[clang-format] Handle function decls with MS calling conventions (#143083)

Author: owenca

clang/lib/Format/TokenAnnotator.cpp

@@ -1769,7 +1769,15 @@ class AnnotatingParser {
                        Keywords.kw___has_include_next)) {
         parseHasInclude();
       }
-      if (Style.isCSharp()) {
+      if (IsCpp) {
+        if (Next && Next->is(tok::l_paren) && Prev &&
+            Prev->isOneOf(tok::kw___cdecl, tok::kw___stdcall,
+                          tok::kw___fastcall, tok::kw___thiscall,
+                          tok::kw___regcall, tok::kw___vectorcall)) {
+          Tok->setFinalizedType(TT_FunctionDeclarationName);
+          Next->setFinalizedType(TT_FunctionDeclarationLParen);
+        }
+      } else if (Style.isCSharp()) {
         if (Tok->is(Keywords.kw_where) && Next && Next->isNot(tok::l_paren)) {
           Tok->setType(TT_CSharpGenericTypeConstraint);
           parseCSharpGenericTypeConstraint();

clang/unittests/Format/TokenAnnotatorTest.cpp

@@ -2273,6 +2273,11 @@ TEST_F(TokenAnnotatorTest, UnderstandsFunctionDeclarationNames) {
   EXPECT_TOKEN(Tokens[16], tok::l_paren, TT_FunctionDeclarationLParen);
   EXPECT_TOKEN(Tokens[18], tok::arrow, TT_TrailingReturnArrow);
 
+  Tokens = annotate("void __stdcall f();");
+  ASSERT_EQ(Tokens.size(), 7u) << Tokens;
+  EXPECT_TOKEN(Tokens[2], tok::identifier, TT_FunctionDeclarationName);
+  EXPECT_TOKEN(Tokens[3], tok::l_paren, TT_FunctionDeclarationLParen);
+
   Tokens = annotate("int iso_time(time_t);");
   ASSERT_EQ(Tokens.size(), 7u) << Tokens;
   EXPECT_TOKEN(Tokens[1], tok::identifier, TT_FunctionDeclarationName);