Add --commit option and some polish to update_node.py.

tools/release/test_update_node.py

 #!/usr/bin/env python
 # Copyright 2017 the V8 project 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 shutil
 import subprocess
 import sys
 import tempfile
@@ skipping 11 matching lines @@
 !/testing/gtest/include
 /testing/gtest/include/*
 !/testing/gtest/include/gtest
 /testing/gtest/include/gtest/*
 !/testing/gtest/include/gtest/gtest_prod.h
 !/third_party/jinja2
 !/third_party/markupsafe
 /unrelated
 """
 
+EXPECTED_GIT_DIFF = """
+ rename deps/v8/baz/{delete_me => v8_new} (100%)
+ rename deps/v8/{delete_me => new/v8_new} (100%)
+ create mode 100644 deps/v8/third_party/jinja2/jinja2
+ create mode 100644 deps/v8/third_party/markupsafe/markupsafe
+ create mode 100644 deps/v8/v8_new
+"""
+
 ADDED_FILES = [
   'v8_new',
   'new/v8_new',
   'baz/v8_new',
   'testing/gtest/gtest_new',
   'testing/gtest/new/gtest_new',
   'testing/gtest/baz/gtest_new',
   'third_party/jinja2/jinja2',
   'third_party/markupsafe/markupsafe'
 ]
 
 REMOVED_FILES = [
   'delete_me',
   'baz/delete_me',
   'testing/gtest/delete_me',
   'testing/gtest/baz/delete_me',
 ]
 
 def gitify(path):
   files = os.listdir(path)
   subprocess.check_call(['git', 'init'], cwd=path)
   subprocess.check_call(['git', 'add'] + files, cwd=path)
-  subprocess.check_call(['git', 'commit', '-m="Initial"'], cwd=path)
+  subprocess.check_call(['git', 'commit', '-m', 'Initial'], cwd=path)
 
 
 class TestUpdateNode(unittest.TestCase):
   def setUp(self):
     self.workdir = tempfile.mkdtemp(prefix='tmp_test_node_')
 
   def tearDown(self):
     shutil.rmtree(self.workdir)
 
   def testUpdate(self):
     v8_cwd = os.path.join(self.workdir, 'v8')
     node_cwd = os.path.join(self.workdir, 'node')
 
     # Set up V8 test fixture.
     shutil.copytree(src=os.path.join(TEST_DATA, 'v8'), dst=v8_cwd)
     gitify(v8_cwd)
     for repository in update_node.SUB_REPOSITORIES:
       gitify(os.path.join(v8_cwd, *repository))
 
-    # Set up node test fixture (no git repo required).
+    # Set up node test fixture.
     shutil.copytree(src=os.path.join(TEST_DATA, 'node'), dst=node_cwd)
+    gitify(os.path.join(node_cwd))
 
     # Run update script.
-    update_node.Main([v8_cwd, node_cwd])
+    update_node.Main([v8_cwd, node_cwd, "--commit"])
 
     # Check expectations.
     with open(os.path.join(node_cwd, 'deps', 'v8', '.gitignore')) as f:
       actual_gitignore = f.read()
     self.assertEquals(EXPECTED_GITIGNORE.strip(), actual_gitignore.strip())
     for f in ADDED_FILES:
       added_file = os.path.join(node_cwd, 'deps', 'v8', *f.split('/'))
       self.assertTrue(os.path.exists(added_file))
     for f in REMOVED_FILES:
       removed_file = os.path.join(node_cwd, 'deps', 'v8', *f.split('/'))
       self.assertFalse(os.path.exists(removed_file))
+    gitlog = subprocess.check_output(['git', 'diff', 'master', '--summary'],
+                                     cwd=node_cwd)
+    self.assertEquals(EXPECTED_GIT_DIFF.strip(), gitlog.strip())
 
 if __name__ == "__main__":
   unittest.main()