_EUCLID,
     manual_retain::MANUAL_RETAIN,
+    manual_string_new::MANUAL_STRING_NEW,
     manual_strip::MANUAL_STRIP,
-    map_clone::MAP_CLONE,
-    map_err_ignore::MAP_ERR_IGNORE,
     map_unit_fn::OPTION_MAP_UNIT_FN,
     map_unit_fn::RESULT_MAP_UNIT_FN,
     match_result_ok::MATCH_RESULT_OK,
@@ -284,13 +280,16 @@ store.register_lints(&[
     mem_replace::MEM_REPLACE_WITH_DEFAULT,
     mem_replace::MEM_REPLACE_WITH_UNINIT,
     methods::BIND_INSTEAD_OF_MAP,
+    methods::BYTES_COUNT_TO_LEN,
     methods::BYTES_NTH,
+    methods::CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS,
     methods::CHARS_LAST_CMP,
     methods::CHARS_NEXT_CMP,
     methods::CLONED_INSTEAD_OF_COPIED,
     methods::CLONE_DOUBLE_REF,
     methods::CLONE_ON_COPY,
     methods::CLONE_ON_REF_PTR,
+    methods::COLLAPSIBLE_STR_REPLACE,
     methods::ERR_EXPECT,
     methods::EXPECT_FUN_CALL,
     methods::EXPECT_USED,
@@ -302,6 +301,7 @@ store.register_lints(&[
     methods::FLAT_MAP_IDENTITY,
     methods::FLAT_MAP_OPTION,
     methods::FROM_ITER_INSTEAD_OF_COLLECT,
+    methods::GET_FIRST,
     methods::GET_LAST_WITH_LEN,
     methods::GET_UNWRAP,
     methods::IMPLICIT_CLONE,
@@ -315,22 +315,30 @@ store.register_lints(&[
     methods::ITER_NEXT_SLICE,
     methods::ITER_NTH,
     methods::ITER_NTH_ZERO,
+    methods::ITER_ON_EMPTY_COLLECTIONS,
+    methods::ITER_ON_SINGLE_ITEMS,
     methods::ITER_OVEREAGER_CLONED,
     methods::ITER_SKIP_NEXT,
     methods::ITER_WITH_DRAIN,
     methods::MANUAL_FILTER_MAP,
     methods::MANUAL_FIND_MAP,
+    methods::MANUAL_OK_OR,
     methods::MANUAL_SATURATING_ARITHMETIC,
     methods::MANUAL_SPLIT_ONCE,
     methods::MANUAL_STR_REPEAT,
+    methods::MAP_CLONE,
     methods::MAP_COLLECT_RESULT_UNIT,
+    methods::MAP_ERR_IGNORE,
     methods::MAP_FLATTEN,
     methods::MAP_IDENTITY,
     methods::MAP_UNWRAP_OR,
+    methods::MUT_MUTEX_LOCK,
+    methods::NAIVE_BYTECOUNT,
     methods::NEEDLESS_OPTION_AS_DEREF,
     methods::NEEDLESS_OPTION_TAKE,
     methods::NEEDLESS_SPLITN,
     methods::NEW_RET_NO_SELF,
+    methods::NONSENSICAL_OPEN_OPTIONS,
     methods::NO_EFFECT_REPLACE,
     methods::OBFUSCATED_IF_ELSE,
     methods::OK_EXPECT,
@@ -339,25 +347,34 @@ store.register_lints(&[
     methods::OPTION_MAP_OR_NONE,
     methods::OR_FUN_CALL,
     methods::OR_THEN_UNWRAP,
+    methods::PATH_BUF_PUSH_OVERWRITE,
+    methods::RANGE_ZIP_WITH_LEN,
+    methods::REPEAT_ONCE,
     methods::RESULT_MAP_OR_INTO_OPTION,
     methods::SEARCH_IS_SOME,
     methods::SHOULD_IMPLEMENT_TRAIT,
     methods::SINGLE_CHAR_ADD_STR,
     methods::SINGLE_CHAR_PATTERN,
     methods::SKIP_WHILE_NEXT,
+    methods::STABLE_SORT_PRIMITIVE,
     methods::STRING_EXTEND_CHARS,
     methods::SUSPICIOUS_MAP,
     methods::SUSPICIOUS_SPLITN,
+    methods::SUSPICIOUS_TO_OWNED,
     methods::UNINIT_ASSUMED_INIT,
+    methods::UNIT_HASH,
     methods::UNNECESSARY_FILTER_MAP,
     methods::UNNECESSARY_FIND_MAP,
     methods::UNNECESSARY_FOLD,
     methods::UNNECESSARY_JOIN,
     methods::UNNECESSARY_LAZY_EVALUATIONS,
+    methods::UNNECESSARY_SORT_BY,
     methods::UNNECESSARY_TO_OWNED,
     methods::UNWRAP_OR_ELSE_DEFAULT,
     methods::UNWRAP_USED,
     methods::USELESS_ASREF,
+    methods::VEC_RESIZE_TO_ZERO,
+    methods::VERBOSE_FILE_READS,
     methods::WRONG_SELF_CONVENTION,
     methods::ZST_OFFSET,
     minmax::MIN_MAX,
@@ -384,9 +401,9 @@ store.register_lints(&[
     mixed_read_write_in_expression::MIXED_READ_WRITE_IN_EXPRESSION,
     module_style::MOD_MODULE_FILES,
     module_style::SELF_NAMED_MODULE_FILES,
+    multi_assignments::MULTI_ASSIGNMENTS,
     mut_key::MUTABLE_KEY_TYPE,
     mut_mut::MUT_MUT,
-    mut_mutex_lock::MUT_MUTEX_LOCK,
     mut_reference::UNNECESSARY_MUT_PASSED,
     mutable_debug_assertion::DEBUG_ASSERT_WITH_MUT_CALL,
     mutex_atomic::MUTEX_ATOMIC,
@@ -418,7 +435,6 @@ store.register_lints(&[
     nonstandard_macro_braces::NONSTANDARD_MACRO_BRACES,
     octal_escapes::OCTAL_ESCAPES,
     only_used_in_recursion::ONLY_USED_IN_RECURSION,
-    open_options::NONSENSICAL_OPEN_OPTIONS,
     operators::ABSURD_EXTREME_COMPARISONS,
     operators::ARITHMETIC,
     operators::ASSIGN_OP_PATTERN,
@@ -457,7 +473,6 @@ store.register_lints(&[
     partialeq_to_none::PARTIALEQ_TO_NONE,
     pass_by_ref_or_value::LARGE_TYPES_PASSED_BY_VALUE,
     pass_by_ref_or_value::TRIVIALLY_COPY_PASS_BY_REF,
-    path_buf_push_overwrite::PATH_BUF_PUSH_OVERWRITE,
     pattern_type_mismatch::PATTERN_TYPE_MISMATCH,
     precedence::PRECEDENCE,
     ptr::CMP_NULL,
@@ -470,7 +485,6 @@ store.register_lints(&[
     ranges::MANUAL_RANGE_CONTAINS,
     ranges::RANGE_MINUS_ONE,
     ranges::RANGE_PLUS_ONE,
-    ranges::RANGE_ZIP_WITH_LEN,
     ranges::REVERSED_EMPTY_RANGES,
     rc_clone_in_vec_init::RC_CLONE_IN_VEC_INIT,
     read_zero_byte_vec::READ_ZERO_BYTE_VEC,
@@ -486,7 +500,6 @@ store.register_lints(&[
     reference::DEREF_ADDROF,
     regex::INVALID_REGEX,
     regex::TRIVIAL_REGEX,
-    repeat_once::REPEAT_ONCE,
     return_self_not_must_use::RETURN_SELF_NOT_MUST_USE,
     returns::LET_AND_RETURN,
     returns::NEEDLESS_RETURN,
@@ -501,7 +514,6 @@ store.register_lints(&[
     single_component_path_imports::SINGLE_COMPONENT_PATH_IMPORTS,
     size_of_in_element_count::SIZE_OF_IN_ELEMENT_COUNT,
     slow_vector_initialization::SLOW_VECTOR_INITIALIZATION,
-    stable_sort_primitive::STABLE_SORT_PRIMITIVE,
     std_instead_of_core::ALLOC_INSTEAD_OF_CORE,
     std_instead_of_core::STD_INSTEAD_OF_ALLOC,
     std_instead_of_core::STD_INSTEAD_OF_CORE,
@@ -537,10 +549,10 @@ store.register_lints(&[
     transmute::TRANSMUTE_PTR_TO_PTR,
     transmute::TRANSMUTE_PTR_TO_REF,
     transmute::TRANSMUTE_UNDEFINED_REPR,
+    transmute::TRANSMUTING_NULL,
     transmute::UNSOUND_COLLECTION_TRANSMUTE,
     transmute::USELESS_TRANSMUTE,
     transmute::WRONG_TRANSMUTE,
-    transmuting_null::TRANSMUTING_NULL,
     types::BORROWED_BOX,
     types::BOX_COLLECTION,
     types::LINKEDLIST,
@@ -555,7 +567,6 @@ store.register_lints(&[
     unicode::NON_ASCII_LITERAL,
     unicode::UNICODE_NOT_NFC,
     uninit_vec::UNINIT_VEC,
-    unit_hash::UNIT_HASH,
     unit_return_expecting_ord::UNIT_RETURN_EXPECTING_ORD,
     unit_types::LET_UNIT_VALUE,
     unit_types::UNIT_ARG,
@@ -564,12 +575,12 @@ store.register_lints(&[
     unnamed_address::VTABLE_ADDRESS_COMPARISONS,
     unnecessary_owned_empty_strings::UNNECESSARY_OWNED_EMPTY_STRINGS,
     unnecessary_self_imports::UNNECESSARY_SELF_IMPORTS,
-    unnecessary_sort_by::UNNECESSARY_SORT_BY,
     unnecessary_wraps::UNNECESSARY_WRAPS,
     unnested_or_patterns::UNNESTED_OR_PATTERNS,
     unsafe_removed_from_name::UNSAFE_REMOVED_FROM_NAME,
     unused_async::UNUSED_ASYNC,
     unused_io_amount::UNUSED_IO_AMOUNT,
+    unused_peekable::UNUSED_PEEKABLE,
     unused_rounding::UNUSED_ROUNDING,
     unused_self::UNUSED_SELF,
     unused_unit::UNUSED_UNIT,
@@ -581,10 +592,9 @@ store.register_lints(&[
     useless_conversion::USELESS_CONVERSION,
     vec::USELESS_VEC,
     vec_init_then_push::VEC_INIT_THEN_PUSH,
-    vec_resize_to_zero::VEC_RESIZE_TO_ZERO,
-    verbose_file_reads::VERBOSE_FILE_READS,
     wildcard_imports::ENUM_GLOB_USE,
     wildcard_imports::WILDCARD_IMPORTS,
+    write::POSITIONAL_NAMED_FORMAT_PARAMETERS,
     write::PRINTLN_EMPTY_STRING,
     write::PRINT_LITERAL,
     write::PRINT_STDERR,

src/tools/clippy/clippy_lints/src/lib.register_nursery.rs

@@ -14,16 +14,17 @@ store.register_group(true, "clippy::nursery", Some("clippy_nursery"), vec![
     LintId::of(index_refutable_slice::INDEX_REFUTABLE_SLICE),
     LintId::of(let_if_seq::USELESS_LET_IF_SEQ),
     LintId::of(matches::SIGNIFICANT_DROP_IN_SCRUTINEE),
+    LintId::of(methods::ITER_ON_EMPTY_COLLECTIONS),
+    LintId::of(methods::ITER_ON_SINGLE_ITEMS),
     LintId::of(methods::ITER_WITH_DRAIN),
+    LintId::of(methods::PATH_BUF_PUSH_OVERWRITE),
     LintId::of(missing_const_for_fn::MISSING_CONST_FOR_FN),
     LintId::of(mutable_debug_assertion::DEBUG_ASSERT_WITH_MUT_CALL),
     LintId::of(mutex_atomic::MUTEX_ATOMIC),
     LintId::of(mutex_atomic::MUTEX_INTEGER),
     LintId::of(non_send_fields_in_send_ty::NON_SEND_FIELDS_IN_SEND_TY),
     LintId::of(nonstandard_macro_braces::NONSTANDARD_MACRO_BRACES),
-    LintId::of(only_used_in_recursion::ONLY_USED_IN_RECURSION),
     LintId::of(option_if_let_else::OPTION_IF_LET_ELSE),
-    LintId::of(path_buf_push_overwrite::PATH_BUF_PUSH_OVERWRITE),
     LintId::of(redundant_pub_crate::REDUNDANT_PUB_CRATE),
     LintId::of(regex::TRIVIAL_REGEX),
     LintId::of(strings::STRING_LIT_AS_BYTES),

src/tools/clippy/clippy_lints/src/lib.register_pedantic.rs

@@ -4,9 +4,7 @@
 
 store.register_group(true, "clippy::pedantic", Some("clippy_pedantic"), vec![
     LintId::of(attrs::INLINE_ALWAYS),
-    LintId::of(borrow_as_ptr::BORROW_AS_PTR),
+    LintId::of(casts::BORROW_AS_PTR),
-    LintId::of(bytecount::NAIVE_BYTECOUNT),
-    LintId::of(case_sensitive_file_extension_comparisons::CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS),
     LintId::of(casts::CAST_LOSSLESS),
     LintId::of(casts::CAST_POSSIBLE_TRUNCATION),
     LintId::of(casts::CAST_POSSIBLE_WRAP),
@@ -50,20 +48,24 @@ store.register_group(true, "clippy::pedantic", Some("clippy_pedantic"), vec![
     LintId::of(macro_use::MACRO_USE_IMPORTS),
     LintId::of(manual_assert::MANUAL_ASSERT),
     LintId::of(manual_instant_elapsed::MANUAL_INSTANT_ELAPSED),
-    LintId::of(manual_ok_or::MANUAL_OK_OR),
+    LintId::of(manual_string_new::MANUAL_STRING_NEW),
     LintId::of(matches::MATCH_BOOL),
     LintId::of(matches::MATCH_ON_VEC_ITEMS),
     LintId::of(matches::MATCH_SAME_ARMS),
     LintId::of(matches::MATCH_WILDCARD_FOR_SINGLE_VARIANTS),
     LintId::of(matches::MATCH_WILD_ERR_ARM),
     LintId::of(matches::SINGLE_MATCH_ELSE),
+    LintId::of(methods::CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS),
     LintId::of(methods::CLONED_INSTEAD_OF_COPIED),
     LintId::of(methods::FILTER_MAP_NEXT),
     LintId::of(methods::FLAT_MAP_OPTION),
     LintId::of(methods::FROM_ITER_INSTEAD_OF_COLLECT),
     LintId::of(methods::IMPLICIT_CLONE),
     LintId::of(methods::INEFFICIENT_TO_STRING),
+    LintId::of(methods::MANUAL_OK_OR),
     LintId::of(methods::MAP_UNWRAP_OR),
+    LintId::of(methods::NAIVE_BYTECOUNT),
+    LintId::of(methods::STABLE_SORT_PRIMITIVE),
     LintId::of(methods::UNNECESSARY_JOIN),
     LintId::of(misc::USED_UNDERSCORE_BINDING),
     LintId::of(mismatching_type_param_order::MISMATCHING_TYPE_PARAM_ORDER),
@@ -85,7 +87,6 @@ store.register_group(true, "clippy::pedantic", Some("clippy_pedantic"), vec![
     LintId::of(ref_option_ref::REF_OPTION_REF),
     LintId::of(return_self_not_must_use::RETURN_SELF_NOT_MUST_USE),
     LintId::of(semicolon_if_nothing_returned::SEMICOLON_IF_NOTHING_RETURNED),
-    LintId::of(stable_sort_primitive::STABLE_SORT_PRIMITIVE),
     LintId::of(strings::STRING_ADD_ASSIGN),
     LintId::of(trait_bounds::TRAIT_DUPLICATION_IN_BOUNDS),
     LintId::of(trait_bounds::TYPE_REPETITION_IN_BOUNDS),

src/tools/clippy/clippy_lints/src/lib.register_perf.rs

@@ -7,12 +7,14 @@ store.register_group(true, "clippy::perf", Some("clippy_perf"), vec![
     LintId::of(escape::BOXED_LOCAL),
     LintId::of(format_args::FORMAT_IN_FORMAT_ARGS),
     LintId::of(format_args::TO_STRING_IN_FORMAT_ARGS),
+    LintId::of(functions::RESULT_LARGE_ERR),
     LintId::of(large_const_arrays::LARGE_CONST_ARRAYS),
     LintId::of(large_enum_variant::LARGE_ENUM_VARIANT),
     LintId::of(loops::MANUAL_MEMCPY),
     LintId::of(loops::MISSING_SPIN_LOOP),
     LintId::of(loops::NEEDLESS_COLLECT),
     LintId::of(manual_retain::MANUAL_RETAIN),
+    LintId::of(methods::COLLAPSIBLE_STR_REPLACE),
     LintId::of(methods::EXPECT_FUN_CALL),
     LintId::of(methods::EXTEND_WITH_DRAIN),
     LintId::of(methods::ITER_NTH),

src/tools/clippy/clippy_lints/src/lib.register_restriction.rs

@@ -4,11 +4,11 @@
 
 store.register_group(true, "clippy::restriction", Some("clippy_restriction"), vec![
     LintId::of(as_conversions::AS_CONVERSIONS),
-    LintId::of(as_underscore::AS_UNDERSCORE),
     LintId::of(asm_syntax::INLINE_ASM_X86_ATT_SYNTAX),
     LintId::of(asm_syntax::INLINE_ASM_X86_INTEL_SYNTAX),
     LintId::of(assertions_on_result_states::ASSERTIONS_ON_RESULT_STATES),
     LintId::of(attrs::ALLOW_ATTRIBUTES_WITHOUT_REASON),
+    LintId::of(casts::AS_UNDERSCORE),
     LintId::of(casts::FN_TO_NUMERIC_CAST_ANY),
     LintId::of(create_dir::CREATE_DIR),
     LintId::of(dbg_macro::DBG_MACRO),
@@ -30,7 +30,6 @@ store.register_group(true, "clippy::restriction", Some("clippy_restriction"), ve
     LintId::of(large_include_file::LARGE_INCLUDE_FILE),
     LintId::of(let_underscore::LET_UNDERSCORE_MUST_USE),
     LintId::of(literal_representation::DECIMAL_LITERAL_REPRESENTATION),
-    LintId::of(map_err_ignore::MAP_ERR_IGNORE),
     LintId::of(matches::REST_PAT_IN_FULLY_BOUND_STRUCTS),
     LintId::of(matches::TRY_ERR),
     LintId::of(matches::WILDCARD_ENUM_MATCH_ARM),
@@ -39,7 +38,9 @@ store.register_group(true, "clippy::restriction", Some("clippy_restriction"), ve
     LintId::of(methods::EXPECT_USED),
     LintId::of(methods::FILETYPE_IS_FILE),
     LintId::of(methods::GET_UNWRAP),
+    LintId::of(methods::MAP_ERR_IGNORE),
     LintId::of(methods::UNWRAP_USED),
+    LintId::of(methods::VERBOSE_FILE_READS),
     LintId::of(misc_early::SEPARATED_LITERAL_SUFFIX),
     LintId::of(misc_early::UNNEEDED_FIELD_PATTERN),
     LintId::of(misc_early::UNSEPARATED_LITERAL_SUFFIX),
@@ -81,7 +82,6 @@ store.register_group(true, "clippy::restriction", Some("clippy_restriction"), ve
     LintId::of(unicode::NON_ASCII_LITERAL),
     LintId::of(unnecessary_self_imports::UNNECESSARY_SELF_IMPORTS),
     LintId::of(unwrap_in_result::UNWRAP_IN_RESULT),
-    LintId::of(verbose_file_reads::VERBOSE_FILE_READS),
     LintId::of(write::PRINT_STDERR),
     LintId::of(write::PRINT_STDOUT),
     LintId::of(write::USE_DEBUG),

src/tools/clippy/clippy_lints/src/lib.register_style.rs

@@ -29,7 +29,6 @@ store.register_group(true, "clippy::style", Some("clippy_style"), vec![
     LintId::of(functions::DOUBLE_MUST_USE),
     LintId::of(functions::MUST_USE_UNIT),
     LintId::of(functions::RESULT_UNIT_ERR),
-    LintId::of(get_first::GET_FIRST),
     LintId::of(inherent_to_string::INHERENT_TO_STRING),
     LintId::of(init_numbered_fields::INIT_NUMBERED_FIELDS),
     LintId::of(len_zero::COMPARISON_TO_EMPTY),
@@ -45,7 +44,6 @@ store.register_group(true, "clippy::style", Some("clippy_style"), vec![
     LintId::of(manual_async_fn::MANUAL_ASYNC_FN),
     LintId::of(manual_bits::MANUAL_BITS),
     LintId::of(manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE),
-    LintId::of(map_clone::MAP_CLONE),
     LintId::of(match_result_ok::MATCH_RESULT_OK),
     LintId::of(matches::COLLAPSIBLE_MATCH),
     LintId::of(matches::INFALLIBLE_DESTRUCTURING_MATCH),
@@ -61,6 +59,7 @@ store.register_group(true, "clippy::style", Some("clippy_style"), vec![
     LintId::of(methods::CHARS_LAST_CMP),
     LintId::of(methods::CHARS_NEXT_CMP),
     LintId::of(methods::ERR_EXPECT),
+    LintId::of(methods::GET_FIRST),
     LintId::of(methods::INTO_ITER_ON_REF),
     LintId::of(methods::IS_DIGIT_ASCII_RADIX),
     LintId::of(methods::ITER_CLONED_COLLECT),
@@ -68,7 +67,9 @@ store.register_group(true, "clippy::style", Some("clippy_style"), vec![
     LintId::of(methods::ITER_NTH_ZERO),
     LintId::of(methods::ITER_SKIP_NEXT),
     LintId::of(methods::MANUAL_SATURATING_ARITHMETIC),
+    LintId::of(methods::MAP_CLONE),
     LintId::of(methods::MAP_COLLECT_RESULT_UNIT),
+    LintId::of(methods::MUT_MUTEX_LOCK),
     LintId::of(methods::NEW_RET_NO_SELF),
     LintId::of(methods::OBFUSCATED_IF_ELSE),
     LintId::of(methods::OK_EXPECT),
@@ -88,7 +89,6 @@ store.register_group(true, "clippy::style", Some("clippy_style"), vec![
     LintId::of(misc_early::DUPLICATE_UNDERSCORE_ARGUMENT),
     LintId::of(misc_early::MIXED_CASE_HEX_LITERALS),
     LintId::of(misc_early::REDUNDANT_PATTERN),
-    LintId::of(mut_mutex_lock::MUT_MUTEX_LOCK),
     LintId::of(mut_reference::UNNECESSARY_MUT_PASSED),
     LintId::of(needless_late_init::NEEDLESS_LATE_INIT),
     LintId::of(needless_parens_on_range_literals::NEEDLESS_PARENS_ON_RANGE_LITERALS),

src/tools/clippy/clippy_lints/src/lib.register_suspicious.rs

@@ -11,6 +11,7 @@ store.register_group(true, "clippy::suspicious", Some("clippy_suspicious"), vec!
     LintId::of(casts::CAST_ABS_TO_UNSIGNED),
     LintId::of(casts::CAST_ENUM_CONSTRUCTOR),
     LintId::of(casts::CAST_ENUM_TRUNCATION),
+    LintId::of(casts::CAST_SLICE_FROM_RAW_PARTS),
     LintId::of(crate_in_macro_def::CRATE_IN_MACRO_DEF),
     LintId::of(drop_forget_ref::DROP_NON_DROP),
     LintId::of(drop_forget_ref::FORGET_NON_DROP),
@@ -24,6 +25,8 @@ store.register_group(true, "clippy::suspicious", Some("clippy_suspicious"), vec!
     LintId::of(loops::MUT_RANGE_BOUND),
     LintId::of(methods::NO_EFFECT_REPLACE),
     LintId::of(methods::SUSPICIOUS_MAP),
+    LintId::of(methods::SUSPICIOUS_TO_OWNED),
+    LintId::of(multi_assignments::MULTI_ASSIGNMENTS),
     LintId::of(mut_key::MUTABLE_KEY_TYPE),
     LintId::of(octal_escapes::OCTAL_ESCAPES),
     LintId::of(operators::FLOAT_EQUALITY_WITHOUT_ABS),
@@ -32,4 +35,6 @@ store.register_group(true, "clippy::suspicious", Some("clippy_suspicious"), vec!
     LintId::of(suspicious_trait_impl::SUSPICIOUS_ARITHMETIC_IMPL),
     LintId::of(suspicious_trait_impl::SUSPICIOUS_OP_ASSIGN_IMPL),
     LintId::of(swap_ptr_to_ref::SWAP_PTR_TO_REF),
+    LintId::of(unused_peekable::UNUSED_PEEKABLE),
+    LintId::of(write::POSITIONAL_NAMED_FORMAT_PARAMETERS),
 ])

src/tools/clippy/clippy_lints/src/lib.rs

@@ -171,7 +171,6 @@ mod renamed_lints;
 mod almost_complete_letter_range;
 mod approx_const;
 mod as_conversions;
-mod as_underscore;
 mod asm_syntax;
 mod assertions_on_constants;
 mod assertions_on_result_states;
@@ -181,12 +180,8 @@ mod await_holding_invalid;
 mod blocks_in_if_conditions;
 mod bool_assert_comparison;
 mod booleans;
-mod borrow_as_ptr;
 mod borrow_deref_ref;
-mod bytecount;
-mod bytes_count_to_len;
 mod cargo;
-mod case_sensitive_file_extension_comparisons;
 mod casts;
 mod checked_conversions;
 mod cognitive_complexity;
@@ -239,7 +234,6 @@ mod from_over_into;
 mod from_str_radix_10;
 mod functions;
 mod future_not_send;
-mod get_first;
 mod if_let_mutex;
 mod if_not_else;
 mod if_then_some_else_none;
@@ -276,12 +270,10 @@ mod manual_async_fn;
 mod manual_bits;
 mod manual_instant_elapsed;
 mod manual_non_exhaustive;
-mod manual_ok_or;
 mod manual_rem_euclid;
 mod manual_retain;
+mod manual_string_new;
 mod manual_strip;
-mod map_clone;
-mod map_err_ignore;
 mod map_unit_fn;
 mod match_result_ok;
 mod matches;
@@ -298,9 +290,9 @@ mod missing_enforced_import_rename;
 mod missing_inline;
 mod mixed_read_write_in_expression;
 mod module_style;
+mod multi_assignments;
 mod mut_key;
 mod mut_mut;
-mod mut_mutex_lock;
 mod mut_reference;
 mod mutable_debug_assertion;
 mod mutex_atomic;
@@ -325,7 +317,6 @@ mod non_send_fields_in_send_ty;
 mod nonstandard_macro_braces;
 mod octal_escapes;
 mod only_used_in_recursion;
-mod open_options;
 mod operators;
 mod option_env_unwrap;
 mod option_if_let_else;
@@ -335,7 +326,6 @@ mod panic_unimplemented;
 mod partialeq_ne_impl;
 mod partialeq_to_none;
 mod pass_by_ref_or_value;
-mod path_buf_push_overwrite;
 mod pattern_type_mismatch;
 mod precedence;
 mod ptr;
@@ -355,7 +345,6 @@ mod redundant_static_lifetimes;
 mod ref_option_ref;
 mod reference;
 mod regex;
-mod repeat_once;
 mod return_self_not_must_use;
 mod returns;
 mod same_name_method;
@@ -367,7 +356,6 @@ mod single_char_lifetime_names;
 mod single_component_path_imports;
 mod size_of_in_element_count;
 mod slow_vector_initialization;
-mod stable_sort_primitive;
 mod std_instead_of_core;
 mod strings;
 mod strlen_on_c_strings;
@@ -381,23 +369,21 @@ mod to_digit_is_some;
 mod trailing_empty_array;
 mod trait_bounds;
 mod transmute;
-mod transmuting_null;
 mod types;
 mod undocumented_unsafe_blocks;
 mod unicode;
 mod uninit_vec;
-mod unit_hash;
 mod unit_return_expecting_ord;
 mod unit_types;
 mod unnamed_address;
 mod unnecessary_owned_empty_strings;
 mod unnecessary_self_imports;
-mod unnecessary_sort_by;
 mod unnecessary_wraps;
 mod unnested_or_patterns;
 mod unsafe_removed_from_name;
 mod unused_async;
 mod unused_io_amount;
+mod unused_peekable;
 mod unused_rounding;
 mod unused_self;
 mod unused_unit;
@@ -408,8 +394,6 @@ mod use_self;
 mod useless_conversion;
 mod vec;
 mod vec_init_then_push;
-mod vec_resize_to_zero;
-mod verbose_file_reads;
 mod wildcard_imports;
 mod write;
 mod zero_div_zero;
@@ -597,7 +581,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(blocks_in_if_conditions::BlocksInIfConditions));
     store.register_late_pass(|| Box::new(unicode::Unicode));
     store.register_late_pass(|| Box::new(uninit_vec::UninitVec));
-    store.register_late_pass(|| Box::new(unit_hash::UnitHash));
     store.register_late_pass(|| Box::new(unit_return_expecting_ord::UnitReturnExpectingOrd));
     store.register_late_pass(|| Box::new(strings::StringAdd));
     store.register_late_pass(|| Box::new(implicit_return::ImplicitReturn));
@@ -635,8 +618,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(move || Box::new(needless_question_mark::NeedlessQuestionMark));
     store.register_late_pass(move || Box::new(casts::Casts::new(msrv)));
     store.register_early_pass(move || Box::new(unnested_or_patterns::UnnestedOrPatterns::new(msrv)));
-    store.register_late_pass(move || Box::new(map_clone::MapClone::new(msrv)));
-
     store.register_late_pass(|| Box::new(size_of_in_element_count::SizeOfInElementCount));
     store.register_late_pass(|| Box::new(same_name_method::SameNameMethod));
     let max_suggested_slice_pattern_length = conf.max_suggested_slice_pattern_length;
@@ -646,7 +627,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
             msrv,
         ))
     });
-    store.register_late_pass(|| Box::new(map_err_ignore::MapErrIgnore));
     store.register_late_pass(|| Box::new(shadow::Shadow::default()));
     store.register_late_pass(|| Box::new(unit_types::UnitTypes));
     store.register_late_pass(|| Box::new(loops::Loops));
@@ -654,7 +634,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(lifetimes::Lifetimes));
     store.register_late_pass(|| Box::new(entry::HashMapPass));
     store.register_late_pass(|| Box::new(minmax::MinMaxPass));
-    store.register_late_pass(|| Box::new(open_options::OpenOptions));
     store.register_late_pass(|| Box::new(zero_div_zero::ZeroDiv));
     store.register_late_pass(|| Box::new(mutex_atomic::Mutex));
     store.register_late_pass(|| Box::new(needless_update::NeedlessUpdate));
@@ -690,10 +669,12 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(move || Box::new(disallowed_names::DisallowedNames::new(disallowed_names.clone())));
     let too_many_arguments_threshold = conf.too_many_arguments_threshold;
     let too_many_lines_threshold = conf.too_many_lines_threshold;
+    let large_error_threshold = conf.large_error_threshold;
     store.register_late_pass(move || {
         Box::new(functions::Functions::new(
             too_many_arguments_threshold,
             too_many_lines_threshold,
+            large_error_threshold,
         ))
     });
     let doc_valid_idents = conf.doc_valid_idents.iter().cloned().collect::<FxHashSet<_>>();
@@ -720,7 +701,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     );
     store.register_late_pass(move || Box::new(pass_by_ref_or_value));
     store.register_late_pass(|| Box::new(ref_option_ref::RefOptionRef));
-    store.register_late_pass(|| Box::new(bytecount::ByteCount));
     store.register_late_pass(|| Box::new(infinite_iter::InfiniteIter));
     store.register_late_pass(|| Box::new(inline_fn_without_body::InlineFnWithoutBody));
     store.register_late_pass(|| Box::new(useless_conversion::UselessConversion::default()));
@@ -738,12 +718,9 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(ptr_offset_with_cast::PtrOffsetWithCast));
     store.register_late_pass(|| Box::new(redundant_clone::RedundantClone));
     store.register_late_pass(|| Box::new(slow_vector_initialization::SlowVectorInit));
-    store.register_late_pass(|| Box::new(unnecessary_sort_by::UnnecessarySortBy));
     store.register_late_pass(move || Box::new(unnecessary_wraps::UnnecessaryWraps::new(avoid_breaking_exported_api)));
     store.register_late_pass(|| Box::new(assertions_on_constants::AssertionsOnConstants));
     store.register_late_pass(|| Box::new(assertions_on_result_states::AssertionsOnResultStates));
-    store.register_late_pass(|| Box::new(transmuting_null::TransmutingNull));
-    store.register_late_pass(|| Box::new(path_buf_push_overwrite::PathBufPushOverwrite));
     store.register_late_pass(|| Box::new(inherent_to_string::InherentToString));
     let max_trait_bounds = conf.max_trait_bounds;
     store.register_late_pass(move || Box::new(trait_bounds::TraitBounds::new(max_trait_bounds)));
@@ -819,18 +796,15 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_early_pass(|| Box::new(option_env_unwrap::OptionEnvUnwrap));
     let warn_on_all_wildcard_imports = conf.warn_on_all_wildcard_imports;
     store.register_late_pass(move || Box::new(wildcard_imports::WildcardImports::new(warn_on_all_wildcard_imports)));
-    store.register_late_pass(|| Box::new(verbose_file_reads::VerboseFileReads));
     store.register_late_pass(|| Box::new(redundant_pub_crate::RedundantPubCrate::default()));
     store.register_late_pass(|| Box::new(unnamed_address::UnnamedAddress));
-    store.register_late_pass(|| Box::new(dereference::Dereferencing::default()));
+    store.register_late_pass(move || Box::new(dereference::Dereferencing::new(msrv)));
     store.register_late_pass(|| Box::new(option_if_let_else::OptionIfLetElse));
     store.register_late_pass(|| Box::new(future_not_send::FutureNotSend));
     store.register_late_pass(|| Box::new(if_let_mutex::IfLetMutex));
     store.register_late_pass(|| Box::new(if_not_else::IfNotElse));
     store.register_late_pass(|| Box::new(equatable_if_let::PatternEquality));
-    store.register_late_pass(|| Box::new(mut_mutex_lock::MutMutexLock));
     store.register_late_pass(|| Box::new(manual_async_fn::ManualAsyncFn));
-    store.register_late_pass(|| Box::new(vec_resize_to_zero::VecResizeToZero));
     store.register_late_pass(|| Box::new(panic_in_result_fn::PanicInResultFn));
     let single_char_binding_names_threshold = conf.single_char_binding_names_threshold;
     store.register_early_pass(move || {
@@ -842,10 +816,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_early_pass(move || Box::new(nonstandard_macro_braces::MacroBraces::new(&macro_matcher)));
     store.register_late_pass(|| Box::new(macro_use::MacroUseImports::default()));
     store.register_late_pass(|| Box::new(pattern_type_mismatch::PatternTypeMismatch));
-    store.register_late_pass(|| Box::new(stable_sort_primitive::StableSortPrimitive));
-    store.register_late_pass(|| Box::new(repeat_once::RepeatOnce));
     store.register_late_pass(|| Box::new(unwrap_in_result::UnwrapInResult));
-    store.register_late_pass(|| Box::new(manual_ok_or::ManualOkOr));
     store.register_late_pass(|| Box::new(semicolon_if_nothing_returned::SemicolonIfNothingReturned));
     store.register_late_pass(|| Box::new(async_yields_async::AsyncYieldsAsync));
     let disallowed_methods = conf.disallowed_methods.clone();
@@ -857,9 +828,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(strings::StringToString));
     store.register_late_pass(|| Box::new(zero_sized_map_values::ZeroSizedMapValues));
     store.register_late_pass(|| Box::new(vec_init_then_push::VecInitThenPush::default()));
-    store.register_late_pass(|| {
-        Box::new(case_sensitive_file_extension_comparisons::CaseSensitiveFileExtensionComparisons)
-    });
     store.register_late_pass(|| Box::new(redundant_slicing::RedundantSlicing));
     store.register_late_pass(|| Box::new(from_str_radix_10::FromStrRadix10));
     store.register_late_pass(move || Box::new(if_then_some_else_none::IfThenSomeElseNone::new(msrv)));
@@ -894,11 +862,10 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(return_self_not_must_use::ReturnSelfNotMustUse));
     store.register_late_pass(|| Box::new(init_numbered_fields::NumberedFields));
     store.register_early_pass(|| Box::new(single_char_lifetime_names::SingleCharLifetimeNames));
-    store.register_late_pass(move || Box::new(borrow_as_ptr::BorrowAsPtr::new(msrv)));
     store.register_late_pass(move || Box::new(manual_bits::ManualBits::new(msrv)));
     store.register_late_pass(|| Box::new(default_union_representation::DefaultUnionRepresentation));
     store.register_early_pass(|| Box::new(doc_link_with_quotes::DocLinkWithQuotes));
-    store.register_late_pass(|| Box::new(only_used_in_recursion::OnlyUsedInRecursion));
+    store.register_late_pass(|| Box::new(only_used_in_recursion::OnlyUsedInRecursion::default()));
     let allow_dbg_in_tests = conf.allow_dbg_in_tests;
     store.register_late_pass(move || Box::new(dbg_macro::DbgMacro::new(allow_dbg_in_tests)));
     let cargo_ignore_publish = conf.cargo_ignore_publish;
@@ -912,18 +879,15 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(unnecessary_owned_empty_strings::UnnecessaryOwnedEmptyStrings));
     store.register_early_pass(|| Box::new(pub_use::PubUse));
     store.register_late_pass(|| Box::new(format_push_string::FormatPushString));
-    store.register_late_pass(|| Box::new(bytes_count_to_len::BytesCountToLen));
     let max_include_file_size = conf.max_include_file_size;
     store.register_late_pass(move || Box::new(large_include_file::LargeIncludeFile::new(max_include_file_size)));
     store.register_late_pass(|| Box::new(strings::TrimSplitWhitespace));
     store.register_late_pass(|| Box::new(rc_clone_in_vec_init::RcCloneInVecInit));
     store.register_early_pass(|| Box::new(duplicate_mod::DuplicateMod::default()));
-    store.register_late_pass(|| Box::new(get_first::GetFirst));
     store.register_early_pass(|| Box::new(unused_rounding::UnusedRounding));
     store.register_early_pass(move || Box::new(almost_complete_letter_range::AlmostCompleteLetterRange::new(msrv)));
     store.register_late_pass(|| Box::new(swap_ptr_to_ref::SwapPtrToRef));
     store.register_late_pass(|| Box::new(mismatching_type_param_order::TypeParamMismatch));
-    store.register_late_pass(|| Box::new(as_underscore::AsUnderscore));
     store.register_late_pass(|| Box::new(read_zero_byte_vec::ReadZeroByteVec));
     store.register_late_pass(|| Box::new(default_instead_of_iter_empty::DefaultIterEmpty));
     store.register_late_pass(move || Box::new(manual_rem_euclid::ManualRemEuclid::new(msrv)));
@@ -934,6 +898,9 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(std_instead_of_core::StdReexports::default()));
     store.register_late_pass(|| Box::new(manual_instant_elapsed::ManualInstantElapsed));
     store.register_late_pass(|| Box::new(partialeq_to_none::PartialeqToNone));
+    store.register_late_pass(|| Box::new(manual_string_new::ManualStringNew));
+    store.register_late_pass(|| Box::new(unused_peekable::UnusedPeekable));
+    store.register_early_pass(|| Box::new(multi_assignments::MultiAssignments));
     // add lints here, do not remove this comment, it's used in `new_lint`
 }
 

src/tools/clippy/clippy_lints/src/loops/needless_collect.rs

@@ -1,5 +1,6 @@
 use super::NEEDLESS_COLLECT;
 use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_hir_and_then};
+use clippy_utils::higher;
 use clippy_utils::source::{snippet, snippet_with_applicability};
 use clippy_utils::sugg::Sugg;
 use clippy_utils::ty::is_type_diagnostic_item;
@@ -184,10 +185,19 @@ struct IterFunctionVisitor<'a, 'tcx> {
 impl<'tcx> Visitor<'tcx> for IterFunctionVisitor<'_, 'tcx> {
     fn visit_block(&mut self, block: &'tcx Block<'tcx>) {
         for (expr, hir_id) in block.stmts.iter().filter_map(get_expr_and_hir_id_from_stmt) {
+            if check_loop_kind(expr).is_some() {
+                continue;
+            }
             self.visit_block_expr(expr, hir_id);
         }
         if let Some(expr) = block.expr {
-            self.visit_block_expr(expr, None);
+            if let Some(loop_kind) = check_loop_kind(expr) {
+                if let LoopKind::Conditional(block_expr) = loop_kind {
+                    self.visit_block_expr(block_expr, None);
+                }
+            } else {
+                self.visit_block_expr(expr, None);
+            }
         }
     }
 
@@ -264,6 +274,28 @@ impl<'tcx> Visitor<'tcx> for IterFunctionVisitor<'_, 'tcx> {
     }
 }
 
+enum LoopKind<'tcx> {
+    Conditional(&'tcx Expr<'tcx>),
+    Loop,
+}
+
+fn check_loop_kind<'tcx>(expr: &Expr<'tcx>) -> Option<LoopKind<'tcx>> {
+    if let Some(higher::WhileLet { let_expr, .. }) = higher::WhileLet::hir(expr) {
+        return Some(LoopKind::Conditional(let_expr));
+    }
+    if let Some(higher::While { condition, .. }) = higher::While::hir(expr) {
+        return Some(LoopKind::Conditional(condition));
+    }
+    if let Some(higher::ForLoop { arg, .. }) = higher::ForLoop::hir(expr) {
+        return Some(LoopKind::Conditional(arg));
+    }
+    if let ExprKind::Loop { .. } = expr.kind {
+        return Some(LoopKind::Loop);
+    }
+
+    None
+}
+
 impl<'tcx> IterFunctionVisitor<'_, 'tcx> {
     fn visit_block_expr(&mut self, expr: &'tcx Expr<'tcx>, hir_id: Option<HirId>) {
         self.current_statement_hir_id = hir_id;

src/tools/clippy/clippy_lints/src/manual_async_fn.rs

@@ -192,7 +192,7 @@ fn suggested_ret(cx: &LateContext<'_>, output: &Ty<'_>) -> Option<(&'static str,
     match output.kind {
         TyKind::Tup(tys) if tys.is_empty() => {
             let sugg = "remove the return type";
-            Some((sugg, "".into()))
+            Some((sugg, String::new()))
         },
         _ => {
             let sugg = "return the output of the future directly";

src/tools/clippy/clippy_lints/src/manual_ok_or.rs

@@ -1,95 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::{indent_of, reindent_multiline, snippet_opt};
-use clippy_utils::ty::is_type_diagnostic_item;
-use clippy_utils::{is_lang_ctor, path_to_local_id};
-use if_chain::if_chain;
-use rustc_errors::Applicability;
-use rustc_hir::LangItem::{ResultErr, ResultOk};
-use rustc_hir::{Closure, Expr, ExprKind, PatKind};
-use rustc_lint::LintContext;
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::lint::in_external_macro;
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::symbol::sym;
-
-declare_clippy_lint! {
-    /// ### What it does
-    ///
-    /// Finds patterns that reimplement `Option::ok_or`.
-    ///
-    /// ### Why is this bad?
-    ///
-    /// Concise code helps focusing on behavior instead of boilerplate.
-    ///
-    /// ### Examples
-    /// ```rust
-    /// let foo: Option<i32> = None;
-    /// foo.map_or(Err("error"), |v| Ok(v));
-    /// ```
-    ///
-    /// Use instead:
-    /// ```rust
-    /// let foo: Option<i32> = None;
-    /// foo.ok_or("error");
-    /// ```
-    #[clippy::version = "1.49.0"]
-    pub MANUAL_OK_OR,
-    pedantic,
-    "finds patterns that can be encoded more concisely with `Option::ok_or`"
-}
-
-declare_lint_pass!(ManualOkOr => [MANUAL_OK_OR]);
-
-impl<'tcx> LateLintPass<'tcx> for ManualOkOr {
-    fn check_expr(&mut self, cx: &LateContext<'tcx>, scrutinee: &'tcx Expr<'tcx>) {
-        if in_external_macro(cx.sess(), scrutinee.span) {
-            return;
-        }
-
-        if_chain! {
-            if let ExprKind::MethodCall(method_segment, [receiver, or_expr, map_expr], _) = scrutinee.kind;
-            if method_segment.ident.name == sym!(map_or);
-            let ty = cx.typeck_results().expr_ty(receiver);
-            if is_type_diagnostic_item(cx, ty, sym::Option);
-            if is_ok_wrapping(cx, map_expr);
-            if let ExprKind::Call(Expr { kind: ExprKind::Path(err_path), .. }, &[ref err_arg]) = or_expr.kind;
-            if is_lang_ctor(cx, err_path, ResultErr);
-            if let Some(method_receiver_snippet) = snippet_opt(cx, receiver.span);
-            if let Some(err_arg_snippet) = snippet_opt(cx, err_arg.span);
-            if let Some(indent) = indent_of(cx, scrutinee.span);
-            then {
-                let reindented_err_arg_snippet =
-                    reindent_multiline(err_arg_snippet.into(), true, Some(indent + 4));
-                span_lint_and_sugg(
-                    cx,
-                    MANUAL_OK_OR,
-                    scrutinee.span,
-                    "this pattern reimplements `Option::ok_or`",
-                    "replace with",
-                    format!(
-                        "{}.ok_or({})",
-                        method_receiver_snippet,
-                        reindented_err_arg_snippet
-                    ),
-                    Applicability::MachineApplicable,
-                );
-            }
-        }
-    }
-}
-
-fn is_ok_wrapping(cx: &LateContext<'_>, map_expr: &Expr<'_>) -> bool {
-    if let ExprKind::Path(ref qpath) = map_expr.kind {
-        if is_lang_ctor(cx, qpath, ResultOk) {
-            return true;
-        }
-    }
-    if_chain! {
-        if let ExprKind::Closure(&Closure { body, .. }) = map_expr.kind;
-        let body = cx.tcx.hir().body(body);
-        if let PatKind::Binding(_, param_id, ..) = body.params[0].pat.kind;
-        if let ExprKind::Call(Expr { kind: ExprKind::Path(ok_path), .. }, &[ref ok_arg]) = body.value.kind;
-        if is_lang_ctor(cx, ok_path, ResultOk);
-        then { path_to_local_id(ok_arg, param_id) } else { false }
-    }
-}

src/tools/clippy/clippy_lints/src/manual_string_new.rs

@@ -0,0 +1,140 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use rustc_ast::LitKind;
+use rustc_errors::Applicability::MachineApplicable;
+use rustc_hir::{Expr, ExprKind, PathSegment, QPath, TyKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::ty;
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::{sym, symbol, Span};
+
+declare_clippy_lint! {
+    /// ### What it does
+    ///
+    /// Checks for usage of `""` to create a `String`, such as `"".to_string()`, `"".to_owned()`,
+    /// `String::from("")` and others.
+    ///
+    /// ### Why is this bad?
+    ///
+    /// Different ways of creating an empty string makes your code less standardized, which can
+    /// be confusing.
+    ///
+    /// ### Example
+    /// ```rust
+    /// let a = "".to_string();
+    /// let b: String = "".into();
+    /// ```
+    /// Use instead:
+    /// ```rust
+    /// let a = String::new();
+    /// let b = String::new();
+    /// ```
+    #[clippy::version = "1.65.0"]
+    pub MANUAL_STRING_NEW,
+    pedantic,
+    "empty String is being created manually"
+}
+declare_lint_pass!(ManualStringNew => [MANUAL_STRING_NEW]);
+
+impl LateLintPass<'_> for ManualStringNew {
+    fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
+        if expr.span.from_expansion() {
+            return;
+        }
+
+        let ty = cx.typeck_results().expr_ty(expr);
+        match ty.kind() {
+            ty::Adt(adt_def, _) if adt_def.is_struct() => {
+                if !cx.tcx.is_diagnostic_item(sym::String, adt_def.did()) {
+                    return;
+                }
+            },
+            _ => return,
+        }
+
+        match expr.kind {
+            ExprKind::Call(func, args) => {
+                parse_call(cx, expr.span, func, args);
+            },
+            ExprKind::MethodCall(path_segment, args, _) => {
+                parse_method_call(cx, expr.span, path_segment, args);
+            },
+            _ => (),
+        }
+    }
+}
+
+/// Checks if an expression's kind corresponds to an empty &str.
+fn is_expr_kind_empty_str(expr_kind: &ExprKind<'_>) -> bool {
+    if  let ExprKind::Lit(lit) = expr_kind &&
+        let LitKind::Str(value, _) = lit.node &&
+        value == symbol::kw::Empty
+    {
+        return true;
+    }
+
+    false
+}
+
+fn warn_then_suggest(cx: &LateContext<'_>, span: Span) {
+    span_lint_and_sugg(
+        cx,
+        MANUAL_STRING_NEW,
+        span,
+        "empty String is being created manually",
+        "consider using",
+        "String::new()".into(),
+        MachineApplicable,
+    );
+}
+
+/// Tries to parse an expression as a method call, emitting the warning if necessary.
+fn parse_method_call(cx: &LateContext<'_>, span: Span, path_segment: &PathSegment<'_>, args: &[Expr<'_>]) {
+    if args.is_empty() {
+        // When parsing TryFrom::try_from(...).expect(...), we will have more than 1 arg.
+        return;
+    }
+
+    let ident = path_segment.ident.as_str();
+    let method_arg_kind = &args[0].kind;
+    if ["to_string", "to_owned", "into"].contains(&ident) && is_expr_kind_empty_str(method_arg_kind) {
+        warn_then_suggest(cx, span);
+    } else if let ExprKind::Call(func, args) = method_arg_kind {
+        // If our first argument is a function call itself, it could be an `unwrap`-like function.
+        // E.g. String::try_from("hello").unwrap(), TryFrom::try_from("").expect("hello"), etc.
+        parse_call(cx, span, func, args);
+    }
+}
+
+/// Tries to parse an expression as a function call, emitting the warning if necessary.
+fn parse_call(cx: &LateContext<'_>, span: Span, func: &Expr<'_>, args: &[Expr<'_>]) {
+    if args.len() != 1 {
+        return;
+    }
+
+    let arg_kind = &args[0].kind;
+    if let ExprKind::Path(qpath) = &func.kind {
+        if let QPath::TypeRelative(_, _) = qpath {
+            // String::from(...) or String::try_from(...)
+            if  let QPath::TypeRelative(ty, path_seg) = qpath &&
+                [sym::from, sym::try_from].contains(&path_seg.ident.name) &&
+                let TyKind::Path(qpath) = &ty.kind &&
+                let QPath::Resolved(_, path) = qpath &&
+                let [path_seg] = path.segments &&
+                path_seg.ident.name == sym::String &&
+                is_expr_kind_empty_str(arg_kind)
+            {
+                warn_then_suggest(cx, span);
+            }
+        } else if let QPath::Resolved(_, path) = qpath {
+            // From::from(...) or TryFrom::try_from(...)
+            if  let [path_seg1, path_seg2] = path.segments &&
+                is_expr_kind_empty_str(arg_kind) && (
+                    (path_seg1.ident.name == sym::From && path_seg2.ident.name == sym::from) ||
+                    (path_seg1.ident.name == sym::TryFrom && path_seg2.ident.name == sym::try_from)
+                )
+            {
+                warn_then_suggest(cx, span);
+            }
+        }
+    }
+}

src/tools/clippy/clippy_lints/src/map_clone.rs

@@ -1,167 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::source::snippet_with_applicability;
-use clippy_utils::ty::{is_copy, is_type_diagnostic_item};
-use clippy_utils::{is_trait_method, meets_msrv, msrvs, peel_blocks};
-use if_chain::if_chain;
-use rustc_errors::Applicability;
-use rustc_hir as hir;
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::mir::Mutability;
-use rustc_middle::ty;
-use rustc_middle::ty::adjustment::Adjust;
-use rustc_semver::RustcVersion;
-use rustc_session::{declare_tool_lint, impl_lint_pass};
-use rustc_span::symbol::Ident;
-use rustc_span::{sym, Span};
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for usage of `map(|x| x.clone())` or
-    /// dereferencing closures for `Copy` types, on `Iterator` or `Option`,
-    /// and suggests `cloned()` or `copied()` instead
-    ///
-    /// ### Why is this bad?
-    /// Readability, this can be written more concisely
-    ///
-    /// ### Example
-    /// ```rust
-    /// let x = vec![42, 43];
-    /// let y = x.iter();
-    /// let z = y.map(|i| *i);
-    /// ```
-    ///
-    /// The correct use would be:
-    ///
-    /// ```rust
-    /// let x = vec![42, 43];
-    /// let y = x.iter();
-    /// let z = y.cloned();
-    /// ```
-    #[clippy::version = "pre 1.29.0"]
-    pub MAP_CLONE,
-    style,
-    "using `iterator.map(|x| x.clone())`, or dereferencing closures for `Copy` types"
-}
-
-pub struct MapClone {
-    msrv: Option<RustcVersion>,
-}
-
-impl_lint_pass!(MapClone => [MAP_CLONE]);
-
-impl MapClone {
-    pub fn new(msrv: Option<RustcVersion>) -> Self {
-        Self { msrv }
-    }
-}
-
-impl<'tcx> LateLintPass<'tcx> for MapClone {
-    fn check_expr(&mut self, cx: &LateContext<'_>, e: &hir::Expr<'_>) {
-        if e.span.from_expansion() {
-            return;
-        }
-
-        if_chain! {
-            if let hir::ExprKind::MethodCall(method, args, _) = e.kind;
-            if args.len() == 2;
-            if method.ident.name == sym::map;
-            let ty = cx.typeck_results().expr_ty(&args[0]);
-            if is_type_diagnostic_item(cx, ty, sym::Option) || is_trait_method(cx, e, sym::Iterator);
-            if let hir::ExprKind::Closure(&hir::Closure { body, .. }) = args[1].kind;
-            then {
-                let closure_body = cx.tcx.hir().body(body);
-                let closure_expr = peel_blocks(&closure_body.value);
-                match closure_body.params[0].pat.kind {
-                    hir::PatKind::Ref(inner, hir::Mutability::Not) => if let hir::PatKind::Binding(
-                        hir::BindingAnnotation::Unannotated, .., name, None
-                    ) = inner.kind {
-                        if ident_eq(name, closure_expr) {
-                            self.lint_explicit_closure(cx, e.span, args[0].span, true);
-                        }
-                    },
-                    hir::PatKind::Binding(hir::BindingAnnotation::Unannotated, .., name, None) => {
-                        match closure_expr.kind {
-                            hir::ExprKind::Unary(hir::UnOp::Deref, inner) => {
-                                if ident_eq(name, inner) {
-                                    if let ty::Ref(.., Mutability::Not) = cx.typeck_results().expr_ty(inner).kind() {
-                                        self.lint_explicit_closure(cx, e.span, args[0].span, true);
-                                    }
-                                }
-                            },
-                            hir::ExprKind::MethodCall(method, [obj], _) => if_chain! {
-                                if ident_eq(name, obj) && method.ident.name == sym::clone;
-                                if let Some(fn_id) = cx.typeck_results().type_dependent_def_id(closure_expr.hir_id);
-                                if let Some(trait_id) = cx.tcx.trait_of_item(fn_id);
-                                if cx.tcx.lang_items().clone_trait().map_or(false, |id| id == trait_id);
-                                // no autoderefs
-                                if !cx.typeck_results().expr_adjustments(obj).iter()
-                                    .any(|a| matches!(a.kind, Adjust::Deref(Some(..))));
-                                then {
-                                    let obj_ty = cx.typeck_results().expr_ty(obj);
-                                    if let ty::Ref(_, ty, mutability) = obj_ty.kind() {
-                                        if matches!(mutability, Mutability::Not) {
-                                            let copy = is_copy(cx, *ty);
-                                            self.lint_explicit_closure(cx, e.span, args[0].span, copy);
-                                        }
-                                    } else {
-                                        lint_needless_cloning(cx, e.span, args[0].span);
-                                    }
-                                }
-                            },
-                            _ => {},
-                        }
-                    },
-                    _ => {},
-                }
-            }
-        }
-    }
-
-    extract_msrv_attr!(LateContext);
-}
-
-fn ident_eq(name: Ident, path: &hir::Expr<'_>) -> bool {
-    if let hir::ExprKind::Path(hir::QPath::Resolved(None, path)) = path.kind {
-        path.segments.len() == 1 && path.segments[0].ident == name
-    } else {
-        false
-    }
-}
-
-fn lint_needless_cloning(cx: &LateContext<'_>, root: Span, receiver: Span) {
-    span_lint_and_sugg(
-        cx,
-        MAP_CLONE,
-        root.trim_start(receiver).unwrap(),
-        "you are needlessly cloning iterator elements",
-        "remove the `map` call",
-        String::new(),
-        Applicability::MachineApplicable,
-    );
-}
-
-impl MapClone {
-    fn lint_explicit_closure(&self, cx: &LateContext<'_>, replace: Span, root: Span, is_copy: bool) {
-        let mut applicability = Applicability::MachineApplicable;
-
-        let (message, sugg_method) = if is_copy && meets_msrv(self.msrv, msrvs::ITERATOR_COPIED) {
-            ("you are using an explicit closure for copying elements", "copied")
-        } else {
-            ("you are using an explicit closure for cloning elements", "cloned")
-        };
-
-        span_lint_and_sugg(
-            cx,
-            MAP_CLONE,
-            replace,
-            message,
-            &format!("consider calling the dedicated `{}` method", sugg_method),
-            format!(
-                "{}.{}()",
-                snippet_with_applicability(cx, root, "..", &mut applicability),
-                sugg_method,
-            ),
-            applicability,
-        );
-    }
-}

src/tools/clippy/clippy_lints/src/map_err_ignore.rs

@@ -1,154 +0,0 @@
-use clippy_utils::diagnostics::span_lint_and_help;
-use rustc_hir::{CaptureBy, Closure, Expr, ExprKind, PatKind};
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for instances of `map_err(|_| Some::Enum)`
-    ///
-    /// ### Why is this bad?
-    /// This `map_err` throws away the original error rather than allowing the enum to contain and report the cause of the error
-    ///
-    /// ### Example
-    /// Before:
-    /// ```rust
-    /// use std::fmt;
-    ///
-    /// #[derive(Debug)]
-    /// enum Error {
-    ///     Indivisible,
-    ///     Remainder(u8),
-    /// }
-    ///
-    /// impl fmt::Display for Error {
-    ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-    ///         match self {
-    ///             Error::Indivisible => write!(f, "could not divide input by three"),
-    ///             Error::Remainder(remainder) => write!(
-    ///                 f,
-    ///                 "input is not divisible by three, remainder = {}",
-    ///                 remainder
-    ///             ),
-    ///         }
-    ///     }
-    /// }
-    ///
-    /// impl std::error::Error for Error {}
-    ///
-    /// fn divisible_by_3(input: &str) -> Result<(), Error> {
-    ///     input
-    ///         .parse::<i32>()
-    ///         .map_err(|_| Error::Indivisible)
-    ///         .map(|v| v % 3)
-    ///         .and_then(|remainder| {
-    ///             if remainder == 0 {
-    ///                 Ok(())
-    ///             } else {
-    ///                 Err(Error::Remainder(remainder as u8))
-    ///             }
-    ///         })
-    /// }
-    ///  ```
-    ///
-    ///  After:
-    ///  ```rust
-    /// use std::{fmt, num::ParseIntError};
-    ///
-    /// #[derive(Debug)]
-    /// enum Error {
-    ///     Indivisible(ParseIntError),
-    ///     Remainder(u8),
-    /// }
-    ///
-    /// impl fmt::Display for Error {
-    ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-    ///         match self {
-    ///             Error::Indivisible(_) => write!(f, "could not divide input by three"),
-    ///             Error::Remainder(remainder) => write!(
-    ///                 f,
-    ///                 "input is not divisible by three, remainder = {}",
-    ///                 remainder
-    ///             ),
-    ///         }
-    ///     }
-    /// }
-    ///
-    /// impl std::error::Error for Error {
-    ///     fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
-    ///         match self {
-    ///             Error::Indivisible(source) => Some(source),
-    ///             _ => None,
-    ///         }
-    ///     }
-    /// }
-    ///
-    /// fn divisible_by_3(input: &str) -> Result<(), Error> {
-    ///     input
-    ///         .parse::<i32>()
-    ///         .map_err(Error::Indivisible)
-    ///         .map(|v| v % 3)
-    ///         .and_then(|remainder| {
-    ///             if remainder == 0 {
-    ///                 Ok(())
-    ///             } else {
-    ///                 Err(Error::Remainder(remainder as u8))
-    ///             }
-    ///         })
-    /// }
-    /// ```
-    #[clippy::version = "1.48.0"]
-    pub MAP_ERR_IGNORE,
-    restriction,
-    "`map_err` should not ignore the original error"
-}
-
-declare_lint_pass!(MapErrIgnore => [MAP_ERR_IGNORE]);
-
-impl<'tcx> LateLintPass<'tcx> for MapErrIgnore {
-    // do not try to lint if this is from a macro or desugaring
-    fn check_expr(&mut self, cx: &LateContext<'_>, e: &Expr<'_>) {
-        if e.span.from_expansion() {
-            return;
-        }
-
-        // check if this is a method call (e.g. x.foo())
-        if let ExprKind::MethodCall(method, [_, arg], _) = e.kind {
-            // only work if the method name is `map_err` and there are only 2 arguments (e.g. x.map_err(|_|[1]
-            // Enum::Variant[2]))
-            if method.ident.name == sym!(map_err) {
-                // make sure the first argument is a closure, and grab the CaptureRef, BodyId, and fn_decl_span
-                // fields
-                if let ExprKind::Closure(&Closure {
-                    capture_clause,
-                    body,
-                    fn_decl_span,
-                    ..
-                }) = arg.kind
-                {
-                    // check if this is by Reference (meaning there's no move statement)
-                    if capture_clause == CaptureBy::Ref {
-                        // Get the closure body to check the parameters and values
-                        let closure_body = cx.tcx.hir().body(body);
-                        // make sure there's only one parameter (`|_|`)
-                        if closure_body.params.len() == 1 {
-                            // make sure that parameter is the wild token (`_`)
-                            if let PatKind::Wild = closure_body.params[0].pat.kind {
-                                // span the area of the closure capture and warn that the
-                                // original error will be thrown away
-                                span_lint_and_help(
-                                    cx,
-                                    MAP_ERR_IGNORE,
-                                    fn_decl_span,
-                                    "`map_err(|_|...` wildcard pattern discards the original error",
-                                    None,
-                                    "consider storing the original error as a source in the new error, or silence this warning using an ignored identifier (`.map_err(|_foo| ...`)",
-                                );
-                            }
-                        }
-                    }
-                }
-            }
-        }
-    }
-}

src/tools/clippy/clippy_lints/src/matches/match_like_matches.rs

@@ -1,10 +1,11 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::is_wild;
 use clippy_utils::source::snippet_with_applicability;
+use clippy_utils::span_contains_comment;
 use rustc_ast::{Attribute, LitKind};
 use rustc_errors::Applicability;
 use rustc_hir::{Arm, BorrowKind, Expr, ExprKind, Guard, Pat};
-use rustc_lint::LateContext;
+use rustc_lint::{LateContext, LintContext};
 use rustc_middle::ty;
 use rustc_span::source_map::Spanned;
 
@@ -76,6 +77,7 @@ where
         >,
 {
     if_chain! {
+        if !span_contains_comment(cx.sess().source_map(), expr.span);
         if iter.len() >= 2;
         if cx.typeck_results().expr_ty(expr).is_bool();
         if let Some((_, last_pat_opt, last_expr, _)) = iter.next_back();

src/tools/clippy/clippy_lints/src/matches/needless_match.rs

@@ -8,7 +8,7 @@ use clippy_utils::{
 };
 use rustc_errors::Applicability;
 use rustc_hir::LangItem::OptionNone;
-use rustc_hir::{Arm, BindingAnnotation, Expr, ExprKind, FnRetTy, Node, Pat, PatKind, Path, QPath};
+use rustc_hir::{Arm, BindingAnnotation, Expr, ExprKind, FnRetTy, Guard, Node, Pat, PatKind, Path, QPath};
 use rustc_lint::LateContext;
 use rustc_span::sym;
 use rustc_typeck::hir_ty_to_ty;
@@ -65,8 +65,26 @@ pub(crate) fn check_if_let<'tcx>(cx: &LateContext<'tcx>, ex: &Expr<'_>, if_let:
 fn check_all_arms(cx: &LateContext<'_>, match_expr: &Expr<'_>, arms: &[Arm<'_>]) -> bool {
     for arm in arms {
         let arm_expr = peel_blocks_with_stmt(arm.body);
+
+        if let Some(guard_expr) = &arm.guard {
+            match guard_expr {
+                // gives up if `pat if expr` can have side effects
+                Guard::If(if_cond) => {
+                    if if_cond.can_have_side_effects() {
+                        return false;
+                    }
+                },
+                // gives up `pat if let ...` arm
+                Guard::IfLet(_) => {
+                    return false;
+                },
+            };
+        }
+
         if let PatKind::Wild = arm.pat.kind {
-            return eq_expr_value(cx, match_expr, strip_return(arm_expr));
+            if !eq_expr_value(cx, match_expr, strip_return(arm_expr)) {
+                return false;
+            }
         } else if !pat_same_as_expr(arm.pat, arm_expr) {
             return false;
         }

src/tools/clippy/clippy_lints/src/methods/bytecount.rs

@@ -0,0 +1,70 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_with_applicability;
+use clippy_utils::ty::match_type;
+use clippy_utils::visitors::is_local_used;
+use clippy_utils::{path_to_local_id, paths, peel_blocks, peel_ref_operators, strip_pat_refs};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir::{BinOpKind, Closure, Expr, ExprKind, PatKind};
+use rustc_lint::LateContext;
+use rustc_middle::ty::{self, UintTy};
+use rustc_span::sym;
+
+use super::NAIVE_BYTECOUNT;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'_>,
+    filter_recv: &'tcx Expr<'_>,
+    filter_arg: &'tcx Expr<'_>,
+) {
+    if_chain! {
+        if let ExprKind::Closure(&Closure { body, .. }) = filter_arg.kind;
+        let body = cx.tcx.hir().body(body);
+        if let [param] = body.params;
+        if let PatKind::Binding(_, arg_id, _, _) = strip_pat_refs(param.pat).kind;
+        if let ExprKind::Binary(ref op, l, r) = body.value.kind;
+        if op.node == BinOpKind::Eq;
+        if match_type(cx,
+                    cx.typeck_results().expr_ty(filter_recv).peel_refs(),
+                    &paths::SLICE_ITER);
+        let operand_is_arg = |expr| {
+            let expr = peel_ref_operators(cx, peel_blocks(expr));
+            path_to_local_id(expr, arg_id)
+        };
+        let needle = if operand_is_arg(l) {
+            r
+        } else if operand_is_arg(r) {
+            l
+        } else {
+            return;
+        };
+        if ty::Uint(UintTy::U8) == *cx.typeck_results().expr_ty(needle).peel_refs().kind();
+        if !is_local_used(cx, needle, arg_id);
+        then {
+            let haystack = if let ExprKind::MethodCall(path, args, _) =
+                    filter_recv.kind {
+                let p = path.ident.name;
+                if (p == sym::iter || p == sym!(iter_mut)) && args.len() == 1 {
+                    &args[0]
+                } else {
+                    filter_recv
+                }
+            } else {
+                filter_recv
+            };
+            let mut applicability = Applicability::MaybeIncorrect;
+            span_lint_and_sugg(
+                cx,
+                NAIVE_BYTECOUNT,
+                expr.span,
+                "you appear to be counting bytes the naive way",
+                "consider using the bytecount crate",
+                format!("bytecount::count({}, {})",
+                        snippet_with_applicability(cx, haystack.span, "..", &mut applicability),
+                        snippet_with_applicability(cx, needle.span, "..", &mut applicability)),
+                applicability,
+            );
+        }
+    };
+}

src/tools/clippy/clippy_lints/src/methods/bytes_count_to_len.rs

@@ -0,0 +1,37 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_with_applicability;
+use clippy_utils::ty::is_type_diagnostic_item;
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_lint::LateContext;
+use rustc_span::sym;
+
+use super::BYTES_COUNT_TO_LEN;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx hir::Expr<'_>,
+    count_recv: &'tcx hir::Expr<'_>,
+    bytes_recv: &'tcx hir::Expr<'_>,
+) {
+    if_chain! {
+        if let Some(bytes_id) = cx.typeck_results().type_dependent_def_id(count_recv.hir_id);
+        if let Some(impl_id) = cx.tcx.impl_of_method(bytes_id);
+        if cx.tcx.type_of(impl_id).is_str();
+        let ty = cx.typeck_results().expr_ty(bytes_recv).peel_refs();
+        if ty.is_str() || is_type_diagnostic_item(cx, ty, sym::String);
+        then {
+            let mut applicability = Applicability::MachineApplicable;
+            span_lint_and_sugg(
+                cx,
+                BYTES_COUNT_TO_LEN,
+                expr.span,
+                "using long and hard to read `.bytes().count()`",
+                "consider calling `.len()` instead",
+                format!("{}.len()", snippet_with_applicability(cx, bytes_recv.span, "..", &mut applicability)),
+                applicability
+            );
+        }
+    };
+}

src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs

@@ -0,0 +1,41 @@
+use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::ty::is_type_diagnostic_item;
+use if_chain::if_chain;
+use rustc_ast::ast::LitKind;
+use rustc_hir::{Expr, ExprKind};
+use rustc_lint::LateContext;
+use rustc_span::{source_map::Spanned, symbol::sym, Span};
+
+use super::CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'_>,
+    call_span: Span,
+    recv: &'tcx Expr<'_>,
+    arg: &'tcx Expr<'_>,
+) {
+    if_chain! {
+        if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
+        if let Some(impl_id) = cx.tcx.impl_of_method(method_id);
+        if cx.tcx.type_of(impl_id).is_str();
+        if let ExprKind::Lit(Spanned { node: LitKind::Str(ext_literal, ..), ..}) = arg.kind;
+        if (2..=6).contains(&ext_literal.as_str().len());
+        let ext_str = ext_literal.as_str();
+        if ext_str.starts_with('.');
+        if ext_str.chars().skip(1).all(|c| c.is_uppercase() || c.is_ascii_digit())
+            || ext_str.chars().skip(1).all(|c| c.is_lowercase() || c.is_ascii_digit());
+        let recv_ty = cx.typeck_results().expr_ty(recv).peel_refs();
+        if recv_ty.is_str() || is_type_diagnostic_item(cx, recv_ty, sym::String);
+        then {
+            span_lint_and_help(
+                cx,
+                CASE_SENSITIVE_FILE_EXTENSION_COMPARISONS,
+                call_span,
+                "case-sensitive file extension comparison",
+                None,
+                "consider using a case-insensitive comparison instead",
+            );
+        }
+    }
+}

src/tools/clippy/clippy_lints/src/methods/collapsible_str_replace.rs

@@ -0,0 +1,96 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet;
+use clippy_utils::visitors::for_each_expr;
+use clippy_utils::{eq_expr_value, get_parent_expr};
+use core::ops::ControlFlow;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_lint::LateContext;
+use std::collections::VecDeque;
+
+use super::method_call;
+use super::COLLAPSIBLE_STR_REPLACE;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx hir::Expr<'tcx>,
+    from: &'tcx hir::Expr<'tcx>,
+    to: &'tcx hir::Expr<'tcx>,
+) {
+    let replace_methods = collect_replace_calls(cx, expr, to);
+    if replace_methods.methods.len() > 1 {
+        let from_kind = cx.typeck_results().expr_ty(from).peel_refs().kind();
+        // If the parent node's `to` argument is the same as the `to` argument
+        // of the last replace call in the current chain, don't lint as it was already linted
+        if let Some(parent) = get_parent_expr(cx, expr)
+            && let Some(("replace", [_, current_from, current_to], _)) = method_call(parent)
+            && eq_expr_value(cx, to, current_to)
+            && from_kind == cx.typeck_results().expr_ty(current_from).peel_refs().kind()
+        {
+            return;
+        }
+
+        check_consecutive_replace_calls(cx, expr, &replace_methods, to);
+    }
+}
+
+struct ReplaceMethods<'tcx> {
+    methods: VecDeque<&'tcx hir::Expr<'tcx>>,
+    from_args: VecDeque<&'tcx hir::Expr<'tcx>>,
+}
+
+fn collect_replace_calls<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx hir::Expr<'tcx>,
+    to_arg: &'tcx hir::Expr<'tcx>,
+) -> ReplaceMethods<'tcx> {
+    let mut methods = VecDeque::new();
+    let mut from_args = VecDeque::new();
+
+    let _: Option<()> = for_each_expr(expr, |e| {
+        if let Some(("replace", [_, from, to], _)) = method_call(e) {
+            if eq_expr_value(cx, to_arg, to) && cx.typeck_results().expr_ty(from).peel_refs().is_char() {
+                methods.push_front(e);
+                from_args.push_front(from);
+                ControlFlow::Continue(())
+            } else {
+                ControlFlow::BREAK
+            }
+        } else {
+            ControlFlow::Continue(())
+        }
+    });
+
+    ReplaceMethods { methods, from_args }
+}
+
+/// Check a chain of `str::replace` calls for `collapsible_str_replace` lint.
+fn check_consecutive_replace_calls<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx hir::Expr<'tcx>,
+    replace_methods: &ReplaceMethods<'tcx>,
+    to_arg: &'tcx hir::Expr<'tcx>,
+) {
+    let from_args = &replace_methods.from_args;
+    let from_arg_reprs: Vec<String> = from_args
+        .iter()
+        .map(|from_arg| snippet(cx, from_arg.span, "..").to_string())
+        .collect();
+    let app = Applicability::MachineApplicable;
+    let earliest_replace_call = replace_methods.methods.front().unwrap();
+    if let Some((_, [..], span_lo)) = method_call(earliest_replace_call) {
+        span_lint_and_sugg(
+            cx,
+            COLLAPSIBLE_STR_REPLACE,
+            expr.span.with_lo(span_lo.lo()),
+            "used consecutive `str::replace` call",
+            "replace with",
+            format!(
+                "replace([{}], {})",
+                from_arg_reprs.join(", "),
+                snippet(cx, to_arg.span, ".."),
+            ),
+            app,
+        );
+    }
+}

src/tools/clippy/clippy_lints/src/methods/expect_used.rs

@@ -7,18 +7,26 @@ use rustc_span::sym;
 
 use super::EXPECT_USED;
 
-/// lint use of `expect()` for `Option`s and `Result`s
+/// lint use of `expect()` or `expect_err` for `Result` and `expect()` for `Option`.
-pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr<'_>, allow_expect_in_tests: bool) {
+pub(super) fn check(
+    cx: &LateContext<'_>,
+    expr: &hir::Expr<'_>,
+    recv: &hir::Expr<'_>,
+    is_err: bool,
+    allow_expect_in_tests: bool,
+) {
     let obj_ty = cx.typeck_results().expr_ty(recv).peel_refs();
 
-    let mess = if is_type_diagnostic_item(cx, obj_ty, sym::Option) {
+    let mess = if is_type_diagnostic_item(cx, obj_ty, sym::Option) && !is_err {
         Some((EXPECT_USED, "an Option", "None", ""))
     } else if is_type_diagnostic_item(cx, obj_ty, sym::Result) {
-        Some((EXPECT_USED, "a Result", "Err", "an "))
+        Some((EXPECT_USED, "a Result", if is_err { "Ok" } else { "Err" }, "an "))
     } else {
         None
     };
 
+    let method = if is_err { "expect_err" } else { "expect" };
+
     if allow_expect_in_tests && is_in_test_function(cx.tcx, expr.hir_id) {
         return;
     }
@@ -28,7 +36,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr
             cx,
             lint,
             expr.span,
-            &format!("used `expect()` on `{kind}` value"),
+            &format!("used `{method}()` on `{kind}` value"),
             None,
             &format!("if this value is {none_prefix}`{none_value}`, it will panic"),
         );

src/tools/clippy/clippy_lints/src/methods/get_first.rs

@@ -0,0 +1,39 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::is_slice_of_primitives;
+use clippy_utils::source::snippet_with_applicability;
+use if_chain::if_chain;
+use rustc_ast::LitKind;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_lint::LateContext;
+use rustc_span::source_map::Spanned;
+
+use super::GET_FIRST;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx hir::Expr<'_>,
+    recv: &'tcx hir::Expr<'_>,
+    arg: &'tcx hir::Expr<'_>,
+) {
+    if_chain! {
+        if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
+        if let Some(impl_id) = cx.tcx.impl_of_method(method_id);
+        if cx.tcx.type_of(impl_id).is_slice();
+        if let Some(_) = is_slice_of_primitives(cx, recv);
+        if let hir::ExprKind::Lit(Spanned { node: LitKind::Int(0, _), .. }) = arg.kind;
+        then {
+            let mut app = Applicability::MachineApplicable;
+            let slice_name = snippet_with_applicability(cx, recv.span, "..", &mut app);
+            span_lint_and_sugg(
+                cx,
+                GET_FIRST,
+                expr.span,
+                &format!("accessing first element with `{0}.get(0)`", slice_name),
+                "try",
+                format!("{}.first()", slice_name),
+                app,
+            );
+        }
+    }
+}

src/tools/clippy/clippy_lints/src/methods/iter_on_single_or_empty_collections.rs

@@ -0,0 +1,107 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet;
+use clippy_utils::{get_expr_use_or_unification_node, is_lang_ctor, is_no_std_crate};
+
+use rustc_errors::Applicability;
+use rustc_hir::LangItem::{OptionNone, OptionSome};
+use rustc_hir::{Expr, ExprKind, Node};
+use rustc_lint::LateContext;
+
+use super::{ITER_ON_EMPTY_COLLECTIONS, ITER_ON_SINGLE_ITEMS};
+
+enum IterType {
+    Iter,
+    IterMut,
+    IntoIter,
+}
+
+impl IterType {
+    fn ref_prefix(&self) -> &'static str {
+        match self {
+            Self::Iter => "&",
+            Self::IterMut => "&mut ",
+            Self::IntoIter => "",
+        }
+    }
+}
+
+pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'_>, method_name: &str, recv: &Expr<'_>) {
+    let item = match &recv.kind {
+        ExprKind::Array(v) if v.len() <= 1 => v.first(),
+        ExprKind::Path(p) => {
+            if is_lang_ctor(cx, p, OptionNone) {
+                None
+            } else {
+                return;
+            }
+        },
+        ExprKind::Call(f, some_args) if some_args.len() == 1 => {
+            if let ExprKind::Path(p) = &f.kind {
+                if is_lang_ctor(cx, p, OptionSome) {
+                    Some(&some_args[0])
+                } else {
+                    return;
+                }
+            } else {
+                return;
+            }
+        },
+        _ => return,
+    };
+    let iter_type = match method_name {
+        "iter" => IterType::Iter,
+        "iter_mut" => IterType::IterMut,
+        "into_iter" => IterType::IntoIter,
+        _ => return,
+    };
+
+    let is_unified = match get_expr_use_or_unification_node(cx.tcx, expr) {
+        Some((Node::Expr(parent), child_id)) => match parent.kind {
+            ExprKind::If(e, _, _) | ExprKind::Match(e, _, _) if e.hir_id == child_id => false,
+            ExprKind::If(_, _, _)
+            | ExprKind::Match(_, _, _)
+            | ExprKind::Closure(_)
+            | ExprKind::Ret(_)
+            | ExprKind::Break(_, _) => true,
+            _ => false,
+        },
+        Some((Node::Stmt(_) | Node::Local(_), _)) => false,
+        _ => true,
+    };
+
+    if is_unified {
+        return;
+    }
+
+    if let Some(i) = item {
+        let sugg = format!(
+            "{}::iter::once({}{})",
+            if is_no_std_crate(cx) { "core" } else { "std" },
+            iter_type.ref_prefix(),
+            snippet(cx, i.span, "...")
+        );
+        span_lint_and_sugg(
+            cx,
+            ITER_ON_SINGLE_ITEMS,
+            expr.span,
+            &format!("`{method_name}` call on a collection with only one item"),
+            "try",
+            sugg,
+            Applicability::MaybeIncorrect,
+        );
+    } else {
+        span_lint_and_sugg(
+            cx,
+            ITER_ON_EMPTY_COLLECTIONS,
+            expr.span,
+            &format!("`{method_name}` call on an empty collection"),
+            "try",
+            if is_no_std_crate(cx) {
+                "core::iter::empty()".to_string()
+            } else {
+                "std::iter::empty()".to_string()
+            },
+            Applicability::MaybeIncorrect,
+        );
+    }
+}

src/tools/clippy/clippy_lints/src/methods/manual_ok_or.rs

@@ -0,0 +1,64 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::{indent_of, reindent_multiline, snippet_opt};
+use clippy_utils::ty::is_type_diagnostic_item;
+use clippy_utils::{is_lang_ctor, path_to_local_id};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir::LangItem::{ResultErr, ResultOk};
+use rustc_hir::{Closure, Expr, ExprKind, PatKind};
+use rustc_lint::LateContext;
+use rustc_span::symbol::sym;
+
+use super::MANUAL_OK_OR;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'tcx>,
+    recv: &'tcx Expr<'_>,
+    or_expr: &'tcx Expr<'_>,
+    map_expr: &'tcx Expr<'_>,
+) {
+    if_chain! {
+        if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
+        if let Some(impl_id) = cx.tcx.impl_of_method(method_id);
+        if is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id), sym::Option);
+        if let ExprKind::Call(Expr { kind: ExprKind::Path(err_path), .. }, [err_arg]) = or_expr.kind;
+        if is_lang_ctor(cx, err_path, ResultErr);
+        if is_ok_wrapping(cx, map_expr);
+        if let Some(recv_snippet) = snippet_opt(cx, recv.span);
+        if let Some(err_arg_snippet) = snippet_opt(cx, err_arg.span);
+        if let Some(indent) = indent_of(cx, expr.span);
+        then {
+            let reindented_err_arg_snippet = reindent_multiline(err_arg_snippet.into(), true, Some(indent + 4));
+            span_lint_and_sugg(
+                cx,
+                MANUAL_OK_OR,
+                expr.span,
+                "this pattern reimplements `Option::ok_or`",
+                "replace with",
+                format!(
+                    "{}.ok_or({})",
+                    recv_snippet,
+                    reindented_err_arg_snippet
+                ),
+                Applicability::MachineApplicable,
+            );
+        }
+    }
+}
+
+fn is_ok_wrapping(cx: &LateContext<'_>, map_expr: &Expr<'_>) -> bool {
+    if let ExprKind::Path(ref qpath) = map_expr.kind {
+        if is_lang_ctor(cx, qpath, ResultOk) {
+            return true;
+        }
+    }
+    if_chain! {
+        if let ExprKind::Closure(&Closure { body, .. }) = map_expr.kind;
+        let body = cx.tcx.hir().body(body);
+        if let PatKind::Binding(_, param_id, ..) = body.params[0].pat.kind;
+        if let ExprKind::Call(Expr { kind: ExprKind::Path(ok_path), .. }, &[ref ok_arg]) = body.value.kind;
+        if is_lang_ctor(cx, ok_path, ResultOk);
+        then { path_to_local_id(ok_arg, param_id) } else { false }
+    }
+}

src/tools/clippy/clippy_lints/src/methods/map_clone.rs

@@ -0,0 +1,122 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet_with_applicability;
+use clippy_utils::ty::{is_copy, is_type_diagnostic_item};
+use clippy_utils::{is_diag_trait_item, meets_msrv, msrvs, peel_blocks};
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_lint::LateContext;
+use rustc_middle::mir::Mutability;
+use rustc_middle::ty;
+use rustc_middle::ty::adjustment::Adjust;
+use rustc_semver::RustcVersion;
+use rustc_span::symbol::Ident;
+use rustc_span::{sym, Span};
+
+use super::MAP_CLONE;
+
+pub(super) fn check<'tcx>(
+    cx: &LateContext<'_>,
+    e: &hir::Expr<'_>,
+    recv: &hir::Expr<'_>,
+    arg: &'tcx hir::Expr<'_>,
+    msrv: Option<RustcVersion>,
+) {
+    if_chain! {
+        if let Some(method_id) = cx.typeck_results().type_dependent_def_id(e.hir_id);
+        if cx.tcx.impl_of_method(method_id)
+            .map_or(false, |id| is_type_diagnostic_item(cx, cx.tcx.type_of(id), sym::Option))
+            || is_diag_trait_item(cx, method_id, sym::Iterator);
+        if let hir::ExprKind::Closure(&hir::Closure{ body, .. }) = arg.kind;
+        then {
+            let closure_body = cx.tcx.hir().body(body);
+            let closure_expr = peel_blocks(&closure_body.value);
+            match closure_body.params[0].pat.kind {
+                hir::PatKind::Ref(inner, hir::Mutability::Not) => if let hir::PatKind::Binding(
+                    hir::BindingAnnotation::Unannotated, .., name, None
+                ) = inner.kind {
+                    if ident_eq(name, closure_expr) {
+                        lint_explicit_closure(cx, e.span, recv.span, true, msrv);
+                    }
+                },
+                hir::PatKind::Binding(hir::BindingAnnotation::Unannotated, .., name, None) => {
+                    match closure_expr.kind {
+                        hir::ExprKind::Unary(hir::UnOp::Deref, inner) => {
+                            if ident_eq(name, inner) {
+                                if let ty::Ref(.., Mutability::Not) = cx.typeck_results().expr_ty(inner).kind() {
+                                    lint_explicit_closure(cx, e.span, recv.span, true, msrv);
+                                }
+                            }
+                        },
+                        hir::ExprKind::MethodCall(method, [obj], _) => if_chain! {
+                            if ident_eq(name, obj) && method.ident.name == sym::clone;
+                            if let Some(fn_id) = cx.typeck_results().type_dependent_def_id(closure_expr.hir_id);
+                            if let Some(trait_id) = cx.tcx.trait_of_item(fn_id);
+                            if cx.tcx.lang_items().clone_trait().map_or(false, |id| id == trait_id);
+                            // no autoderefs
+                            if !cx.typeck_results().expr_adjustments(obj).iter()
+                                .any(|a| matches!(a.kind, Adjust::Deref(Some(..))));
+                            then {
+                                let obj_ty = cx.typeck_results().expr_ty(obj);
+                                if let ty::Ref(_, ty, mutability) = obj_ty.kind() {
+                                    if matches!(mutability, Mutability::Not) {
+                                        let copy = is_copy(cx, *ty);
+                                        lint_explicit_closure(cx, e.span, recv.span, copy, msrv);
+                                    }
+                                } else {
+                                    lint_needless_cloning(cx, e.span, recv.span);
+                                }
+                            }
+                        },
+                        _ => {},
+                    }
+                },
+                _ => {},
+            }
+        }
+    }
+}
+
+fn ident_eq(name: Ident, path: &hir::Expr<'_>) -> bool {
+    if let hir::ExprKind::Path(hir::QPath::Resolved(None, path)) = path.kind {
+        path.segments.len() == 1 && path.segments[0].ident == name
+    } else {
+        false
+    }
+}
+
+fn lint_needless_cloning(cx: &LateContext<'_>, root: Span, receiver: Span) {
+    span_lint_and_sugg(
+        cx,
+        MAP_CLONE,
+        root.trim_start(receiver).unwrap(),
+        "you are needlessly cloning iterator elements",
+        "remove the `map` call",
+        String::new(),
+        Applicability::MachineApplicable,
+    );
+}
+
+fn lint_explicit_closure(cx: &LateContext<'_>, replace: Span, root: Span, is_copy: bool, msrv: Option<RustcVersion>) {
+    let mut applicability = Applicability::MachineApplicable;
+
+    let (message, sugg_method) = if is_copy && meets_msrv(msrv, msrvs::ITERATOR_COPIED) {
+        ("you are using an explicit closure for copying elements", "copied")
+    } else {
+        ("you are using an explicit closure for cloning elements", "cloned")
+    };
+
+    span_lint_and_sugg(
+        cx,
+        MAP_CLONE,
+        replace,
+        message,
+        &format!("consider calling the dedicated `{}` method", sugg_method),
+        format!(
+            "{}.{}()",
+            snippet_with_applicability(cx, root, "..", &mut applicability),
+            sugg_method,
+        ),
+        applicability,
+    );
+}

src/tools/clippy/clippy_lints/src/methods/map_err_ignore.rs

@@ -0,0 +1,34 @@
+use clippy_utils::diagnostics::span_lint_and_help;
+use clippy_utils::ty::is_type_diagnostic_item;
+use rustc_hir::{CaptureBy, Closure, Expr, ExprKind, PatKind};
+use rustc_lint::LateContext;
+use rustc_span::sym;
+
+use super::MAP_ERR_IGNORE;
+
+pub(super) fn check<'tcx>(cx: &LateContext<'_>, e: &Expr<'_>, arg: &'tcx Expr<'_>) {
+    if let Some(method_id) = cx.typeck_results().type_dependent_def_id(e.hir_id)
+        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id), sym::Result)
+        && let ExprKind::Closure(&Closure {
+            capture_clause: CaptureBy::Ref,
+            body,
+            fn_decl_span,
+            ..
+        }) = arg.kind
+        && let closure_body = cx.tcx.hir().body(body)
+        && let [param] = closure_body.params
+        && let PatKind::Wild = param.pat.kind
+    {
+        // span the area of the closure capture and warn that the
+        // original error will be thrown away
+        span_lint_and_help(
+            cx,
+            MAP_ERR_IGNORE,
+            fn_decl_span,
+            "`map_err(|_|...` wildcard pattern discards the original error",
+            None,
+            "consider storing the original error as a source in the new error, or silence this warning using an ignored identifier (`.map_err(|_foo| ...`)",
+        );
+    }
+}

src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs

@@ -0,0 +1,30 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::ty::is_type_diagnostic_item;
+use if_chain::if_chain;
+use rustc_errors::Applicability;
+use rustc_hir::{Expr, Mutability};
+use rustc_lint::LateContext;
+use rustc_middle::ty;
+use rustc_span::{sym, Span};
+
+use super::MUT_MUTEX_LOCK;
+
+pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, ex: &'tcx Expr<'tcx>, recv: &'tcx Expr<'tcx>, name_span: Span) {
+    if_chain! {
+        if let ty::Ref(_, _, Mutability::Mut) = cx.typeck_results().expr_ty(recv).kind();
+        if let Some(method_id) = cx.typeck_results().type_dependent_def_id(ex.hir_id);
+        if let Some(impl_id) = cx.tcx.impl_of_method(method_id);
+        if is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id), sym::Mutex);
+        then {
+            span_lint_and_sugg(
+                cx,
+                MUT_MUTEX_LOCK,
+                name_span,
+                "calling `&mut Mutex::lock` unnecessarily locks an exclusive (mutable) reference",
+                "change this to",
+                "get_mut".to_owned(),
+                Applicability::MaybeIncorrect,
+            );
+        }
+    }
+}