This adds adds four macros when compiling using GTEST_OS_MAC:
{ASSERT,EXPECT}_NS{NE,EQ}.  These test ObjC objects using |-isEqual:| and
prints failures using the |-description| selector.  This allows for better
debugging output with ObjC++ test cases.

BUG=http://code.google.com/p/googletest/issues/detail?id=303
TEST=Covered by unit tests.

Review URL: http://codereview.chromium.org/3028047

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@55180 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/testing/gtest_mac.mm b/testing/gtest_mac.mm
new file mode 100644
index 0000000..3caacdf
--- /dev/null
+++ b/testing/gtest_mac.mm
@@ -0,0 +1,53 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "gtest_mac.h"
+
+#include <gtest/internal/gtest-port.h>
+#include <gtest/internal/gtest-string.h>
+#include <gtest/gtest.h>
+
+#ifdef GTEST_OS_MAC
+
+#import <Foundation/Foundation.h>
+
+namespace testing {
+namespace internal {
+
+// This overloaded version allows comparison between ObjC objects that conform
+// to the NSObject protocol. Used to implement {ASSERT|EXPECT}_EQ().
+GTEST_API_ AssertionResult CmpHelperNSEQ(const char* expected_expression,
+                                         const char* actual_expression,
+                                         id<NSObject> expected,
+                                         id<NSObject> actual) {
+  if ([expected isEqual:actual]) {
+    return AssertionSuccess();
+  }
+  return EqFailure(expected_expression,
+                   actual_expression,
+                   String([[expected description] UTF8String]),
+                   String([[actual description] UTF8String]),
+                   false);
+}
+
+// This overloaded version allows comparison between ObjC objects that conform
+// to the NSObject protocol. Used to implement {ASSERT|EXPECT}_NE().
+GTEST_API_ AssertionResult CmpHelperNSNE(const char* expected_expression,
+                                         const char* actual_expression,
+                                         id<NSObject> expected,
+                                         id<NSObject> actual) {
+  if (![expected isEqual:actual]) {
+    return AssertionSuccess();
+  }
+  Message msg;
+  msg << "Expected: (" << expected_expression << ") != (" << actual_expression
+      << "), actual: " << String([[expected description] UTF8String])
+      << " vs " << String([[actual description] UTF8String]);
+  return AssertionFailure(msg);
+}
+
+}  // namespace internal
+}  // namespace testing
+
+#endif  // GTEST_OS_MAC