Auto merge of #9276 - dswij:9164, r=flip1995

Ignore `match_like_matches_macro` when there is comment Closes #9164 changelog: [`match_like_matches_macro`] is ignored when there is some comment inside the match block. Also add `span_contains_comment` util to check if given span contains comments.

Author: bors

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();

clippy_utils/src/lib.rs

@@ -87,6 +87,7 @@ use rustc_hir::{
  Mutability, Node, Param, Pat, PatKind, Path, PathSegment, PrimTy, QPath, Stmt, StmtKind, TraitItem, TraitItemKind,
  TraitRef, TyKind, UnOp,
 };
+use rustc_lexer::{tokenize, TokenKind};
 use rustc_lint::{LateContext, Level, Lint, LintContext};
 use rustc_middle::hir::place::PlaceBase;
 use rustc_middle::ty as rustc_ty;
@@ -104,6 +105,7 @@ use rustc_semver::RustcVersion;
 use rustc_session::Session;
 use rustc_span::hygiene::{ExpnKind, MacroKind};
 use rustc_span::source_map::original_sp;
+use rustc_span::source_map::SourceMap;
 use rustc_span::sym;
 use rustc_span::symbol::{kw, Symbol};
 use rustc_span::{Span, DUMMY_SP};
@@ -2278,6 +2280,18 @@ pub fn walk_to_expr_usage<'tcx, T>(
  None
 }
 
+/// Checks whether a given span has any comment token
+/// This checks for all types of comment: line "//", block "/**", doc "///" "//!"
+pub fn span_contains_comment(sm: &SourceMap, span: Span) -> bool {
+ let Ok(snippet) = sm.span_to_snippet(span) else { return false };
+ return tokenize(&snippet).any(|token| {
+ matches!(
+ token.kind,
+ TokenKind::BlockComment { .. } | TokenKind::LineComment { .. }
+ )
+ });
+}
+
 macro_rules! op_utils {
  ($($name:ident $assign:ident)*) => {
  /// Binary operation traits like `LangItem::Add`

tests/ui/match_expr_like_matches_macro.fixed

@@ -167,4 +167,29 @@ fn main() {
  _ => false,
  };
  }
+
+ let x = ' ';
+ // ignore if match block contains comment
+ let _line_comments = match x {
+ // numbers are bad!
+ '1' | '2' | '3' => true,
+ // spaces are very important to be true.
+ ' ' => true,
+ // as are dots
+ '.' => true,
+ _ => false,
+ };
+
+ let _block_comments = match x {
+ /* numbers are bad!
+ */
+ '1' | '2' | '3' => true,
+ /* spaces are very important to be true.
+ */
+ ' ' => true,
+ /* as are dots
+ */
+ '.' => true,
+ _ => false,
+ };
 }

tests/ui/match_expr_like_matches_macro.rs

@@ -208,4 +208,29 @@ fn main() {
  _ => false,
  };
  }
+
+ let x = ' ';
+ // ignore if match block contains comment
+ let _line_comments = match x {
+ // numbers are bad!
+ '1' | '2' | '3' => true,
+ // spaces are very important to be true.
+ ' ' => true,
+ // as are dots
+ '.' => true,
+ _ => false,
+ };
+
+ let _block_comments = match x {
+ /* numbers are bad!
+ */
+ '1' | '2' | '3' => true,
+ /* spaces are very important to be true.
+ */
+ ' ' => true,
+ /* as are dots
+ */
+ '.' => true,
+ _ => false,
+ };
 }