[clang-format] Fix a misannotation of redundant r_paren as CastRParen (#105921)

Fixes #105880.

Author: owenca

clang/lib/Format/TokenAnnotator.cpp

@@ -2875,6 +2875,8 @@ class AnnotatingParser {
     // Search for unexpected tokens.
     for (auto *Prev = BeforeRParen; Prev != LParen; Prev = Prev->Previous) {
       if (Prev->is(tok::r_paren)) {
+        if (Prev->is(TT_CastRParen))
+          return false;
         Prev = Prev->MatchingParen;
         if (!Prev)
           return false;

clang/unittests/Format/TokenAnnotatorTest.cpp

@@ -747,6 +747,12 @@ TEST_F(TokenAnnotatorTest, UnderstandsCasts) {
   EXPECT_TOKEN(Tokens[9], tok::r_paren, TT_CastRParen);
   EXPECT_TOKEN(Tokens[10], tok::amp, TT_UnaryOperator);
 
+  Tokens = annotate("int result = ((int)a) - b;");
+  ASSERT_EQ(Tokens.size(), 13u) << Tokens;
+  EXPECT_TOKEN(Tokens[6], tok::r_paren, TT_CastRParen);
+  EXPECT_TOKEN(Tokens[8], tok::r_paren, TT_Unknown);
+  EXPECT_TOKEN(Tokens[9], tok::minus, TT_BinaryOperator);
+
   auto Style = getLLVMStyle();
   Style.TypeNames.push_back("Foo");
   Tokens = annotate("#define FOO(bar) foo((Foo)&bar)", Style);