[clang-format] Handle pointer/reference in macro definitions (#107074)

A macro definition needs its own scope stack in the annotator, so we add
the MacroBodyScopes stack and use ScopeStack to refer to it when in the
macro definition body.

Also, we need to have a scope type for a child block because its parent
line is parsed (and thus the scope type for the braces is popped off the
scope stack) before the lines in the child block are.

Fixes #99271.

Author: owenca

clang/lib/Format/TokenAnnotator.cpp

@@ -137,9 +137,8 @@ class AnnotatingParser {
 private:
   ScopeType getScopeType(const FormatToken &Token) const {
     switch (Token.getType()) {
-    case TT_FunctionLBrace:
     case TT_LambdaLBrace:
-      return ST_Function;
+      return ST_ChildBlock;
     case TT_ClassLBrace:
     case TT_StructLBrace:
     case TT_UnionLBrace:
@@ -400,7 +399,8 @@ class AnnotatingParser {
                OpeningParen.Previous->MatchingParen->isOneOf(
                    TT_ObjCBlockLParen, TT_FunctionTypeLParen)) {
       Contexts.back().IsExpression = false;
-    } else if (!Line.MustBeDeclaration && !Line.InPPDirective) {
+    } else if (!Line.MustBeDeclaration &&
+               (!Line.InPPDirective || (Line.InMacroBody && !Scopes.empty()))) {
       bool IsForOrCatch =
           OpeningParen.Previous &&
           OpeningParen.Previous->isOneOf(tok::kw_for, tok::kw_catch);
@@ -3649,11 +3649,21 @@ static bool isCtorOrDtorName(const FormatToken *Tok) {
 }
 
 void TokenAnnotator::annotate(AnnotatedLine &Line) {
-  AnnotatingParser Parser(Style, Line, Keywords, Scopes);
+  if (!Line.InMacroBody)
+    MacroBodyScopes.clear();
+
+  auto &ScopeStack = Line.InMacroBody ? MacroBodyScopes : Scopes;
+  AnnotatingParser Parser(Style, Line, Keywords, ScopeStack);
   Line.Type = Parser.parseLine();
 
-  for (auto &Child : Line.Children)
-    annotate(*Child);
+  if (!Line.Children.empty()) {
+    ScopeStack.push_back(ST_ChildBlock);
+    for (auto &Child : Line.Children)
+      annotate(*Child);
+    // ScopeStack can become empty if Child has an unmatched `}`.
+    if (!ScopeStack.empty())
+      ScopeStack.pop_back();
+  }
 
   // With very deep nesting, ExpressionParser uses lots of stack and the
   // formatting algorithm is very slow. We're not going to do a good job here
@@ -3671,7 +3681,7 @@ void TokenAnnotator::annotate(AnnotatedLine &Line) {
   if (IsCpp) {
     FormatToken *OpeningParen = nullptr;
     auto *Tok = getFunctionName(Line, OpeningParen);
-    if (Tok && ((!Scopes.empty() && Scopes.back() == ST_Class) ||
+    if (Tok && ((!ScopeStack.empty() && ScopeStack.back() == ST_Class) ||
                 Line.endsWith(TT_FunctionLBrace) || isCtorOrDtorName(Tok))) {
       Tok->setFinalizedType(TT_CtorDtorDeclName);
       assert(OpeningParen);

clang/lib/Format/TokenAnnotator.h

@@ -36,11 +36,11 @@ enum LineType {
 };
 
 enum ScopeType {
+  // Contained in child block.
+  ST_ChildBlock,
   // Contained in class declaration/definition.
   ST_Class,
-  // Contained within function definition.
-  ST_Function,
-  // Contained within other scope block (loop, if/else, etc).
+  // Contained within other scope block (function, loop, if/else, etc).
   ST_Other,
 };
 
@@ -269,7 +269,7 @@ class TokenAnnotator {
 
   const AdditionalKeywords &Keywords;
 
-  SmallVector<ScopeType> Scopes;
+  SmallVector<ScopeType> Scopes, MacroBodyScopes;
 };
 
 } // end namespace format

clang/unittests/Format/TokenAnnotatorTest.cpp

@@ -327,6 +327,21 @@ TEST_F(TokenAnnotatorTest, UnderstandsUsesOfStarAndAmp) {
   ASSERT_EQ(Tokens.size(), 26u) << Tokens;
   EXPECT_TOKEN(Tokens[3], tok::ampamp, TT_BinaryOperator);
   EXPECT_TOKEN(Tokens[16], tok::ampamp, TT_BinaryOperator);
+
+  Tokens = annotate("#define FOO \\\n"
+                    "  void foo() { f(a * b); }");
+  ASSERT_EQ(Tokens.size(), 17u) << Tokens;
+  EXPECT_TOKEN(Tokens[11], tok::star, TT_BinaryOperator);
+
+  Tokens = annotate("#define FOO auto Foo = [] { f(a * b); };");
+  ASSERT_EQ(Tokens.size(), 19u) << Tokens;
+  EXPECT_TOKEN(Tokens[12], tok::star, TT_BinaryOperator);
+
+  Tokens = annotate("namespace {\n"
+                    "#define FOO(x) void foo(a##x *b);\n"
+                    "}");
+  ASSERT_EQ(Tokens.size(), 20u) << Tokens;
+  EXPECT_TOKEN(Tokens[14], tok::star, TT_PointerOrReference);
 }
 
 TEST_F(TokenAnnotatorTest, UnderstandsUsesOfPlusAndMinus) {