objective-c: provide a useful 'fixit' suggestion when
errornously using commas to separate ObjC message arguments.
// rdar://11376372


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@157216 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticParseKinds.td b/include/clang/Basic/DiagnosticParseKinds.td
index ccd5074..e251af4 100644
--- a/include/clang/Basic/DiagnosticParseKinds.td
+++ b/include/clang/Basic/DiagnosticParseKinds.td
@@ -378,6 +378,8 @@
 def warn_semicolon_before_method_body : Warning<
   "semicolon before method body is ignored">,
   InGroup<DiagGroup<"semicolon-before-method-body">>, DefaultIgnore;
+def note_extra_comma_message_arg : Note<
+  "comma separating objective-c messaging arguments">;
 
 def err_expected_field_designator : Error<
   "expected a field designator, such as '.field = 4'">;
diff --git a/lib/Parse/ParseObjc.cpp b/lib/Parse/ParseObjc.cpp
index 164c2f4..f7efad5 100644
--- a/lib/Parse/ParseObjc.cpp
+++ b/lib/Parse/ParseObjc.cpp
@@ -2452,10 +2452,14 @@
     }
     // Parse the, optional, argument list, comma separated.
     while (Tok.is(tok::comma)) {
-      ConsumeToken(); // Eat the ','.
+      SourceLocation commaLoc = ConsumeToken(); // Eat the ','.
       ///  Parse the expression after ','
       ExprResult Res(ParseAssignmentExpression());
       if (Res.isInvalid()) {
+        if (Tok.is(tok::colon)) {
+          Diag(commaLoc, diag::note_extra_comma_message_arg) <<
+            FixItHint::CreateRemoval(commaLoc);
+        }
         // We must manually skip to a ']', otherwise the expression skipper will
         // stop at the ']' when it skips to the ';'.  We want it to skip beyond
         // the enclosing expression.
diff --git a/test/FixIt/fixit-objc-message-comma-separator.m b/test/FixIt/fixit-objc-message-comma-separator.m
new file mode 100644
index 0000000..0caa33e
--- /dev/null
+++ b/test/FixIt/fixit-objc-message-comma-separator.m
@@ -0,0 +1,17 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10  -fdiagnostics-parseable-fixits -x objective-c %s 2>&1 | FileCheck %s
+// rdar://11376372
+
+@class NSObject;
+
+@interface TestObj {
+}
+-(void)aMethodWithArg1:(NSObject*)arg1 arg2:(NSObject*)arg2;
+@end
+
+int main(int argc, char *argv[])
+{
+    TestObj *obj;
+    [obj aMethodWithArg1:@"Arg 1 Good", arg2:@"Arg 2 Good"]; 
+}
+
+// CHECK: {14:39-14:40}:""