release/21.x: [clang-format] Fix a regression in annotating star befo…

[owenca]

…re lambda (#170969)

Backport 4930e94

[llvmbot]

@llvm/pr-subscribers-clang-format

Author: owenca (owenca)

Changes

…re lambda (#170969)

Backport 4930e94

---

Full diff: https://github.com/llvm/llvm-project/pull/170997.diff

2 Files Affected:

• (modified) clang/lib/Format/UnwrappedLineParser.cpp (+4-4)
• (modified) clang/unittests/Format/TokenAnnotatorTest.cpp (+6)

diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index 934605733542f..3df071a197c67 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -2385,17 +2385,17 @@ bool UnwrappedLineParser::tryToParseLambdaIntroducer() {
   const FormatToken *LeftSquare = FormatTok;
   nextToken();
   if (Previous) {
+    const auto *PrevPrev = Previous->getPreviousNonComment();
+    if (Previous->is(tok::star) && PrevPrev && PrevPrev->isTypeName(LangOpts))
+      return false;
     if (Previous->closesScope()) {
       // Not a potential C-style cast.
       if (Previous->isNot(tok::r_paren))
         return false;
-      const auto *BeforeRParen = Previous->getPreviousNonComment();
       // Lambdas can be cast to function types only, e.g. `std::function<int()>`
       // and `int (*)()`.
-      if (!BeforeRParen || !BeforeRParen->isOneOf(tok::greater, tok::r_paren))
+      if (!PrevPrev || !PrevPrev->isOneOf(tok::greater, tok::r_paren))
         return false;
-    } else if (Previous->is(tok::star)) {
-      Previous = Previous->getPreviousNonComment();
     }
     if (Previous && Previous->Tok.getIdentifierInfo() &&
         !Previous->isOneOf(tok::kw_return, tok::kw_co_await, tok::kw_co_yield,
diff --git a/clang/unittests/Format/TokenAnnotatorTest.cpp b/clang/unittests/Format/TokenAnnotatorTest.cpp
index 04dc69180960c..810c716b7a411 100644
--- a/clang/unittests/Format/TokenAnnotatorTest.cpp
+++ b/clang/unittests/Format/TokenAnnotatorTest.cpp
@@ -2248,6 +2248,12 @@ TEST_F(TokenAnnotatorTest, UnderstandsLambdas) {
   EXPECT_TOKEN(Tokens[3], tok::l_square, TT_LambdaLSquare);
   EXPECT_TOKEN(Tokens[5], tok::l_paren, TT_LambdaDefinitionLParen);
   EXPECT_TOKEN(Tokens[10], tok::l_square, TT_ArraySubscriptLSquare);
+
+  Tokens = annotate("foo = bar * [] { return 2; }();");
+  ASSERT_EQ(Tokens.size(), 15u) << Tokens;
+  EXPECT_TOKEN(Tokens[3], tok::star, TT_BinaryOperator);
+  EXPECT_TOKEN(Tokens[4], tok::l_square, TT_LambdaLSquare);
+  EXPECT_TOKEN(Tokens[6], tok::l_brace, TT_LambdaLBrace);
 }
 
 TEST_F(TokenAnnotatorTest, UnderstandsFunctionAnnotations) {

[dyung]

Hi, I just wanted to also caution that this will be the last 21.x release, so any issues that arise from this or other changes will not be fixed until 22.x branches next month.

[github-actions]

@owenca (or anyone else). If you would like to add a note about this fix in the release notes (completely optional). Please reply to this comment with a one or two sentence description of the fix. When you are done, please add the release:note label to this PR.