Adding _Check* function for invalid OS_MACROs in src/PRESUBMIT.py

PRESUBMIT_test.py

 #!/usr/bin/env python
 # Copyright (c) 2012 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 os
 import re
 import unittest
 
 import PRESUBMIT
@@ skipping 277 matching lines @@
 
     contents = ['#include "ipc/some_macros.h"',
                 '#include "b.h"'
                 '#include "a.h"']
     mock_file = MockFile('', contents)
     warnings = PRESUBMIT._CheckIncludeOrderInFile(
         mock_input_api, mock_file, range(1, len(contents) + 1))
     self.assertEqual(0, len(warnings))
 
 
-class VersionControlerConflictsTest(unittest.TestCase):
+class VersionControlConflictsTest(unittest.TestCase):
   def testTypicalConflict(self):
     lines = ['<<<<<<< HEAD',
              '  base::ScopedTempDir temp_dir_;',
              '=======',
              '  ScopedTempDir temp_dir_;',
              '>>>>>>> master']
     errors = PRESUBMIT._CheckForVersionControlConflictsInFile(
         MockInputApi(), MockFile('some/path/foo_platform.cc', lines))
     self.assertEqual(3, len(errors))
     self.assertTrue('1' in errors[0])
@@ skipping 40 matching lines @@
 
   def testOnlyOwnersFiles(self):
     mock_change = MockChange([
       'some/path/OWNERS',
       'A\Windows\Path\OWNERS',
     ])
     results = PRESUBMIT.GetPreferredTrySlaves(None, mock_change)
     self.assertEqual(0, len(results))
 
 
+class InvalidOSMacroNamesTest(unittest.TestCase):
+  def testInvalidOSMacroNames(self):
+    lines = ['#if defined(OS_WINDOWS)',
+             ' #elif defined(OS_WINDOW)',
+             ' # if defined(OS_MACOSX) || defined(OS_CHROME)',
+             '# else  // defined(OS_MAC)',
+             '#endif  // defined(OS_MACOS)']
+    errors = PRESUBMIT._CheckForInvalidOSMacrosInFile(
+        MockInputApi(), MockFile('some/path/foo_platform.cc', lines))
+    self.assertEqual(len(lines), len(errors))
+    self.assertTrue(errors[0].endswith(':1 OS_WINDOWS'))
+
+  def testValidOSMacroNames(self):
+    lines = ['#if defined(%s)' % m for m in PRESUBMIT._VALID_OS_MACROS]
+    errors = PRESUBMIT._CheckForInvalidOSMacrosInFile(
+        MockInputApi(), MockFile('some/path/foo_platform.cc', lines))
+    self.assertEqual(0, len(errors))
+
+
 if __name__ == '__main__':
   unittest.main()