Added test files for SystemInfo.m and OmahaXMLRequest.m.

chrome/installer/mac/app/testing/OmahaXMLRequest_test.mm

Index: chrome/installer/mac/app/testing/OmahaXMLRequest_test.mm
diff --git a/chrome/installer/mac/app/testing/OmahaXMLRequest_test.mm b/chrome/installer/mac/app/testing/OmahaXMLRequest_test.mm
new file mode 100644
index 0000000000000000000000000000000000000000..e6ea398e4a24d4f455a620a2e518f6501ce022e5
--- /dev/null
+++ b/chrome/installer/mac/app/testing/OmahaXMLRequest_test.mm
@@ -0,0 +1,37 @@
+// Copyright 2016 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.
+
+#include "base/mac/scoped_nsobject.h"
+#include "base/macros.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+#import "chrome/installer/mac/app/OmahaXMLRequest.h"
+
+namespace {
+
+class OmahaXMLRequestTest : public ::testing::Test {
+ protected:
+  OmahaXMLRequestTest() : xml_body_([OmahaXMLRequest createXMLRequestBody]) {}
+
+  base::scoped_nsobject<NSXMLDocument> xml_body_;
+};
+
+TEST_F(OmahaXMLRequestTest, CreateDoesNotReturnNil) {
+  EXPECT_TRUE(xml_body_);

[Mark Mentovai, 2016/07/22 15:42:38]

(this is what I was talking about—this was unaddressed from the last round of
feedback.)

[Anna Zeng, 2016/07/22 16:58:02]

Done.

+}
+
+TEST_F(OmahaXMLRequestTest, CreateReturnsValidXML) {
+  NSString* requestDTDLocation =

[Mark Mentovai, 2016/07/22 15:42:38]

When you move EXPECT_TRUE(xml_body_) here, you’ll notice that you have this one
test class that does one thing ([OmahaXMLRequest createXMLRequestBody]) for one
caller only (OmahaXMLRequestTest.CreateReturnsValidXML). Seems kinda spread out
and not all that necessary!

At that point, you don’t need the test class at all! You can just write this as
a TEST() (not TEST_F()) that starts out as:

  base::scoped_nsobject<NSXMLDocument> xml_body(
      [OmahaXMLRequest createXMLRequestBody]);
  ASSERT_TRUE(xml_body);

  NSString* requestDTDLocation = …

Note the use of ASSERT_TRUE instead of EXPECT_TRUE now. That’s because if
xml_body is nil, it’s pointless to continue the test. ASSERT_TRUE will stop it
dead in its tracks right there. If we allowed it to continue, surely we’d hit
another error at the EXPECT_TRUE at the bottom of the function, because sending
a message to the nil xml_body would return nil, which would fail the
EXPECT_TRUE. But that second failure would just mask the first, real one, which
is that xml_body was nil to begin with.

[Anna Zeng, 2016/07/22 16:58:02]

Thanks Mark! This is a good point here -- if the assertion fails I'll be able to
correctly figure out that xml_body was nil.

+      [[[NSFileManager defaultManager] currentDirectoryPath]
+          stringByAppendingString:@"/testing/requestCheck.dtd"];
+  NSData* requestDTDData = [NSData dataWithContentsOfFile:requestDTDLocation];
+  NSError* error;
+  NSXMLDTD* requestXMLChecker =
+      [[NSXMLDTD alloc] initWithData:requestDTDData options:0 error:&error];
+  [requestXMLChecker setName:@"request"];
+  [xml_body_ setDTD:requestXMLChecker];
+  EXPECT_TRUE([xml_body_ validateAndReturnError:&error]);
+}
+
+}  // namespace