diff options
| -rw-r--r-- | compiler/rustc_lint/src/for_loop_over_fallibles.rs | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/compiler/rustc_lint/src/for_loop_over_fallibles.rs b/compiler/rustc_lint/src/for_loop_over_fallibles.rs index c96c9efe1d8..d765131442f 100644 --- a/compiler/rustc_lint/src/for_loop_over_fallibles.rs +++ b/compiler/rustc_lint/src/for_loop_over_fallibles.rs @@ -1,6 +1,7 @@ use crate::{LateContext, LateLintPass, LintContext}; use hir::{Expr, Pat}; +use rustc_errors::Applicability; use rustc_hir as hir; use rustc_middle::ty; use rustc_span::sym; @@ -65,18 +66,24 @@ impl<'tcx> LateLintPass<'tcx> for ForLoopOverFallibles { _ => return, }; - let Ok(pat_snip) = cx.sess().source_map().span_to_snippet(pat.span) else { return }; let Ok(arg_snip) = cx.sess().source_map().span_to_snippet(arg.span) else { return }; - let help_string = format!( - "consider replacing `for {pat_snip} in {arg_snip}` with `if let {var}({pat_snip}) = {arg_snip}`" - ); let msg = format!( "for loop over `{arg_snip}`, which is {article} `{ty}`. This is more readably written as an `if let` statement", ); cx.struct_span_lint(FOR_LOOP_OVER_FALLIBLES, arg.span, |diag| { - diag.build(msg).help(help_string).emit() + diag.build(msg) + .multipart_suggestion_verbose( + "consider using `if let` to clear intent", + vec![ + // NB can't use `until` here because `expr.span` and `pat.span` have different syntax contexts + (expr.span.with_hi(pat.span.lo()), format!("if let {var}(")), + (pat.span.between(arg.span), format!(") = ")), + ], + Applicability::MachineApplicable, + ) + .emit() }) } } @@ -89,11 +96,10 @@ fn extract_for_loop<'tcx>(expr: &Expr<'tcx>) -> Option<(&'tcx Pat<'tcx>, &'tcx E && let [stmt] = block.stmts && let hir::StmtKind::Expr(e) = stmt.kind && let hir::ExprKind::Match(_, [_, some_arm], _) = e.kind - && let hir::PatKind::Struct(_, [field], _) = some_arm.pat.kind + && let hir::PatKind::Struct(_, [field], _) = some_arm.pat.kind { Some((field.pat, arg)) } else { None } - -} \ No newline at end of file +} |