objective-c++11: extend c++11 range-based loop to iterate
over objective-c container collection. // rdar://9293227


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159847 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index 31d3680..2db8b5d 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -1634,6 +1634,11 @@
 
 }
 
+static bool ObjCEnumerationCollection(Expr *Collection) {
+  return !Collection->isTypeDependent()
+          && Collection->getType()->getAs<ObjCObjectPointerType>() != 0;
+}
+
 /// ActOnCXXForRangeStmt - Check and build a C++0x for-range statement.
 ///
 /// C++0x [stmt.ranged]:
@@ -1658,6 +1663,10 @@
                            SourceLocation RParenLoc) {
   if (!First || !Range)
     return StmtError();
+  
+  if (ObjCEnumerationCollection(Range))
+    return ActOnObjCForCollectionStmt(ForLoc, LParenLoc, First, Range,
+                                      RParenLoc);
 
   DeclStmt *DS = dyn_cast<DeclStmt>(First);
   assert(DS && "first part of for range not a decl stmt");
@@ -1928,6 +1937,9 @@
   if (!S || !B)
     return StmtError();
 
+  if (isa<ObjCForCollectionStmt>(S))
+    return FinishObjCForCollectionStmt(S, B);
+  
   CXXForRangeStmt *ForStmt = cast<CXXForRangeStmt>(S);
   ForStmt->setBody(B);
 
diff --git a/test/SemaObjCXX/foreach.mm b/test/SemaObjCXX/foreach.mm
new file mode 100644
index 0000000..3c4b908
--- /dev/null
+++ b/test/SemaObjCXX/foreach.mm
@@ -0,0 +1,61 @@
+// RUN: %clang_cc1 -fsyntax-only -fblocks -verify -std=c++11 %s
+// rdar://9293227
+
+@class NSArray;
+
+void f(NSArray *a) {
+    id keys;
+    for (int i : a); // expected-error{{selector element type 'int' is not a valid object}} 
+    for ((id)2 : a);  // expected-error {{for range declaration must declare a variable}} \
+                      // expected-warning {{expression result unused}}
+    for (2 : a); // expected-error {{for range declaration must declare a variable}} \
+                 // expected-warning {{expression result unused}}
+  
+  for (id thisKey : keys);
+}
+
+/* // rdar://9072298 */
+@protocol NSObject @end
+
+@interface NSObject <NSObject> {
+    Class isa;
+}
+@end
+
+typedef struct {
+    unsigned long state;
+    id *itemsPtr;
+    unsigned long *mutationsPtr;
+    unsigned long extra[5];
+} NSFastEnumerationState;
+
+@protocol NSFastEnumeration
+
+- (unsigned long)countByEnumeratingWithState:(NSFastEnumerationState *)state objects:(id *)stackbuf count:(unsigned long)len;
+
+@end
+
+int main ()
+{
+ NSObject<NSFastEnumeration>* collection = 0;
+ for (id thing : collection) { }
+
+ id array;
+ for (int (^b)(void) : array) {
+    if (b() == 10000) {
+        return 1;
+    }
+ }
+ return 0;
+}
+
+/* rdar://problem/11068137 */
+@interface Test2
+@property (assign) id prop;
+@end
+void test2(NSObject<NSFastEnumeration> *collection) {
+  Test2 *obj;
+  for (obj.prop : collection) { // expected-error {{for range declaration must declare a variable}} \
+                                // expected-warning {{property access result unused - getters should not be used for side effects}}
+  }
+}