Parallelize pylint PRESUBMIT checks.

tests/presubmit_unittest.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.
 
 """Unit tests for presubmit_support.py and presubmit_canned_checks.py."""
 
 # pylint: disable=E1101,E1103
 
 import functools
@@ skipping 1165 matching lines @@
     except SystemExit, e:
       self.assertEquals(2, e.code)
 
 
 class InputApiUnittest(PresubmitTestsBase):
   """Tests presubmit.InputApi."""
   def testMembersChanged(self):
     self.mox.ReplayAll()
     members = [
       'AbsoluteLocalPaths', 'AffectedFiles', 'AffectedSourceFiles',
-      'AffectedTextFiles',
-      'DEFAULT_BLACK_LIST', 'DEFAULT_WHITE_LIST',
-      'DepotToLocalPath', 'FilterSourceFile', 'LocalPaths',
-      'LocalToDepotPath', 'Command', 'RunTests',
-      'PresubmitLocalPath', 'ReadFile', 'RightHandSideLines', 'ServerPaths',
-      'basename', 'cPickle', 'cpplint', 'cStringIO', 'canned_checks', 'change',
-      'environ', 'glob', 'host_url', 'is_committing', 'json', 'logging',
-      'marshal', 'os_listdir', 'os_walk', 'os_path', 'os_stat', 'owners_db',
-      'pickle', 'platform', 'python_executable', 're', 'rietveld', 'subprocess',
-      'tbr', 'tempfile', 'time', 'traceback', 'unittest', 'urllib2', 'version',
-      'verbose',
+      'AffectedTextFiles', 'DEFAULT_BLACK_LIST', 'DEFAULT_WHITE_LIST',
+      'DepotToLocalPath', 'FilterSourceFile', 'LocalPaths', 'LocalToDepotPath',
+      'Command', 'RunTests', 'PresubmitLocalPath', 'ReadFile',
+      'RightHandSideLines', 'ServerPaths', 'basename', 'cPickle', 'cpplint',
+      'cStringIO', 'canned_checks', 'change', 'cpu_count', 'environ', 'glob',
+      'host_url', 'is_committing', 'json', 'logging', 'marshal', 'os_listdir',
+      'os_walk', 'os_path', 'os_stat', 'owners_db', 'pickle', 'platform',
+      'python_executable', 're', 'rietveld', 'subprocess', 'tbr', 'tempfile',
+      'time', 'traceback', 'unittest', 'urllib2', 'version', 'verbose',
     ]
     # If this test fails, you should add the relevant test.
     self.compareMembers(
         presubmit.InputApi(self.fake_change, './.', False, None, False),
         members)
 
   def testDepotToLocalPath(self):
     presubmit.scm.SVN._CaptureInfo(['svn://foo/smurf'], self.fake_root_dir
         ).AndReturn({'Path': 'prout'})
     presubmit.scm.SVN._CaptureInfo(
@@ skipping 638 matching lines @@
         return 'foo'
     input_api.subprocess.CalledProcessError = fake_CalledProcessError
     input_api.verbose = False
 
     input_api.change = change
     input_api.host_url = 'http://localhost'
     input_api.is_committing = committing
     input_api.tbr = False
     input_api.python_executable = 'pyyyyython'
     input_api.platform = sys.platform
+    input_api.cpu_count = 2
     input_api.time = time
     input_api.canned_checks = presubmit_canned_checks
     input_api.Command = presubmit.CommandData
     input_api.RunTests = functools.partial(
         presubmit.InputApi.RunTests, input_api)
     return input_api
 
   def testMembersChanged(self):
     self.mox.ReplayAll()
     members = [
@@ skipping 1025 matching lines @@
         owners_check=False)
     self.assertEqual(1, len(results))
     self.assertEqual(
         'Found line ending with white spaces in:', results[0]._message)
     self.checkstdout('')
 
 
 if __name__ == '__main__':
   import unittest
   unittest.main()