From e34ba1898e11a709803ff85917f129de4ecca8e5 Mon Sep 17 00:00:00 2001
From: Owen Pan <owenpiano@gmail.com>
Date: Tue, 29 Apr 2025 19:24:39 -0700
Subject: [PATCH] [clang-format] Correctly annotate user-defined conversion
 function call

Fix #137770
---
 clang/lib/Format/TokenAnnotator.cpp           | 13 +++++++++----
 clang/unittests/Format/TokenAnnotatorTest.cpp | 10 ++++++++--
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index e56cc92987af7..ea0086fd49a33 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -1656,11 +1656,15 @@ class AnnotatingParser {
             // Skip to l_paren.
             for (LParen = CurrentToken->Next;
                  LParen && LParen->isNot(tok::l_paren); LParen = LParen->Next) {
+              if (LParen->isPointerOrReference())
+                LParen->setFinalizedType(TT_PointerOrReference);
             }
           }
           if (LParen && LParen->is(tok::l_paren)) {
-            Tok->setFinalizedType(TT_FunctionDeclarationName);
-            LParen->setFinalizedType(TT_FunctionDeclarationLParen);
+            if (!Contexts.back().IsExpression) {
+              Tok->setFinalizedType(TT_FunctionDeclarationName);
+              LParen->setFinalizedType(TT_FunctionDeclarationLParen);
+            }
             break;
           }
         }
@@ -1683,7 +1687,8 @@ class AnnotatingParser {
         if (CurrentToken->is(tok::comma) && Previous->isNot(tok::kw_operator))
           break;
         if (Previous->isOneOf(TT_BinaryOperator, TT_UnaryOperator, tok::comma,
-                              tok::star, tok::arrow, tok::amp, tok::ampamp) ||
+                              tok::arrow) ||
+            Previous->isPointerOrReference() ||
             // User defined literal.
             Previous->TokenText.starts_with("\"\"")) {
           Previous->setType(TT_OverloadedOperator);
@@ -3026,7 +3031,7 @@ class AnnotatingParser {
 
     if (!NextToken ||
         NextToken->isOneOf(tok::arrow, tok::equal, tok::comma, tok::r_paren,
-                           TT_RequiresClause, TT_FunctionDeclarationLParen) ||
+                           TT_RequiresClause) ||
         (NextToken->is(tok::kw_noexcept) && !IsExpression) ||
         NextToken->canBePointerOrReferenceQualifier() ||
         (NextToken->is(tok::l_brace) && !NextToken->getNextNonComment())) {
diff --git a/clang/unittests/Format/TokenAnnotatorTest.cpp b/clang/unittests/Format/TokenAnnotatorTest.cpp
index 844f51f9e7c2e..124fb43dcf5ac 100644
--- a/clang/unittests/Format/TokenAnnotatorTest.cpp
+++ b/clang/unittests/Format/TokenAnnotatorTest.cpp
@@ -392,9 +392,15 @@ TEST_F(TokenAnnotatorTest, UnderstandsUsesOfStarAndAmp) {
 
   Tokens = annotate("return s.operator int *();");
   ASSERT_EQ(Tokens.size(), 10u) << Tokens;
-  EXPECT_TOKEN(Tokens[3], tok::kw_operator, TT_FunctionDeclarationName);
+  // Not TT_FunctionDeclarationName.
+  EXPECT_TOKEN(Tokens[3], tok::kw_operator, TT_Unknown);
   EXPECT_TOKEN(Tokens[5], tok::star, TT_PointerOrReference);
-  EXPECT_TOKEN(Tokens[6], tok::l_paren, TT_FunctionDeclarationLParen);
+  // Not TT_FunctionDeclarationLParen.
+  EXPECT_TOKEN(Tokens[6], tok::l_paren, TT_Unknown);
+
+  Tokens = annotate("B &b = x.operator B &();");
+  ASSERT_EQ(Tokens.size(), 13u) << Tokens;
+  EXPECT_TOKEN(Tokens[8], tok::amp, TT_PointerOrReference);
 
   Tokens = annotate("int8_t *a = MacroCall(int8_t, width * height * length);");
   ASSERT_EQ(Tokens.size(), 16u) << Tokens;