migrate: unused.rs

compiler/rustc_lint/src/lints.rs

@@ -1,7 +1,11 @@
-use rustc_errors::{fluent, AddSubdiagnostic, DecorateLint, EmissionGuarantee};
+use rustc_errors::{fluent, AddSubdiagnostic, Applicability, DecorateLint, EmissionGuarantee};
+use rustc_hir::def_id::DefId;
 use rustc_macros::{LintDiagnostic, SessionSubdiagnostic};
+use rustc_middle::ty::Ty;
 use rustc_span::{Span, Symbol};
 
+use crate::LateContext;
+
 #[derive(LintDiagnostic)]
 #[diag(lint_range_endpoint_out_of_range)]
 pub struct RangeEndpointOutOfRange<'a> {
@@ -146,3 +150,130 @@ pub struct InvalidAtomicOrderingDiag {
     #[label]
     pub fail_order_arg_span: Span,
 }
+
+#[derive(LintDiagnostic)]
+#[diag(lint_unused_op)]
+pub struct UnusedOp<'a> {
+    pub op: &'a str,
+    #[label]
+    pub label: Span,
+    #[suggestion(style = "verbose", code = "let _ = ", applicability = "machine-applicable")]
+    pub suggestion: Span,
+}
+
+#[derive(LintDiagnostic)]
+#[diag(lint_unused_result)]
+pub struct UnusedResult<'a> {
+    pub ty: Ty<'a>,
+}
+
+// FIXME(davidtwco): this isn't properly translatable becauses of the
+// pre/post strings
+#[derive(LintDiagnostic)]
+#[diag(lint_unused_closure)]
+#[note]
+pub struct UnusedClosure<'a> {
+    pub count: usize,
+    pub pre: &'a str,
+    pub post: &'a str,
+}
+
+// FIXME(davidtwco): this isn't properly translatable becauses of the
+// pre/post strings
+#[derive(LintDiagnostic)]
+#[diag(lint_unused_generator)]
+#[note]
+pub struct UnusedGenerator<'a> {
+    pub count: usize,
+    pub pre: &'a str,
+    pub post: &'a str,
+}
+
+// FIXME(davidtwco): this isn't properly translatable becauses of the pre/post
+// strings
+pub struct UnusedDef<'a, 'b> {
+    pub pre: &'a str,
+    pub post: &'a str,
+    pub cx: &'a LateContext<'b>,
+    pub def_id: DefId,
+    pub note: Option<Symbol>,
+}
+
+// FIXME: refactor with `Option<String>` in macro
+impl<'a, 'b, G: EmissionGuarantee> DecorateLint<'_, G> for UnusedDef<'a, 'b> {
+    fn decorate_lint(self, diag: rustc_errors::LintDiagnosticBuilder<'_, G>) {
+        let mut diag = diag.build(fluent::lint_unused_def);
+        diag.set_arg("pre", self.pre);
+        diag.set_arg("post", self.post);
+        diag.set_arg("def", self.cx.tcx.def_path_str(self.def_id));
+        // check for #[must_use = "..."]
+        if let Some(note) = self.note {
+            diag.note(note.as_str());
+        }
+        diag.emit();
+    }
+}
+
+#[derive(LintDiagnostic)]
+#[diag(lint_path_statement_drop)]
+pub struct PathStatementDrop {
+    #[subdiagnostic]
+    pub sub: PathStatementDropSub,
+}
+
+#[derive(SessionSubdiagnostic)]
+pub enum PathStatementDropSub {
+    #[suggestion(
+        suggestion,
+        code = "drop({snippet});",
+        applicability = "machine-applicable"
+    )]
+    Suggestion {
+        #[primary_span]
+        span: Span,
+        snippet: String,
+    },
+    #[help(help)]
+    Help {
+        #[primary_span]
+        span: Span,
+    },
+}
+
+#[derive(LintDiagnostic)]
+#[diag(lint_path_statement_no_effect)]
+pub struct PathStatementNoEffect;
+
+#[derive(LintDiagnostic)]
+#[diag(lint_unused_delim)]
+pub struct UnusedDelim<'a> {
+    pub delim: &'static str,
+    pub item: &'a str,
+    #[subdiagnostic]
+    pub suggestion: Option<UnusedDelimSuggestion>,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(suggestion, applicability = "machine-applicable")]
+pub struct UnusedDelimSuggestion {
+    #[suggestion_part(code = "{start_replace}")]
+    pub start_span: Span,
+    pub start_replace: &'static str,
+    #[suggestion_part(code = "{end_replace}")]
+    pub end_span: Span,
+    pub end_replace: &'static str,
+}
+
+#[derive(LintDiagnostic)]
+#[diag(lint_unused_import_braces)]
+pub struct UnusedImportBracesDiag {
+    pub node: Symbol,
+}
+
+#[derive(LintDiagnostic)]
+#[diag(lint_unused_allocation)]
+pub struct UnusedAllocationDiag;
+
+#[derive(LintDiagnostic)]
+#[diag(lint_unused_allocation_mut)]
+pub struct UnusedAllocationMutDiag;

compiler/rustc_lint/src/unused.rs

@@ -1,9 +1,16 @@
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
+use crate::lints::{
+    PathStatementDrop, PathStatementDropSub, PathStatementNoEffect, UnusedAllocationDiag,
+    UnusedAllocationMutDiag, UnusedClosure, UnusedDef, UnusedDelim, UnusedDelimSuggestion,
+    UnusedGenerator, UnusedImportBracesDiag, UnusedOp, UnusedResult,
+};
 use crate::Lint;
 use crate::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
 use rustc_ast as ast;
 use rustc_ast::util::{classify, parser};
 use rustc_ast::{ExprKind, StmtKind};
-use rustc_errors::{fluent, pluralize, Applicability, MultiSpan};
+use rustc_errors::{pluralize, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
@@ -163,23 +170,20 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
         let mut op_warned = false;
 
         if let Some(must_use_op) = must_use_op {
-            cx.struct_span_lint(UNUSED_MUST_USE, expr.span, fluent::lint_unused_op, |lint| {
+            cx.emit_spanned_lint(
-                lint.set_arg("op", must_use_op)
+                UNUSED_MUST_USE,
-                    .span_label(expr.span, fluent::label)
+                expr.span,
-                    .span_suggestion_verbose(
+                UnusedOp {
-                        expr.span.shrink_to_lo(),
+                    op: must_use_op,
-                        fluent::suggestion,
+                    label: expr.span,
-                        "let _ = ",
+                    suggestion: expr.span.shrink_to_lo(),
-                        Applicability::MachineApplicable,
+                },
-                    )
+            );
-            });
             op_warned = true;
         }
 
         if !(type_lint_emitted_or_suppressed || fn_warned || op_warned) {
-            cx.struct_span_lint(UNUSED_RESULTS, s.span, fluent::lint_unused_result, |lint| {
+            cx.emit_spanned_lint(UNUSED_RESULTS, s.span, UnusedResult { ty });
-                lint.set_arg("ty", ty)
-            });
         }
 
         fn check_fn_must_use(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> bool {
@@ -402,47 +406,31 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
                     );
                 }
                 MustUsePath::Closure(span) => {
-                    cx.struct_span_lint(
+                    cx.emit_spanned_lint(
                         UNUSED_MUST_USE,
                         *span,
-                        fluent::lint_unused_closure,
+                        UnusedClosure { count: plural_len, pre: descr_pre, post: descr_post },
-                        |lint| {
-                            // FIXME(davidtwco): this isn't properly translatable because of the
-                            // pre/post strings
-                            lint.set_arg("count", plural_len)
-                                .set_arg("pre", descr_pre)
-                                .set_arg("post", descr_post)
-                                .note(fluent::note)
-                        },
                     );
                 }
                 MustUsePath::Generator(span) => {
-                    cx.struct_span_lint(
+                    cx.emit_spanned_lint(
                         UNUSED_MUST_USE,
                         *span,
-                        fluent::lint_unused_generator,
+                        UnusedGenerator { count: plural_len, pre: descr_pre, post: descr_post },
-                        |lint| {
-                            // FIXME(davidtwco): this isn't properly translatable because of the
-                            // pre/post strings
-                            lint.set_arg("count", plural_len)
-                                .set_arg("pre", descr_pre)
-                                .set_arg("post", descr_post)
-                                .note(fluent::note)
-                        },
                     );
                 }
                 MustUsePath::Def(span, def_id, reason) => {
-                    cx.struct_span_lint(UNUSED_MUST_USE, *span, fluent::lint_unused_def, |lint| {
+                    cx.emit_spanned_lint(
-                        // FIXME(davidtwco): this isn't properly translatable because of the pre/post
+                        UNUSED_MUST_USE,
-                        // strings
+                        *span,
-                        lint.set_arg("pre", descr_pre);
+                        UnusedDef {
-                        lint.set_arg("post", descr_post);
+                            pre: descr_pre,
-                        lint.set_arg("def", cx.tcx.def_path_str(*def_id));
+                            post: descr_post,
-                        if let Some(note) = reason {
+                            cx,
-                            lint.note(note.as_str());
+                            def_id: *def_id,
-                        }
+                            note: *reason,
-                        lint
+                        },
-                    });
+                    );
                 }
             }
         }
@@ -478,31 +466,15 @@ impl<'tcx> LateLintPass<'tcx> for PathStatements {
             if let hir::ExprKind::Path(_) = expr.kind {
                 let ty = cx.typeck_results().expr_ty(expr);
                 if ty.needs_drop(cx.tcx, cx.param_env) {
-                    cx.struct_span_lint(
+                    let sub = if let Ok(snippet) = cx.sess().source_map().span_to_snippet(expr.span)
-                        PATH_STATEMENTS,
+                    {
-                        s.span,
+                        PathStatementDropSub::Suggestion { span: s.span, snippet }
-                        fluent::lint_path_statement_drop,
+                    } else {
-                        |lint| {
+                        PathStatementDropSub::Help { span: s.span }
-                            if let Ok(snippet) = cx.sess().source_map().span_to_snippet(expr.span) {
+                    };
-                                lint.span_suggestion(
+                    cx.emit_spanned_lint(PATH_STATEMENTS, s.span, PathStatementDrop { sub })
-                                    s.span,
-                                    fluent::suggestion,
-                                    format!("drop({});", snippet),
-                                    Applicability::MachineApplicable,
-                                );
-                            } else {
-                                lint.span_help(s.span, fluent::suggestion);
-                            }
-                            lint
-                        },
-                    );
                 } else {
-                    cx.struct_span_lint(
+                    cx.emit_spanned_lint(PATH_STATEMENTS, s.span, PathStatementNoEffect);
-                        PATH_STATEMENTS,
-                        s.span,
-                        fluent::lint_path_statement_no_effect,
-                        |lint| lint,
-                    );
                 }
             }
         }
@@ -695,36 +667,35 @@ trait UnusedDelimLint {
         } else {
             MultiSpan::from(value_span)
         };
-        cx.struct_span_lint(self.lint(), primary_span, fluent::lint_unused_delim, |lint| {
+        let suggestion = spans.map(|(lo, hi)| {
-            lint.set_arg("delim", Self::DELIM_STR);
+            let sm = cx.sess().source_map();
-            lint.set_arg("item", msg);
+            let lo_replace =
-            if let Some((lo, hi)) = spans {
-                let sm = cx.sess().source_map();
-                let lo_replace =
                     if keep_space.0 &&
                         let Ok(snip) = sm.span_to_prev_source(lo) && !snip.ends_with(' ') {
-                        " ".to_string()
+                        " "
                         } else {
-                            "".to_string()
+                            ""
                         };
 
-                let hi_replace =
+            let hi_replace =
                     if keep_space.1 &&
                         let Ok(snip) = sm.span_to_next_source(hi) && !snip.starts_with(' ') {
-                        " ".to_string()
+                        " "
                         } else {
-                            "".to_string()
+                            ""
                         };
-
+            UnusedDelimSuggestion {
-                let replacement = vec![(lo, lo_replace), (hi, hi_replace)];
+                start_span: lo,
-                lint.multipart_suggestion(
+                start_replace: lo_replace,
-                    fluent::suggestion,
+                end_span: hi,
-                    replacement,
+                end_replace: hi_replace,
-                    Applicability::MachineApplicable,
-                );
             }
-            lint
         });
+        cx.emit_spanned_lint(
+            self.lint(),
+            primary_span,
+            UnusedDelim { delim: Self::DELIM_STR, item: msg, suggestion },
+        );
     }
 
     fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &ast::Expr) {
@@ -1297,11 +1268,10 @@ impl UnusedImportBraces {
                 ast::UseTreeKind::Nested(_) => return,
             };
 
-            cx.struct_span_lint(
+            cx.emit_spanned_lint(
                 UNUSED_IMPORT_BRACES,
                 item.span,
-                fluent::lint_unused_import_braces,
+                UnusedImportBracesDiag { node: node_name },
-                |lint| lint.set_arg("node", node_name),
             );
         }
     }
@@ -1351,17 +1321,14 @@ impl<'tcx> LateLintPass<'tcx> for UnusedAllocation {
 
         for adj in cx.typeck_results().expr_adjustments(e) {
             if let adjustment::Adjust::Borrow(adjustment::AutoBorrow::Ref(_, m)) = adj.kind {
-                cx.struct_span_lint(
+                match m {
-                    UNUSED_ALLOCATION,
+                    adjustment::AutoBorrowMutability::Not => {
-                    e.span,
+                        cx.emit_spanned_lint(UNUSED_ALLOCATION, e.span, UnusedAllocationDiag);
-                    match m {
+                    }
-                        adjustment::AutoBorrowMutability::Not => fluent::lint_unused_allocation,
+                    adjustment::AutoBorrowMutability::Mut { .. } => {
-                        adjustment::AutoBorrowMutability::Mut { .. } => {
+                        cx.emit_spanned_lint(UNUSED_ALLOCATION, e.span, UnusedAllocationMutDiag);
-                            fluent::lint_unused_allocation_mut
+                    }
-                        }
+                };
-                    },
-                    |lint| lint,
-                );
             }
         }
     }