Replace item names containing an error code with something more meaningful

or inline such functions if useless.

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -632,20 +632,19 @@ impl<'a> AstValidator<'a> {
         }
     }
 
-    fn emit_e0568(&self, span: Span, ident: Span) {
-        self.dcx().emit_err(errors::AutoTraitBounds { span, ident });
-    }
-
     fn deny_super_traits(&self, bounds: &GenericBounds, ident_span: Span) {
         if let [.., last] = &bounds[..] {
             let span = ident_span.shrink_to_hi().to(last.span());
-            self.emit_e0568(span, ident_span);
+            self.dcx().emit_err(errors::AutoTraitBounds { span, ident: ident_span });
         }
     }
 
     fn deny_where_clause(&self, where_clause: &WhereClause, ident_span: Span) {
         if !where_clause.predicates.is_empty() {
-            self.emit_e0568(where_clause.span, ident_span);
+            // FIXME: The current diagnostic is misleading since it only talks about
+            // super trait and lifetime bounds while we should just say “bounds”.
+            self.dcx()
+                .emit_err(errors::AutoTraitBounds { span: where_clause.span, ident: ident_span });
         }
     }
 

compiler/rustc_hir_analysis/messages.ftl

@@ -201,6 +201,12 @@ hir_analysis_inherent_ty_outside_relevant = cannot define inherent `impl` for a
     .help = consider moving this inherent impl into the crate defining the type if possible
     .span_help = alternatively add `#[rustc_allow_incoherent_impl]` to the relevant impl items
 
+hir_analysis_invalid_receiver_ty = invalid `self` parameter type: `{$receiver_ty}`
+    .note = type of `self` must be `Self` or a type that dereferences to it
+
+hir_analysis_invalid_receiver_ty_help =
+    consider changing to `self`, `&self`, `&mut self`, `self: Box<Self>`, `self: Rc<Self>`, `self: Arc<Self>`, or `self: Pin<P>` (where P is one of the previous types except `Self`)
+
 hir_analysis_invalid_union_field =
     field must implement `Copy` or be wrapped in `ManuallyDrop<...>` to be used in a union
     .note = union fields must not have drop side-effects, which is currently enforced via either `Copy` or `ManuallyDrop<...>`

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -2,6 +2,7 @@ use crate::autoderef::Autoderef;
 use crate::collect::CollectItemTypesVisitor;
 use crate::constrained_generic_params::{identify_constrained_generic_params, Parameter};
 use crate::errors;
+use crate::fluent_generated as fluent;
 
 use hir::intravisit::Visitor;
 use rustc_ast as ast;
@@ -1636,10 +1637,6 @@ fn check_fn_or_method<'tcx>(
     }
 }
 
-const HELP_FOR_SELF_TYPE: &str = "consider changing to `self`, `&self`, `&mut self`, `self: Box<Self>`, \
-     `self: Rc<Self>`, `self: Arc<Self>`, or `self: Pin<P>` (where P is one \
-     of the previous types except `Self`)";
-
 #[instrument(level = "debug", skip(wfcx))]
 fn check_method_receiver<'tcx>(
     wfcx: &WfCheckingCtxt<'_, 'tcx>,
@@ -1675,7 +1672,7 @@ fn check_method_receiver<'tcx>(
     if tcx.features().arbitrary_self_types {
         if !receiver_is_valid(wfcx, span, receiver_ty, self_ty, true) {
             // Report error; `arbitrary_self_types` was enabled.
-            return Err(e0307(tcx, span, receiver_ty));
+            return Err(tcx.dcx().emit_err(errors::InvalidReceiverTy { span, receiver_ty }));
         }
     } else {
         if !receiver_is_valid(wfcx, span, receiver_ty, self_ty, false) {
@@ -1690,24 +1687,17 @@ fn check_method_receiver<'tcx>(
                          the `arbitrary_self_types` feature",
                     ),
                 )
-                .with_help(HELP_FOR_SELF_TYPE)
+                .with_help(fluent::hir_analysis_invalid_receiver_ty_help)
                 .emit()
             } else {
                 // Report error; would not have worked with `arbitrary_self_types`.
-                e0307(tcx, span, receiver_ty)
+                tcx.dcx().emit_err(errors::InvalidReceiverTy { span, receiver_ty })
             });
         }
     }
     Ok(())
 }
 
-fn e0307(tcx: TyCtxt<'_>, span: Span, receiver_ty: Ty<'_>) -> ErrorGuaranteed {
-    struct_span_code_err!(tcx.dcx(), span, E0307, "invalid `self` parameter type: {receiver_ty}")
-        .with_note("type of `self` must be `Self` or a type that dereferences to it")
-        .with_help(HELP_FOR_SELF_TYPE)
-        .emit()
-}
-
 /// Returns whether `receiver_ty` would be considered a valid receiver type for `self_ty`. If
 /// `arbitrary_self_types` is enabled, `receiver_ty` must transitively deref to `self_ty`, possibly
 /// through a `*const/mut T` raw pointer. If the feature is not enabled, the requirements are more

compiler/rustc_hir_analysis/src/errors.rs

@@ -1641,3 +1641,13 @@ pub struct NonConstRange {
     #[primary_span]
     pub span: Span,
 }
+
+#[derive(Diagnostic)]
+#[diag(hir_analysis_invalid_receiver_ty, code = E0307)]
+#[note]
+#[help(hir_analysis_invalid_receiver_ty_help)]
+pub struct InvalidReceiverTy<'tcx> {
+    #[primary_span]
+    pub span: Span,
+    pub receiver_ty: Ty<'tcx>,
+}

compiler/rustc_hir_typeck/src/pat.rs

@@ -1228,16 +1228,22 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 );
             }
         } else {
-            // Pattern has wrong number of fields.
+            let e = self.emit_err_pat_wrong_number_of_fields(
-            let e =
+                pat.span,
-                self.e0023(pat.span, res, qpath, subpats, &variant.fields.raw, expected, had_err);
+                res,
+                qpath,
+                subpats,
+                &variant.fields.raw,
+                expected,
+                had_err,
+            );
             on_error(e);
             return Ty::new_error(tcx, e);
         }
         pat_ty
     }
 
-    fn e0023(
+    fn emit_err_pat_wrong_number_of_fields(
         &self,
         pat_span: Span,
         res: Res,

compiler/rustc_mir_build/src/thir/pattern/check_match.rs

@@ -10,9 +10,7 @@ use rustc_arena::{DroplessArena, TypedArena};
 use rustc_ast::Mutability;
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_data_structures::stack::ensure_sufficient_stack;
-use rustc_errors::{
+use rustc_errors::{codes::*, struct_span_code_err, Applicability, ErrorGuaranteed, MultiSpan};
-    codes::*, struct_span_code_err, Applicability, Diag, ErrorGuaranteed, MultiSpan,
-};
 use rustc_hir::def::*;
 use rustc_hir::def_id::LocalDefId;
 use rustc_hir::{self as hir, BindingMode, ByRef, HirId};
@@ -24,7 +22,6 @@ use rustc_middle::ty::{self, AdtDef, Ty, TyCtxt};
 use rustc_session::lint::builtin::{
     BINDINGS_WITH_VARIANT_NAME, IRREFUTABLE_LET_PATTERNS, UNREACHABLE_PATTERNS,
 };
-use rustc_session::Session;
 use rustc_span::hygiene::DesugaringKind;
 use rustc_span::{sym, Span};
 
@@ -64,10 +61,6 @@ pub(crate) fn check_match(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Result<(), Err
     visitor.error
 }
 
-fn create_e0004(sess: &Session, sp: Span, error_message: String) -> Diag<'_> {
-    struct_span_code_err!(sess.dcx(), sp, E0004, "{}", &error_message)
-}
-
 #[derive(Debug, Copy, Clone, PartialEq)]
 enum RefutableFlag {
     Irrefutable,
@@ -975,10 +968,11 @@ fn report_non_exhaustive_match<'p, 'tcx>(
 
     // FIXME: migration of this diagnostic will require list support
     let joined_patterns = joined_uncovered_patterns(cx, &witnesses);
-    let mut err = create_e0004(
+    let mut err = struct_span_code_err!(
-        cx.tcx.sess,
+        cx.tcx.dcx(),
         sp,
-        format!("non-exhaustive patterns: {joined_patterns} not covered"),
+        E0004,
+        "non-exhaustive patterns: {joined_patterns} not covered"
     );
     err.span_label(
         sp,

tests/ui/async-await/inference_var_self_argument.rs

@@ -4,7 +4,7 @@
 trait Foo {
     async fn foo(self: &dyn Foo) {
         //~^ ERROR: `Foo` cannot be made into an object
-        //~| ERROR invalid `self` parameter type: &dyn Foo
+        //~| ERROR invalid `self` parameter type: `&dyn Foo`
         todo!()
     }
 }

tests/ui/async-await/inference_var_self_argument.stderr

@@ -13,7 +13,7 @@ LL |     async fn foo(self: &dyn Foo) {
    |              ^^^ ...because method `foo` is `async`
    = help: consider moving `foo` to another trait
 
-error[E0307]: invalid `self` parameter type: &dyn Foo
+error[E0307]: invalid `self` parameter type: `&dyn Foo`
   --> $DIR/inference_var_self_argument.rs:5:24
    |
 LL |     async fn foo(self: &dyn Foo) {

tests/ui/async-await/issue-66312.stderr

@@ -4,7 +4,7 @@ error[E0308]: mismatched types
 LL |     if x.is_some() {
    |        ^^^^^^^^^^^ expected `bool`, found `()`
 
-error[E0307]: invalid `self` parameter type: T
+error[E0307]: invalid `self` parameter type: `T`
   --> $DIR/issue-66312.rs:4:22
    |
 LL |     fn is_some(self: T);

tests/ui/feature-gates/feature-gate-dispatch-from-dyn-cell.rs

@@ -3,7 +3,7 @@
 use std::cell::Cell;
 
 trait Trait{
-    fn cell(self: Cell<&Self>); //~ ERROR invalid `self` parameter type: Cell<&Self>
+    fn cell(self: Cell<&Self>); //~ ERROR invalid `self` parameter type: `Cell<&Self>`
 }
 
 fn main() {}

tests/ui/feature-gates/feature-gate-dispatch-from-dyn-cell.stderr

@@ -1,4 +1,4 @@
-error[E0307]: invalid `self` parameter type: Cell<&Self>
+error[E0307]: invalid `self` parameter type: `Cell<&Self>`
   --> $DIR/feature-gate-dispatch-from-dyn-cell.rs:6:19
    |
 LL |     fn cell(self: Cell<&Self>);

tests/ui/issues/issue-56806.stderr

@@ -1,4 +1,4 @@
-error[E0307]: invalid `self` parameter type: Box<(dyn Trait + 'static)>
+error[E0307]: invalid `self` parameter type: `Box<(dyn Trait + 'static)>`
   --> $DIR/issue-56806.rs:2:34
    |
 LL |     fn dyn_instead_of_self(self: Box<dyn Trait>);

tests/ui/self/arbitrary-self-opaque.rs

@@ -6,7 +6,7 @@ type Bar = impl Sized;
 
 impl Foo {
     fn foo(self: Bar) {}
-    //~^ ERROR: invalid `self` parameter type: Bar
+    //~^ ERROR: invalid `self` parameter type: `Bar`
 }
 
 fn main() {}

tests/ui/self/arbitrary-self-opaque.stderr

@@ -6,7 +6,7 @@ LL | type Bar = impl Sized;
    |
    = note: `Bar` must be used in combination with a concrete type within the same module
 
-error[E0307]: invalid `self` parameter type: Bar
+error[E0307]: invalid `self` parameter type: `Bar`
   --> $DIR/arbitrary-self-opaque.rs:8:18
    |
 LL |     fn foo(self: Bar) {}

tests/ui/span/issue-27522.stderr

@@ -1,4 +1,4 @@
-error[E0307]: invalid `self` parameter type: &SomeType
+error[E0307]: invalid `self` parameter type: `&SomeType`
   --> $DIR/issue-27522.rs:6:22
    |
 LL |     fn handler(self: &SomeType);

tests/ui/suggestions/object-unsafe-trait-should-use-where-sized.stderr

@@ -26,7 +26,7 @@ help: consider changing method `bar`'s `self` parameter to be `&self`
 LL |     fn bar(self: &Self) {}
    |                  ~~~~~
 
-error[E0307]: invalid `self` parameter type: ()
+error[E0307]: invalid `self` parameter type: `()`
   --> $DIR/object-unsafe-trait-should-use-where-sized.rs:6:18
    |
 LL |     fn bar(self: ()) {}

tests/ui/traits/issue-78372.rs

@@ -6,7 +6,7 @@ impl<T> DispatchFromDyn<Smaht<U, MISC>> for T {} //~ ERROR cannot find type `U`
 //~| ERROR the trait `DispatchFromDyn` may only be implemented for a coercion between structures
 trait Foo: X<u32> {}
 trait X<T> {
-    fn foo(self: Smaht<Self, T>); //~ ERROR: invalid `self`
+    fn foo(self: Smaht<Self, T>); //~ ERROR: invalid `self` parameter type
 }
 trait Marker {}
 impl Marker for dyn Foo {}

tests/ui/traits/issue-78372.stderr

@@ -79,7 +79,7 @@ LL | trait X<T> {
 LL |     fn foo(self: Smaht<Self, T>);
    |                  ^^^^^^^^^^^^^^ ...because method `foo`'s `self` parameter cannot be dispatched on
 
-error[E0307]: invalid `self` parameter type: Smaht<Self, T>
+error[E0307]: invalid `self` parameter type: `Smaht<Self, T>`
   --> $DIR/issue-78372.rs:9:18
    |
 LL |     fn foo(self: Smaht<Self, T>);

tests/ui/ufcs/ufcs-explicit-self-bad.stderr

@@ -15,7 +15,7 @@ LL |     fn dummy2(&self);
    = note: expected signature `fn(&&'a Bar<_>)`
               found signature `fn(&Bar<_>)`
 
-error[E0307]: invalid `self` parameter type: isize
+error[E0307]: invalid `self` parameter type: `isize`
   --> $DIR/ufcs-explicit-self-bad.rs:8:18
    |
 LL |     fn foo(self: isize, x: isize) -> isize {
@@ -24,7 +24,7 @@ LL |     fn foo(self: isize, x: isize) -> isize {
    = note: type of `self` must be `Self` or a type that dereferences to it
    = help: consider changing to `self`, `&self`, `&mut self`, `self: Box<Self>`, `self: Rc<Self>`, `self: Arc<Self>`, or `self: Pin<P>` (where P is one of the previous types except `Self`)
 
-error[E0307]: invalid `self` parameter type: Bar<isize>
+error[E0307]: invalid `self` parameter type: `Bar<isize>`
   --> $DIR/ufcs-explicit-self-bad.rs:19:18
    |
 LL |     fn foo(self: Bar<isize>, x: isize) -> isize {
@@ -33,7 +33,7 @@ LL |     fn foo(self: Bar<isize>, x: isize) -> isize {
    = note: type of `self` must be `Self` or a type that dereferences to it
    = help: consider changing to `self`, `&self`, `&mut self`, `self: Box<Self>`, `self: Rc<Self>`, `self: Arc<Self>`, or `self: Pin<P>` (where P is one of the previous types except `Self`)
 
-error[E0307]: invalid `self` parameter type: &Bar<usize>
+error[E0307]: invalid `self` parameter type: `&Bar<usize>`
   --> $DIR/ufcs-explicit-self-bad.rs:23:18
    |
 LL |     fn bar(self: &Bar<usize>, x: isize) -> isize {