Implement some suggestions by Daniel:

-Change Parser::ParseCXXScopeSpecifier to MaybeParseCXXScopeSpecifier
-Remove Parser::isTokenCXXScopeSpecifier and fold it into MaybeParseCXXScopeSpecifier
-Rename Parser::TryAnnotateScopeToken to TryAnnotateCXXScopeToken and only allow it to be called when in C++

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@60117 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Parse/Parser.h

@@ -118,17 +118,6 @@ private:
            Tok.getKind() == tok::wide_string_literal;
   }
 
-  /// isTokenCXXScopeSpecifier - True if this token is '::', or identifier with
-  /// '::' as next token, or a 'C++ scope annotation' token.
-  /// When not in C++, always returns false.
-  ///
-  bool isTokenCXXScopeSpecifier() {
-    return getLang().CPlusPlus &&
-           (Tok.is(tok::coloncolon)     ||
-            Tok.is(tok::annot_cxxscope) ||
-            (Tok.is(tok::identifier) && NextToken().is(tok::coloncolon)));
-  }
-
   /// ConsumeToken - Consume the current 'peek token' and lex the next one.
   /// This does not work with all kinds of tokens: strings and specific other
   /// tokens must be consumed with custom methods below.  This returns the
@@ -239,9 +228,9 @@ private:
   /// typenames.
   void TryAnnotateTypeOrScopeToken();
 
-  /// TryAnnotateScopeToken - Like TryAnnotateTypeOrScopeToken but only
+  /// TryAnnotateCXXScopeToken - Like TryAnnotateTypeOrScopeToken but only
   /// annotates C++ scope specifiers.
-  void TryAnnotateScopeToken();
+  void TryAnnotateCXXScopeToken();
 
   /// TentativeParsingAction - An object that is used as a kind of "tentative
   /// parsing transaction". It gets instantiated to mark the token position and
@@ -476,7 +465,10 @@ private:
   //===--------------------------------------------------------------------===//
   // C++ Expressions
   ExprResult ParseCXXIdExpression();
-  void ParseCXXScopeSpecifier(CXXScopeSpec &SS);
+
+  /// MaybeParseCXXScopeSpecifier - Parse global scope or nested-name-specifier.
+  /// Returns true if a nested-name-specifier was parsed from the token stream.
+  bool MaybeParseCXXScopeSpecifier(CXXScopeSpec &SS);
   
   //===--------------------------------------------------------------------===//
   // C++ 5.2p1: C++ Casts

lib/Parse/ParseDecl.cpp

@@ -427,7 +427,7 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS) {
     // Only annotate C++ scope. Allow class-name as an identifier in case
     // it's a constructor.
     if (getLang().CPlusPlus)
-      TryAnnotateScopeToken();
+      TryAnnotateCXXScopeToken();
     
     switch (Tok.getKind()) {
     default: 
@@ -985,8 +985,7 @@ void Parser::ParseEnumSpecifier(DeclSpec &DS) {
     Attr = ParseAttributes();
 
   CXXScopeSpec SS;
-  if (isTokenCXXScopeSpecifier()) {
-    ParseCXXScopeSpecifier(SS);
+  if (getLang().CPlusPlus && MaybeParseCXXScopeSpecifier(SS)) {
     if (Tok.isNot(tok::identifier)) {
       Diag(Tok, diag::err_expected_ident);
       if (Tok.isNot(tok::l_brace)) {
@@ -1435,8 +1434,8 @@ void Parser::ParseDirectDeclarator(Declarator &D) {
   CXXScopeSpec &SS = D.getCXXScopeSpec();
   DeclaratorScopeObj DeclScopeObj(*this, SS);
 
-  if (D.mayHaveIdentifier() && isTokenCXXScopeSpecifier()) {
-    ParseCXXScopeSpecifier(SS);
+  if (D.mayHaveIdentifier() &&
+      getLang().CPlusPlus && MaybeParseCXXScopeSpecifier(SS)) {
     // Change the declaration context for name lookup, until this function is
     // exited (and the declarator has been parsed).
     DeclScopeObj.EnterDeclaratorScope();

lib/Parse/ParseDeclCXX.cpp

@@ -218,8 +218,7 @@ void Parser::ParseClassSpecifier(DeclSpec &DS) {
 
   // Parse the (optional) nested-name-specifier.
   CXXScopeSpec SS;
-  if (isTokenCXXScopeSpecifier()) {
-    ParseCXXScopeSpecifier(SS);
+  if (getLang().CPlusPlus && MaybeParseCXXScopeSpecifier(SS)) {
     if (Tok.isNot(tok::identifier))
       Diag(Tok, diag::err_expected_ident);
   }
@@ -362,8 +361,7 @@ Parser::BaseResult Parser::ParseBaseSpecifier(DeclTy *ClassDecl)
 
   // Parse optional '::' and optional nested-name-specifier.
   CXXScopeSpec SS;
-  if (isTokenCXXScopeSpecifier())
-    ParseCXXScopeSpecifier(SS);
+  MaybeParseCXXScopeSpecifier(SS);
 
   // The location of the base class itself.
   SourceLocation BaseLoc = Tok.getLocation();

lib/Parse/ParseExprCXX.cpp

@@ -17,7 +17,8 @@
 #include "AstGuard.h"
 using namespace clang;
 
-/// ParseCXXScopeSpecifier - Parse global scope or nested-name-specifier.
+/// MaybeParseCXXScopeSpecifier - Parse global scope or nested-name-specifier.
+/// Returns true if a nested-name-specifier was parsed from the token stream.
 ///
 ///       '::'[opt] nested-name-specifier
 ///       '::'
@@ -28,14 +29,20 @@ using namespace clang;
 ///         nested-name-specifier identifier '::'
 ///         nested-name-specifier 'template'[opt] simple-template-id '::' [TODO]
 ///
-void Parser::ParseCXXScopeSpecifier(CXXScopeSpec &SS) {
-  assert(isTokenCXXScopeSpecifier() && "Not scope specifier!");
+bool Parser::MaybeParseCXXScopeSpecifier(CXXScopeSpec &SS) {
+  assert(getLang().CPlusPlus &&
+         "Call sites of this function should be guarded by checking for C++.");
+
+  if (Tok.isNot(tok::coloncolon)     &&
+      Tok.isNot(tok::annot_cxxscope) &&
+      (Tok.isNot(tok::identifier) || NextToken().isNot(tok::coloncolon)))
+    return false;
 
   if (Tok.is(tok::annot_cxxscope)) {
     SS.setScopeRep(Tok.getAnnotationValue());
     SS.setRange(Tok.getAnnotationRange());
     ConsumeToken();
-    return;
+    return true;
   }
 
   SS.setBeginLoc(Tok.getLocation());
@@ -68,6 +75,8 @@ void Parser::ParseCXXScopeSpecifier(CXXScopeSpec &SS) {
          Actions.ActOnCXXNestedNameSpecifier(CurScope, SS, IdLoc, CCLoc, *II) );
     SS.setEndLoc(CCLoc);
   }
+
+  return true;
 }
 
 /// ParseCXXIdExpression - Handle id-expression.
@@ -126,8 +135,7 @@ Parser::ExprResult Parser::ParseCXXIdExpression() {
   //   '::' unqualified-id
   //
   CXXScopeSpec SS;
-  if (isTokenCXXScopeSpecifier())
-    ParseCXXScopeSpecifier(SS);
+  MaybeParseCXXScopeSpecifier(SS);
 
   // unqualified-id:
   //   identifier

lib/Parse/Parser.cpp

@@ -705,8 +705,8 @@ void Parser::TryAnnotateTypeOrScopeToken() {
     return;
 
   CXXScopeSpec SS;
-  if (isTokenCXXScopeSpecifier())
-    ParseCXXScopeSpecifier(SS);
+  if (getLang().CPlusPlus)
+    MaybeParseCXXScopeSpecifier(SS);
 
   if (Tok.is(tok::identifier)) {
     TypeTy *Ty = Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope, &SS);
@@ -746,13 +746,15 @@ void Parser::TryAnnotateTypeOrScopeToken() {
 
 /// TryAnnotateScopeToken - Like TryAnnotateTypeOrScopeToken but only
 /// annotates C++ scope specifiers.
-void Parser::TryAnnotateScopeToken() {
+void Parser::TryAnnotateCXXScopeToken() {
+  assert(getLang().CPlusPlus &&
+         "Call sites of this function should be guarded by checking for C++.");
+
   if (Tok.is(tok::annot_cxxscope))
     return;
 
-  if (isTokenCXXScopeSpecifier()) {
-    CXXScopeSpec SS;
-    ParseCXXScopeSpecifier(SS);
+  CXXScopeSpec SS;
+  if (MaybeParseCXXScopeSpecifier(SS)) {
 
     // Push the current token back into the token stream (or revert it if it is
     // cached) and use an annotation scope token for current token.