Implement bracket insertion for Objective-C instance message sends as

part of parser recovery. For example, given:

  a method1:arg];

we detect after parsing the expression "a" that we have the start of a
message send expression. We pretend we've seen a '[' prior to the a,
then parse the remainder as a message send. We'll then give a
diagnostic+fix-it such as:

fixit-objc-message.m:17:3: error: missing '[' at start of message
      send expression
  a method1:arg];
  ^
  [

The algorithm here is very simple, and always assumes that the open
bracket goes at the beginning of the message send. It also only works
for non-super instance message sends at this time.

llvm-svn: 113968

1 files changed, 7 insertions, 1 deletions

diff --git a/clang/lib/Parse/ParseInit.cpp b/clang/lib/Parse/ParseInit.cpp
index 4347294141a..c2675f33e78 100644
--- a/clang/lib/Parse/ParseInit.cpp
+++ b/clang/lib/Parse/ParseInit.cpp
@@ -13,6 +13,7 @@
 
 #include "clang/Parse/Parser.h"
 #include "clang/Parse/ParseDiagnostic.h"
+#include "RAIIObjectsForParser.h"
 #include "clang/Sema/Designator.h"
 #include "clang/Sema/Scope.h"
 #include "llvm/ADT/SmallString.h"
@@ -136,6 +137,8 @@ ExprResult Parser::ParseInitializerWithPotentialDesignator() {
     //   [foo ... bar]     -> array designator
     //   [4][foo bar]      -> obsolete GNU designation with objc message send.
     //
+    InMessageExpressionRAIIObject InMessage(*this, true);
+    
     SourceLocation StartLoc = ConsumeBracket();
     ExprResult Idx;
 
@@ -146,7 +149,8 @@ ExprResult Parser::ParseInitializerWithPotentialDesignator() {
     if  (getLang().ObjC1 && getLang().CPlusPlus) {
       // Send to 'super'.
       if (Tok.is(tok::identifier) && Tok.getIdentifierInfo() == Ident_super &&
-          NextToken().isNot(tok::period) && getCurScope()->isInObjcMethodScope()) {
+          NextToken().isNot(tok::period) && 
+          getCurScope()->isInObjcMethodScope()) {
         CheckArrayDesignatorSyntax(*this, StartLoc, Desig);
         return ParseAssignmentExprWithObjCMessageExprStart(StartLoc,
                                                            ConsumeToken(),
@@ -310,6 +314,8 @@ ExprResult Parser::ParseInitializerWithPotentialDesignator() {
 ///         initializer-list ',' designation[opt] initializer
 ///
 ExprResult Parser::ParseBraceInitializer() {
+  InMessageExpressionRAIIObject InMessage(*this, false);
+  
   SourceLocation LBraceLoc = ConsumeBrace();
 
   /// InitExprs - This is the actual list of expressions contained in the