Rollup merge of rust-lang#118727 - compiler-errors:lint-decorate, r=WaffleLapkin

Don't pass lint back out of lint decorator

Change the decorator function in the signature of the `emit_lint`/`span_lint`/etc family of methods from `impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>) -> &'b mut DiagnosticBuilder<'a, ()>` to `impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>)`. I consider it easier to read this way, especially when there's control flow involved.

r? nnethercote though feel free to reassign

Author: workingjubilee

clippy_utils/src/diagnostics.rs

@@ -49,7 +49,6 @@ pub fn span_lint<T: LintContext>(cx: &T, lint: &'static Lint, sp: impl Into<Mult
     #[expect(clippy::disallowed_methods)]
     cx.struct_span_lint(lint, sp, msg.to_string(), |diag| {
         docs_link(diag, lint);
-        diag
     });
 }
 
@@ -90,7 +89,6 @@ pub fn span_lint_and_help<T: LintContext>(
             diag.help(help.to_string());
         }
         docs_link(diag, lint);
-        diag
     });
 }
 
@@ -134,7 +132,6 @@ pub fn span_lint_and_note<T: LintContext>(
             diag.note(note);
         }
         docs_link(diag, lint);
-        diag
     });
 }
 
@@ -152,15 +149,13 @@ where
     cx.struct_span_lint(lint, sp, msg.to_string(), |diag| {
         f(diag);
         docs_link(diag, lint);
-        diag
     });
 }
 
 pub fn span_lint_hir(cx: &LateContext<'_>, lint: &'static Lint, hir_id: HirId, sp: Span, msg: &str) {
     #[expect(clippy::disallowed_methods)]
     cx.tcx.struct_span_lint_hir(lint, hir_id, sp, msg.to_string(), |diag| {
         docs_link(diag, lint);
-        diag
     });
 }
 
@@ -176,7 +171,6 @@ pub fn span_lint_hir_and_then(
     cx.tcx.struct_span_lint_hir(lint, hir_id, sp, msg.to_string(), |diag| {
         f(diag);
         docs_link(diag, lint);
-        diag
     });
 }