tests/gclient_scm_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.

"""Unit tests for gclient_scm.py."""

# pylint: disable=E1103

# Import before super_mox to keep valid references.
from shutil import rmtree
from subprocess import Popen, PIPE, STDOUT

import json
import logging
import os
import re
import sys
import tempfile
import unittest

sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))

from testing_support import fake_repos
from testing_support.super_mox import mox, StdoutCheck, SuperMoxTestBase
from testing_support.super_mox import TestCaseUtils

import gclient_scm
import git_cache
import subprocess2

# Disable global git cache
git_cache.Mirror.SetCachePath(None)

# Shortcut since this function is used often
join = gclient_scm.os.path.join

TIMESTAMP_RE = re.compile('\[[0-9]{1,2}:[0-9]{2}:[0-9]{2}\] (.*)', re.DOTALL)
def strip_timestamps(value):
  lines = value.splitlines(True)
  for i in xrange(len(lines)):
    m = TIMESTAMP_RE.match(lines[i])
    if m:
      lines[i] = m.group(1)
  return ''.join(lines)


class GCBaseTestCase(object):
  def assertRaisesError(self, msg, fn, *args, **kwargs):
    """Like unittest's assertRaises() but checks for Gclient.Error."""
    try:
      fn(*args, **kwargs)
    except gclient_scm.gclient_utils.Error, e:
      self.assertEquals(e.args[0], msg)
    else:
      self.fail('%s not raised' % msg)


class BaseTestCase(GCBaseTestCase, SuperMoxTestBase):
  def setUp(self):
    SuperMoxTestBase.setUp(self)
    self.mox.StubOutWithMock(gclient_scm.gclient_utils, 'CheckCallAndFilter')
    self.mox.StubOutWithMock(gclient_scm.gclient_utils,
        'CheckCallAndFilterAndHeader')
    self.mox.StubOutWithMock(gclient_scm.gclient_utils, 'FileRead')
    self.mox.StubOutWithMock(gclient_scm.gclient_utils, 'FileWrite')
    self.mox.StubOutWithMock(gclient_scm.gclient_utils, 'rmtree')
    self.mox.StubOutWithMock(subprocess2, 'communicate')
    self.mox.StubOutWithMock(subprocess2, 'Popen')
    self._scm_wrapper = gclient_scm.GitWrapper
    self._original_GitBinaryExists = gclient_scm.GitWrapper.BinaryExists
    gclient_scm.GitWrapper.BinaryExists = staticmethod(lambda : True)
    # Absolute path of the fake checkout directory.
    self.base_path = join(self.root_dir, self.relpath)

  def tearDown(self):
    SuperMoxTestBase.tearDown(self)
    gclient_scm.GitWrapper.BinaryExists = self._original_GitBinaryExists


class BasicTests(SuperMoxTestBase):
  def setUp(self):
    SuperMoxTestBase.setUp(self)

  def testGetFirstRemoteUrl(self):
    REMOTE_STRINGS = [('remote.origin.url E:\\foo\\bar', 'E:\\foo\\bar'),
                      ('remote.origin.url /b/foo/bar', '/b/foo/bar'),
                      ('remote.origin.url https://foo/bar', 'https://foo/bar'),
                      ('remote.origin.url E:\\Fo Bar\\bax', 'E:\\Fo Bar\\bax'),
                      ('remote.origin.url git://what/"do', 'git://what/"do')]
    FAKE_PATH = '/fake/path'
    self.mox.StubOutWithMock(gclient_scm.scm.GIT, 'Capture')
    for question, _ in REMOTE_STRINGS:
      gclient_scm.scm.GIT.Capture(
          ['config', '--local', '--get-regexp', r'remote.*.url'],
          cwd=FAKE_PATH).AndReturn(question)

    self.mox.ReplayAll()

    for _, answer in REMOTE_STRINGS:
      self.assertEquals(gclient_scm.SCMWrapper._get_first_remote_url(FAKE_PATH),
                        answer)

  def tearDown(self):
    SuperMoxTestBase.tearDown(self)


class BaseGitWrapperTestCase(GCBaseTestCase, StdoutCheck, TestCaseUtils,
                             unittest.TestCase):
  """This class doesn't use pymox."""
  class OptionsObject(object):
    def __init__(self, verbose=False, revision=None):
      self.auto_rebase = False
      self.verbose = verbose
      self.revision = revision
      self.deps_os = None
      self.force = False
      self.reset = False
      self.nohooks = False
      self.no_history = False
      self.upstream = False
      self.cache_dir = None
      self.merge = False
      self.jobs = 1
      self.break_repo_locks = False
      self.delete_unversioned_trees = False
      self.patch_ref = None
      self.patch_repo = None
      self.rebase_patch_ref = True
      self.reset_patch_ref = True

  sample_git_import = """blob
mark :1
data 6
Hello

blob
mark :2
data 4
Bye

reset refs/heads/master
commit refs/heads/master
mark :3
author Bob <bob@example.com> 1253744361 -0700
committer Bob <bob@example.com> 1253744361 -0700
data 8
A and B
M 100644 :1 a
M 100644 :2 b

blob
mark :4
data 10
Hello
You

blob
mark :5
data 8
Bye
You

commit refs/heads/origin
mark :6
author Alice <alice@example.com> 1253744424 -0700
committer Alice <alice@example.com> 1253744424 -0700
data 13
Personalized
from :3
M 100644 :4 a
M 100644 :5 b

blob
mark :7
data 5
Mooh

commit refs/heads/feature
mark :8
author Bob <bob@example.com> 1390311986 -0000
committer Bob <bob@example.com> 1390311986 -0000
data 6
Add C
from :3
M 100644 :7 c

reset refs/heads/master
from :3
"""
  def Options(self, *args, **kwargs):
    return self.OptionsObject(*args, **kwargs)

  def checkstdout(self, expected):
    value = sys.stdout.getvalue()
    sys.stdout.close()
    # pylint: disable=no-member
    self.assertEquals(expected, strip_timestamps(value))

  @staticmethod
  def CreateGitRepo(git_import, path):
    """Do it for real."""
    try:
      Popen(['git', 'init', '-q'], stdout=PIPE, stderr=STDOUT,
            cwd=path).communicate()
    except OSError:
      # git is not available, skip this test.
      return False
    Popen(['git', 'fast-import', '--quiet'], stdin=PIPE, stdout=PIPE,
        stderr=STDOUT, cwd=path).communicate(input=git_import)
    Popen(['git', 'checkout', '-q'], stdout=PIPE, stderr=STDOUT,
        cwd=path).communicate()
    Popen(['git', 'remote', 'add', '-f', 'origin', '.'], stdout=PIPE,
        stderr=STDOUT, cwd=path).communicate()
    Popen(['git', 'checkout', '-b', 'new', 'origin/master', '-q'], stdout=PIPE,
        stderr=STDOUT, cwd=path).communicate()
    Popen(['git', 'push', 'origin', 'origin/origin:origin/master', '-q'],
        stdout=PIPE, stderr=STDOUT, cwd=path).communicate()
    Popen(['git', 'config', '--unset', 'remote.origin.fetch'], stdout=PIPE,
        stderr=STDOUT, cwd=path).communicate()
    Popen(['git', 'config', 'user.email', 'someuser@chromium.org'], stdout=PIPE,
        stderr=STDOUT, cwd=path).communicate()
    Popen(['git', 'config', 'user.name', 'Some User'], stdout=PIPE,
        stderr=STDOUT, cwd=path).communicate()
    return True

  def _GetAskForDataCallback(self, expected_prompt, return_value):
    def AskForData(prompt, options):
      self.assertEquals(prompt, expected_prompt)
      return return_value
    return AskForData

  def setUp(self):
    TestCaseUtils.setUp(self)
    unittest.TestCase.setUp(self)
    self.url = 'git://foo'
    # The .git suffix allows gclient_scm to recognize the dir as a git repo
    # when cloning it locally
    self.root_dir = tempfile.mkdtemp('.git')
    self.relpath = '.'
    self.base_path = join(self.root_dir, self.relpath)
    self.enabled = self.CreateGitRepo(self.sample_git_import, self.base_path)
    StdoutCheck.setUp(self)
    self._original_GitBinaryExists = gclient_scm.GitWrapper.BinaryExists
    gclient_scm.GitWrapper.BinaryExists = staticmethod(lambda : True)

  def tearDown(self):
    try:
      rmtree(self.root_dir)
      StdoutCheck.tearDown(self)
      TestCaseUtils.tearDown(self)
      unittest.TestCase.tearDown(self)
    finally:
      # TODO(maruel): Use auto_stub.TestCase.
      gclient_scm.GitWrapper.BinaryExists = self._original_GitBinaryExists


class ManagedGitWrapperTestCase(BaseGitWrapperTestCase):

  def testRevertMissing(self):
    if not self.enabled:
      return
    options = self.Options()
    file_path = join(self.base_path, 'a')
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    scm.update(options, None, file_list)
    gclient_scm.os.remove(file_path)
    file_list = []
    scm.revert(options, self.args, file_list)
    self.assertEquals(file_list, [file_path])
    file_list = []
    scm.diff(options, self.args, file_list)
    self.assertEquals(file_list, [])
    sys.stdout.close()

  def testRevertNone(self):
    if not self.enabled:
      return
    options = self.Options()
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    scm.update(options, None, file_list)
    file_list = []
    scm.revert(options, self.args, file_list)
    self.assertEquals(file_list, [])
    self.assertEquals(scm.revinfo(options, self.args, None),
                      'a7142dc9f0009350b96a11f372b6ea658592aa95')
    sys.stdout.close()

  def testRevertModified(self):
    if not self.enabled:
      return
    options = self.Options()
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    scm.update(options, None, file_list)
    file_path = join(self.base_path, 'a')
    open(file_path, 'a').writelines('touched\n')
    file_list = []
    scm.revert(options, self.args, file_list)
    self.assertEquals(file_list, [file_path])
    file_list = []
    scm.diff(options, self.args, file_list)
    self.assertEquals(file_list, [])
    self.assertEquals(scm.revinfo(options, self.args, None),
                      'a7142dc9f0009350b96a11f372b6ea658592aa95')
    sys.stdout.close()

  def testRevertNew(self):
    if not self.enabled:
      return
    options = self.Options()
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    scm.update(options, None, file_list)
    file_path = join(self.base_path, 'c')
    f = open(file_path, 'w')
    f.writelines('new\n')
    f.close()
    Popen(['git', 'add', 'c'], stdout=PIPE,
          stderr=STDOUT, cwd=self.base_path).communicate()
    file_list = []
    scm.revert(options, self.args, file_list)
    self.assertEquals(file_list, [file_path])
    file_list = []
    scm.diff(options, self.args, file_list)
    self.assertEquals(file_list, [])
    self.assertEquals(scm.revinfo(options, self.args, None),
                      'a7142dc9f0009350b96a11f372b6ea658592aa95')
    sys.stdout.close()

  def testStatusNew(self):
    if not self.enabled:
      return
    options = self.Options()
    file_path = join(self.base_path, 'a')
    open(file_path, 'a').writelines('touched\n')
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    scm.status(options, self.args, file_list)
    self.assertEquals(file_list, [file_path])
    self.checkstdout(
        ('\n________ running \'git -c core.quotePath=false diff --name-status '
         '069c602044c5388d2d15c3f875b057c852003458\' in \'%s\'\nM\ta\n') %
            join(self.root_dir, '.'))

  def testStatus2New(self):
    if not self.enabled:
      return
    options = self.Options()
    expected_file_list = []
    for f in ['a', 'b']:
      file_path = join(self.base_path, f)
      open(file_path, 'a').writelines('touched\n')
      expected_file_list.extend([file_path])
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    scm.status(options, self.args, file_list)
    expected_file_list = [join(self.base_path, x) for x in ['a', 'b']]
    self.assertEquals(sorted(file_list), expected_file_list)
    self.checkstdout(
        ('\n________ running \'git -c core.quotePath=false diff --name-status '
         '069c602044c5388d2d15c3f875b057c852003458\' in \'%s\'\nM\ta\nM\tb\n') %
            join(self.root_dir, '.'))

  def testUpdateUpdate(self):
    if not self.enabled:
      return
    options = self.Options()
    expected_file_list = [join(self.base_path, x) for x in ['a', 'b']]
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    scm.update(options, (), file_list)
    self.assertEquals(file_list, expected_file_list)
    self.assertEquals(scm.revinfo(options, (), None),
                      'a7142dc9f0009350b96a11f372b6ea658592aa95')
    sys.stdout.close()

  def testUpdateMerge(self):
    if not self.enabled:
      return
    options = self.Options()
    options.merge = True
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    scm._Run(['checkout', '-q', 'feature'], options)
    rev = scm.revinfo(options, (), None)
    file_list = []
    scm.update(options, (), file_list)
    self.assertEquals(file_list, [join(self.base_path, x)
                                  for x in ['a', 'b', 'c']])
    # The actual commit that is created is unstable, so we verify its tree and
    # parents instead.
    self.assertEquals(scm._Capture(['rev-parse', 'HEAD:']),
                      'd2e35c10ac24d6c621e14a1fcadceb533155627d')
    self.assertEquals(scm._Capture(['rev-parse', 'HEAD^1']), rev)
    self.assertEquals(scm._Capture(['rev-parse', 'HEAD^2']),
                      scm._Capture(['rev-parse', 'origin/master']))
    sys.stdout.close()

  def testUpdateRebase(self):
    if not self.enabled:
      return
    options = self.Options()
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    scm._Run(['checkout', '-q', 'feature'], options)
    file_list = []
    # Fake a 'y' key press.
    scm._AskForData = self._GetAskForDataCallback(
        'Cannot fast-forward merge, attempt to rebase? '
        '(y)es / (q)uit / (s)kip : ', 'y')
    scm.update(options, (), file_list)
    self.assertEquals(file_list, [join(self.base_path, x)
                                  for x in ['a', 'b', 'c']])
    # The actual commit that is created is unstable, so we verify its tree and
    # parent instead.
    self.assertEquals(scm._Capture(['rev-parse', 'HEAD:']),
                      'd2e35c10ac24d6c621e14a1fcadceb533155627d')
    self.assertEquals(scm._Capture(['rev-parse', 'HEAD^']),
                      scm._Capture(['rev-parse', 'origin/master']))
    sys.stdout.close()

  def testUpdateReset(self):
    if not self.enabled:
      return
    options = self.Options()
    options.reset = True

    dir_path = join(self.base_path, 'c')
    os.mkdir(dir_path)
    open(join(dir_path, 'nested'), 'w').writelines('new\n')

    file_path = join(self.base_path, 'file')
    open(file_path, 'w').writelines('new\n')

    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    scm.update(options, (), file_list)
    self.assert_(gclient_scm.os.path.isdir(dir_path))
    self.assert_(gclient_scm.os.path.isfile(file_path))
    sys.stdout.close()

  def testUpdateResetUnsetsFetchConfig(self):
    if not self.enabled:
      return
    options = self.Options()
    options.reset = True

    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    scm._Run(['config', 'remote.origin.fetch',
              '+refs/heads/bad/ref:refs/remotes/origin/bad/ref'], options)

    file_list = []
    scm.update(options, (), file_list)
    self.assertEquals(scm.revinfo(options, (), None),
                      '069c602044c5388d2d15c3f875b057c852003458')
    sys.stdout.close()

  def testUpdateResetDeleteUnversionedTrees(self):
    if not self.enabled:
      return
    options = self.Options()
    options.reset = True
    options.delete_unversioned_trees = True

    dir_path = join(self.base_path, 'dir')
    os.mkdir(dir_path)
    open(join(dir_path, 'nested'), 'w').writelines('new\n')

    file_path = join(self.base_path, 'file')
    open(file_path, 'w').writelines('new\n')

    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    scm.update(options, (), file_list)
    self.assert_(not gclient_scm.os.path.isdir(dir_path))
    self.assert_(gclient_scm.os.path.isfile(file_path))
    sys.stdout.close()

  def testUpdateUnstagedConflict(self):
    if not self.enabled:
      return
    options = self.Options()
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_path = join(self.base_path, 'b')
    open(file_path, 'w').writelines('conflict\n')
    try:
      scm.update(options, (), [])
      self.fail()
    except (gclient_scm.gclient_utils.Error, subprocess2.CalledProcessError):
      # The exact exception text varies across git versions so it's not worth
      # verifying it. It's fine as long as it throws.
      pass
    # Manually flush stdout since we can't verify it's content accurately across
    # git versions.
    sys.stdout.getvalue()
    sys.stdout.close()

  @unittest.skip('Skipping until crbug.com/670884 is resolved.')
  def testUpdateLocked(self):
    if not self.enabled:
      return
    options = self.Options()
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_path = join(self.base_path, '.git', 'index.lock')
    with open(file_path, 'w'):
      pass
    with self.assertRaises(subprocess2.CalledProcessError):
      scm.update(options, (), [])
    sys.stdout.close()

  def testUpdateLockedBreak(self):
    if not self.enabled:
      return
    options = self.Options()
    options.break_repo_locks = True
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_path = join(self.base_path, '.git', 'index.lock')
    with open(file_path, 'w'):
      pass
    scm.update(options, (), [])
    self.assertRegexpMatches(sys.stdout.getvalue(),
                             "breaking lock.*\.git/index\.lock")
    self.assertFalse(os.path.exists(file_path))
    sys.stdout.close()

  def testUpdateConflict(self):
    if not self.enabled:
      return
    options = self.Options()
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_path = join(self.base_path, 'b')
    open(file_path, 'w').writelines('conflict\n')
    scm._Run(['commit', '-am', 'test'], options)
    scm._AskForData = self._GetAskForDataCallback(
        'Cannot fast-forward merge, attempt to rebase? '
        '(y)es / (q)uit / (s)kip : ', 'y')
    exception = ('Conflict while rebasing this branch.\n'
                 'Fix the conflict and run gclient again.\n'
                 'See \'man git-rebase\' for details.\n')
    self.assertRaisesError(exception, scm.update, options, (), [])
    exception = ('\n____ . at refs/remotes/origin/master\n'
                 '\tYou have unstaged changes.\n'
                 '\tPlease commit, stash, or reset.\n')
    self.assertRaisesError(exception, scm.update, options, (), [])
    sys.stdout.close()

  def testRevinfo(self):
    if not self.enabled:
      return
    options = self.Options()
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    rev_info = scm.revinfo(options, (), None)
    self.assertEquals(rev_info, '069c602044c5388d2d15c3f875b057c852003458')

  def testMirrorPushUrl(self):
    if not self.enabled:
      return
    fakes = fake_repos.FakeRepos()
    fakes.set_up_git()
    self.url = fakes.git_base + 'repo_1'
    self.root_dir = fakes.root_dir
    self.addCleanup(fake_repos.FakeRepos.tear_down_git, fakes)

    mirror = tempfile.mkdtemp()
    self.addCleanup(rmtree, mirror)

    # This should never happen, but if it does, it'd render the other assertions
    # in this test meaningless.
    self.assertFalse(self.url.startswith(mirror))

    git_cache.Mirror.SetCachePath(mirror)
    self.addCleanup(git_cache.Mirror.SetCachePath, None)

    options = self.Options()
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, self.relpath)
    self.assertIsNotNone(scm._GetMirror(self.url, options))
    scm.update(options, (), [])

    fetch_url = scm._Capture(['remote', 'get-url', 'origin'])
    self.assertTrue(
        fetch_url.startswith(mirror),
        msg='\n'.join([
            'Repository fetch url should be in the git cache mirror directory.',
            '  fetch_url: %s' % fetch_url,
            '  mirror:    %s' % mirror]))
    push_url = scm._Capture(['remote', 'get-url', '--push', 'origin'])
    self.assertEquals(push_url, self.url)
    sys.stdout.close()


class ManagedGitWrapperTestCaseMox(BaseTestCase):
  class OptionsObject(object):
    def __init__(self, verbose=False, revision=None, force=False):
      self.verbose = verbose
      self.revision = revision
      self.deps_os = None
      self.force = force
      self.reset = False
      self.nohooks = False
      self.break_repo_locks = False
      # TODO(maruel): Test --jobs > 1.
      self.jobs = 1
      self.patch_ref = None
      self.patch_repo = None
      self.rebase_patch_ref = True

  def Options(self, *args, **kwargs):
    return self.OptionsObject(*args, **kwargs)

  def checkstdout(self, expected):
    value = sys.stdout.getvalue()
    sys.stdout.close()
    # pylint: disable=no-member
    self.assertEquals(expected, strip_timestamps(value))

  def setUp(self):
    BaseTestCase.setUp(self)
    self.fake_hash_1 = 't0ta11yf4k3'
    self.fake_hash_2 = '3v3nf4k3r'
    self.url = 'git://foo'
    self.root_dir = '/tmp' if sys.platform != 'win32' else 't:\\tmp'
    self.relpath = 'fake'
    self.base_path = os.path.join(self.root_dir, self.relpath)
    self.backup_base_path = os.path.join(self.root_dir,
                                         'old_%s.git' % self.relpath)

  def tearDown(self):
    BaseTestCase.tearDown(self)

  def testGetUsableRevGit(self):
    # pylint: disable=no-member
    options = self.Options(verbose=True)

    self.mox.StubOutWithMock(gclient_scm.scm.GIT, 'IsValidRevision', True)
    gclient_scm.scm.GIT.IsValidRevision(cwd=self.base_path, rev=self.fake_hash_1
        ).AndReturn(True)
    gclient_scm.scm.GIT.IsValidRevision(cwd=self.base_path, rev='1'
        ).AndReturn(False)
    gclient_scm.scm.GIT.IsValidRevision(cwd=self.base_path, rev='1'
        ).AndReturn(False)

    self.mox.StubOutWithMock(gclient_scm.GitWrapper, '_Fetch', True)
    # pylint: disable=no-value-for-parameter
    gclient_scm.GitWrapper._Fetch(options).AndReturn(None)

    gclient_scm.scm.os.path.isdir(self.base_path).AndReturn(True)
    gclient_scm.os.path.isdir(self.base_path).AndReturn(True)

    self.mox.ReplayAll()

    git_scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                     self.relpath)
    # A [fake] git sha1 with a git repo should work (this is in the case that
    # the LKGR gets flipped to git sha1's some day).
    self.assertEquals(git_scm.GetUsableRev(self.fake_hash_1, options),
                      self.fake_hash_1)
    # An SVN rev with an existing purely git repo should raise an exception.
    self.assertRaises(gclient_scm.gclient_utils.Error,
                      git_scm.GetUsableRev, '1', options)

  def testUpdateNoDotGit(self):
    options = self.Options()

    gclient_scm.os.path.isdir(
        os.path.join(self.base_path, '.git', 'hooks')).AndReturn(False)
    gclient_scm.os.path.exists(self.backup_base_path).AndReturn(False)
    gclient_scm.os.path.exists(self.base_path).AndReturn(True)
    gclient_scm.os.path.isdir(self.base_path).AndReturn(True)
    gclient_scm.os.path.exists(os.path.join(self.base_path, '.git')
                               ).AndReturn(False)
    self.mox.StubOutWithMock(gclient_scm.GitWrapper, '_Clone', True)
    # pylint: disable=no-value-for-parameter
    gclient_scm.GitWrapper._Clone('refs/remotes/origin/master', self.url,
                                  options)
    self.mox.StubOutWithMock(gclient_scm.subprocess2, 'check_output', True)
    gclient_scm.subprocess2.check_output(
        ['git', '-c', 'core.quotePath=false', 'ls-files'], cwd=self.base_path,
        env=gclient_scm.scm.GIT.ApplyEnvVars({}), stderr=-1,).AndReturn('')
    gclient_scm.subprocess2.check_output(
        ['git', 'rev-parse', '--verify', 'HEAD'],
        cwd=self.base_path,
        env=gclient_scm.scm.GIT.ApplyEnvVars({}),
        stderr=-1,
        ).AndReturn('')

    self.mox.ReplayAll()
    scm = self._scm_wrapper(self.url, self.root_dir,
                            self.relpath)
    scm.update(options, None, [])
    self.checkstdout('\n')

  def testUpdateConflict(self):
    options = self.Options()

    gclient_scm.os.path.isdir(
        os.path.join(self.base_path, '.git', 'hooks')).AndReturn(False)
    gclient_scm.os.path.exists(self.backup_base_path).AndReturn(False)
    gclient_scm.os.path.exists(self.base_path).AndReturn(True)
    gclient_scm.os.path.isdir(self.base_path).AndReturn(True)
    gclient_scm.os.path.exists(os.path.join(self.base_path, '.git')
                               ).AndReturn(False)
    self.mox.StubOutWithMock(gclient_scm.GitWrapper, '_Clone', True)
    # pylint: disable=no-value-for-parameter
    gclient_scm.GitWrapper._Clone(
        'refs/remotes/origin/master', self.url, options
    ).AndRaise(gclient_scm.subprocess2.CalledProcessError(None, None, None,
                                                          None, None))
    self.mox.StubOutWithMock(gclient_scm.GitWrapper, '_DeleteOrMove', True)
    gclient_scm.GitWrapper._DeleteOrMove(False)
    gclient_scm.GitWrapper._Clone('refs/remotes/origin/master', self.url,
                                  options)
    self.mox.StubOutWithMock(gclient_scm.subprocess2, 'check_output', True)
    gclient_scm.subprocess2.check_output(
        ['git', '-c', 'core.quotePath=false', 'ls-files'], cwd=self.base_path,
        env=gclient_scm.scm.GIT.ApplyEnvVars({}), stderr=-1,).AndReturn('')
    gclient_scm.subprocess2.check_output(
        ['git', 'rev-parse', '--verify', 'HEAD'],
        cwd=self.base_path,
        env=gclient_scm.scm.GIT.ApplyEnvVars({}),
        stderr=-1,
        ).AndReturn('')

    self.mox.ReplayAll()
    scm = self._scm_wrapper(self.url, self.root_dir,
                            self.relpath)
    scm.update(options, None, [])
    self.checkstdout('\n')


class UnmanagedGitWrapperTestCase(BaseGitWrapperTestCase):
  def checkInStdout(self, expected):
    value = sys.stdout.getvalue()
    sys.stdout.close()
    # pylint: disable=no-member
    self.assertIn(expected, value)

  def checkNotInStdout(self, expected):
    value = sys.stdout.getvalue()
    sys.stdout.close()
    # pylint: disable=no-member
    self.assertNotIn(expected, value)

  def getCurrentBranch(self):
    # Returns name of current branch or HEAD for detached HEAD
    branch = gclient_scm.scm.GIT.Capture(['rev-parse', '--abbrev-ref', 'HEAD'],
                                          cwd=self.base_path)
    if branch == 'HEAD':
      return None
    return branch

  def testUpdateClone(self):
    if not self.enabled:
      return
    options = self.Options()

    origin_root_dir = self.root_dir
    self.root_dir = tempfile.mkdtemp()
    self.relpath = '.'
    self.base_path = join(self.root_dir, self.relpath)

    scm = gclient_scm.GitWrapper(origin_root_dir,
                                 self.root_dir,
                                 self.relpath)

    expected_file_list = [join(self.base_path, "a"),
                          join(self.base_path, "b")]
    file_list = []
    options.revision = 'unmanaged'
    scm.update(options, (), file_list)

    self.assertEquals(file_list, expected_file_list)
    self.assertEquals(scm.revinfo(options, (), None),
                      '069c602044c5388d2d15c3f875b057c852003458')
    # indicates detached HEAD
    self.assertEquals(self.getCurrentBranch(), None)
    self.checkInStdout(
      'Checked out refs/remotes/origin/master to a detached HEAD')

    rmtree(origin_root_dir)

  def testUpdateCloneOnCommit(self):
    if not self.enabled:
      return
    options = self.Options()

    origin_root_dir = self.root_dir
    self.root_dir = tempfile.mkdtemp()
    self.relpath = '.'
    self.base_path = join(self.root_dir, self.relpath)
    url_with_commit_ref = origin_root_dir +\
                          '@a7142dc9f0009350b96a11f372b6ea658592aa95'

    scm = gclient_scm.GitWrapper(url_with_commit_ref,
                                 self.root_dir,
                                 self.relpath)

    expected_file_list = [join(self.base_path, "a"),
                          join(self.base_path, "b")]
    file_list = []
    options.revision = 'unmanaged'
    scm.update(options, (), file_list)

    self.assertEquals(file_list, expected_file_list)
    self.assertEquals(scm.revinfo(options, (), None),
                      'a7142dc9f0009350b96a11f372b6ea658592aa95')
    # indicates detached HEAD
    self.assertEquals(self.getCurrentBranch(), None)
    self.checkInStdout(
      'Checked out a7142dc9f0009350b96a11f372b6ea658592aa95 to a detached HEAD')

    rmtree(origin_root_dir)

  def testUpdateCloneOnBranch(self):
    if not self.enabled:
      return
    options = self.Options()

    origin_root_dir = self.root_dir
    self.root_dir = tempfile.mkdtemp()
    self.relpath = '.'
    self.base_path = join(self.root_dir, self.relpath)
    url_with_branch_ref = origin_root_dir + '@feature'

    scm = gclient_scm.GitWrapper(url_with_branch_ref,
                                 self.root_dir,
                                 self.relpath)

    expected_file_list = [join(self.base_path, "a"),
                          join(self.base_path, "b"),
                          join(self.base_path, "c")]
    file_list = []
    options.revision = 'unmanaged'
    scm.update(options, (), file_list)

    self.assertEquals(file_list, expected_file_list)
    self.assertEquals(scm.revinfo(options, (), None),
                      '9a51244740b25fa2ded5252ca00a3178d3f665a9')
    # indicates detached HEAD
    self.assertEquals(self.getCurrentBranch(), None)
    self.checkInStdout(
        'Checked out 9a51244740b25fa2ded5252ca00a3178d3f665a9 '
        'to a detached HEAD')

    rmtree(origin_root_dir)

  def testUpdateCloneOnFetchedRemoteBranch(self):
    if not self.enabled:
      return
    options = self.Options()

    origin_root_dir = self.root_dir
    self.root_dir = tempfile.mkdtemp()
    self.relpath = '.'
    self.base_path = join(self.root_dir, self.relpath)
    url_with_branch_ref = origin_root_dir + '@refs/remotes/origin/feature'

    scm = gclient_scm.GitWrapper(url_with_branch_ref,
                                 self.root_dir,
                                 self.relpath)

    expected_file_list = [join(self.base_path, "a"),
                          join(self.base_path, "b"),
                          join(self.base_path, "c")]
    file_list = []
    options.revision = 'unmanaged'
    scm.update(options, (), file_list)

    self.assertEquals(file_list, expected_file_list)
    self.assertEquals(scm.revinfo(options, (), None),
                      '9a51244740b25fa2ded5252ca00a3178d3f665a9')
    # indicates detached HEAD
    self.assertEquals(self.getCurrentBranch(), None)
    self.checkInStdout(
      'Checked out refs/remotes/origin/feature to a detached HEAD')

    rmtree(origin_root_dir)

  def testUpdateCloneOnTrueRemoteBranch(self):
    if not self.enabled:
      return
    options = self.Options()

    origin_root_dir = self.root_dir
    self.root_dir = tempfile.mkdtemp()
    self.relpath = '.'
    self.base_path = join(self.root_dir, self.relpath)
    url_with_branch_ref = origin_root_dir + '@refs/heads/feature'

    scm = gclient_scm.GitWrapper(url_with_branch_ref,
                                 self.root_dir,
                                 self.relpath)

    expected_file_list = [join(self.base_path, "a"),
                          join(self.base_path, "b"),
                          join(self.base_path, "c")]
    file_list = []
    options.revision = 'unmanaged'
    scm.update(options, (), file_list)

    self.assertEquals(file_list, expected_file_list)
    self.assertEquals(scm.revinfo(options, (), None),
                      '9a51244740b25fa2ded5252ca00a3178d3f665a9')
    # @refs/heads/feature is AKA @refs/remotes/origin/feature in the clone, so
    # should be treated as such by gclient.
    # TODO(mmoss): Though really, we should only allow DEPS to specify branches
    # as they are known in the upstream repo, since the mapping into the local
    # repo can be modified by users (or we might even want to change the gclient
    # defaults at some point). But that will take more work to stop using
    # refs/remotes/ everywhere that we do (and to stop assuming a DEPS ref will
    # always resolve locally, like when passing them to show-ref or rev-list).
    self.assertEquals(self.getCurrentBranch(), None)
    self.checkInStdout(
      'Checked out refs/remotes/origin/feature to a detached HEAD')

    rmtree(origin_root_dir)

  def testUpdateUpdate(self):
    if not self.enabled:
      return
    options = self.Options()
    expected_file_list = []
    scm = gclient_scm.GitWrapper(self.url, self.root_dir,
                                 self.relpath)
    file_list = []
    options.revision = 'unmanaged'
    scm.update(options, (), file_list)
    self.assertEquals(file_list, expected_file_list)
    self.assertEquals(scm.revinfo(options, (), None),
                      '069c602044c5388d2d15c3f875b057c852003458')
    self.checkstdout('________ unmanaged solution; skipping .\n')


class CipdWrapperTestCase(BaseTestCase):

  def setUp(self):
    # Create this before setting up mocks.
    self._cipd_root_dir = tempfile.mkdtemp()
    self._workdir = tempfile.mkdtemp()
    BaseTestCase.setUp(self)

    self._cipd_instance_url = 'https://chrome-infra-packages.appspot.com'
    self._cipd_root = gclient_scm.CipdRoot(
        self._cipd_root_dir,
        self._cipd_instance_url)
    self._cipd_packages = [
        self._cipd_root.add_package('f', 'foo_package', 'foo_version'),
        self._cipd_root.add_package('b', 'bar_package', 'bar_version'),
        self._cipd_root.add_package('b', 'baz_package', 'baz_version'),
    ]
    self.mox.StubOutWithMock(self._cipd_root, 'add_package')
    self.mox.StubOutWithMock(self._cipd_root, 'clobber')
    self.mox.StubOutWithMock(self._cipd_root, 'ensure')

  def tearDown(self):
    BaseTestCase.tearDown(self)
    rmtree(self._cipd_root_dir)
    rmtree(self._workdir)

  def createScmWithPackageThatSatisfies(self, condition):
    return gclient_scm.CipdWrapper(
        url=self._cipd_instance_url,
        root_dir=self._cipd_root_dir,
        relpath='fake_relpath',
        root=self._cipd_root,
        package=self.getPackageThatSatisfies(condition))

  def getPackageThatSatisfies(self, condition):
    for p in self._cipd_packages:
      if condition(p):
        return p

    self.fail('Unable to find a satisfactory package.')

  def testRevert(self):
    """Checks that revert does nothing."""
    scm = self.createScmWithPackageThatSatisfies(
        lambda _: True)

    self.mox.ReplayAll()

    scm.revert(None, (), [])

  def testRevinfo(self):
    """Checks that revinfo uses the JSON from cipd describe."""
    scm = self.createScmWithPackageThatSatisfies(lambda _: True)

    expected_revinfo = '0123456789abcdef0123456789abcdef01234567'
    json_contents = {
        'result': {
            'pin': {
                'instance_id': expected_revinfo,
            }
        }
    }
    describe_json_path = join(self._workdir, 'describe.json')
    with open(describe_json_path, 'w') as describe_json:
      json.dump(json_contents, describe_json)

    cmd = [
        'cipd', 'describe', 'foo_package',
        '-log-level', 'error',
        '-version', 'foo_version',
        '-json-output', describe_json_path,
    ]

    self.mox.StubOutWithMock(tempfile, 'mkdtemp')

    tempfile.mkdtemp().AndReturn(self._workdir)
    gclient_scm.gclient_utils.CheckCallAndFilter(
        cmd, filter_fn=mox.IgnoreArg(), print_stdout=False)
    gclient_scm.gclient_utils.rmtree(self._workdir)

    self.mox.ReplayAll()

    revinfo = scm.revinfo(None, (), [])
    self.assertEquals(revinfo, expected_revinfo)

  def testUpdate(self):
    """Checks that update does nothing."""
    scm = self.createScmWithPackageThatSatisfies(
        lambda _: True)

    self.mox.ReplayAll()

    scm.update(None, (), [])


class GerritChangesFakeRepo(fake_repos.FakeReposBase):
  def populateGit(self):
    # Creates a tree that looks like this:
    #
    #       6 refs/changes/35/1235/1
    #       |
    #       5 refs/changes/34/1234/1
    #       |
    # 1--2--3--4 refs/heads/master
    #    |  |
    #    |  11(5)--12 refs/heads/master-with-5
    #    |
    #    7--8--9 refs/heads/feature
    #       |
    #       10 refs/changes/36/1236/1
    #

    self._commit_git('repo_1', {'commit 1': 'touched'})
    self._commit_git('repo_1', {'commit 2': 'touched'})
    self._commit_git('repo_1', {'commit 3': 'touched'})
    self._commit_git('repo_1', {'commit 4': 'touched'})
    self._create_ref('repo_1', 'refs/heads/master', 4)

    # Create a change on top of commit 3 that consists of two commits.
    self._commit_git('repo_1',
                     {'commit 5': 'touched',
                      'change': '1234'},
                     base=3)
    self._create_ref('repo_1', 'refs/changes/34/1234/1', 5)
    self._commit_git('repo_1',
                     {'commit 6': 'touched',
                      'change': '1235'})
    self._create_ref('repo_1', 'refs/changes/35/1235/1', 6)

    # Create a refs/heads/feature branch on top of commit 2, consisting of three
    # commits.
    self._commit_git('repo_1', {'commit 7': 'touched'}, base=2)
    self._commit_git('repo_1', {'commit 8': 'touched'})
    self._commit_git('repo_1', {'commit 9': 'touched'})
    self._create_ref('repo_1', 'refs/heads/feature', 9)

    # Create a change of top of commit 8.
    self._commit_git('repo_1',
                     {'commit 10': 'touched',
                      'change': '1236'},
                     base=8)
    self._create_ref('repo_1', 'refs/changes/36/1236/1', 10)

    # Create a refs/heads/master-with-5 on top of commit 3 which is a branch
    # where refs/changes/34/1234/1 (commit 5) has already landed as commit 11.
    self._commit_git('repo_1',
                     # This is really commit 11, but has the changes of commit 5
                     {'commit 5': 'touched',
                      'change': '1234'},
                     base=3)
    self._commit_git('repo_1', {'commit 12': 'touched'})
    self._create_ref('repo_1', 'refs/heads/master-with-5', 12)


class GerritChangesTest(fake_repos.FakeReposTestBase):
  FAKE_REPOS_CLASS = GerritChangesFakeRepo

  def setUp(self):
    super(GerritChangesTest, self).setUp()
    self.enabled = self.FAKE_REPOS.set_up_git()
    self.options = BaseGitWrapperTestCase.OptionsObject()
    self.url = self.git_base + 'repo_1'
    self.mirror = None

  def setUpMirror(self):
    self.mirror = tempfile.mkdtemp()
    git_cache.Mirror.SetCachePath(self.mirror)
    self.addCleanup(rmtree, self.mirror)
    self.addCleanup(git_cache.Mirror.SetCachePath, None)

  def assertCommits(self, commits):
    """Check that all, and only |commits| are present in the current checkout.
    """
    for i in commits:
      name = os.path.join(self.root_dir, 'commit ' + str(i))
      self.assertTrue(os.path.exists(name), 'Commit not found: %s' % name)

    all_commits = set(range(1, len(self.FAKE_REPOS.git_hashes['repo_1'])))
    for i in all_commits - set(commits):
      name = os.path.join(self.root_dir, 'commit ' + str(i))
      self.assertFalse(os.path.exists(name), 'Unexpected commit: %s' % name)

  def testCanCloneGerritChange(self):
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    self.options.revision = 'refs/changes/35/1235/1'
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 6), self.gitrevparse(self.root_dir))

  def testCanSyncToGerritChange(self):
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    self.options.revision = self.githash('repo_1', 1)
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 1), self.gitrevparse(self.root_dir))

    self.options.revision = 'refs/changes/35/1235/1'
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 6), self.gitrevparse(self.root_dir))

  def testCanCloneGerritChangeMirror(self):
    self.setUpMirror()
    self.testCanCloneGerritChange()

  def testCanSyncToGerritChangeMirror(self):
    self.setUpMirror()
    self.testCanSyncToGerritChange()

  def testAppliesPatchOnTopOfMasterByDefault(self):
    """Test the default case, where we apply a patch on top of master."""
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    # Make sure we don't specify a revision.
    self.options.revision = None
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 4), self.gitrevparse(self.root_dir))

    scm.apply_patch_ref(self.url, 'refs/changes/35/1235/1', None, self.options,
                        file_list)

    self.assertCommits([1, 2, 3, 4, 5, 6])
    self.assertEqual(self.githash('repo_1', 4), self.gitrevparse(self.root_dir))

  def testCheckoutOlderThanPatchBase(self):
    """Test applying a patch on an old checkout.

    We first checkout commit 1, and try to patch refs/changes/35/1235/1, which
    contains commits 5 and 6, and is based on top of commit 3.
    The final result should contain commits 1, 5 and 6, but not commits 2 or 3.
    """
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    # Sync to commit 1
    self.options.revision = self.githash('repo_1', 1)
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 1), self.gitrevparse(self.root_dir))

    # Apply the change on top of that.
    scm.apply_patch_ref(self.url, 'refs/changes/35/1235/1', None, self.options,
                        file_list)

    self.assertCommits([1, 5, 6])
    self.assertEqual(self.githash('repo_1', 1), self.gitrevparse(self.root_dir))

  def testCheckoutOriginFeature(self):
    """Tests that we can apply a patch on a branch other than master."""
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    # Sync to origin/feature
    self.options.revision = 'origin/feature'
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 9), self.gitrevparse(self.root_dir))

    # Apply the change on top of that.
    scm.apply_patch_ref(self.url, 'refs/changes/36/1236/1', None, self.options,
                        file_list)

    self.assertCommits([1, 2, 7, 8, 9, 10])
    self.assertEqual(self.githash('repo_1', 9), self.gitrevparse(self.root_dir))

  def testCheckoutOriginFeatureOnOldRevision(self):
    """Tests that we can apply a patch on an old checkout, on a branch other
    than master."""
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    # Sync to origin/feature on an old revision
    self.options.revision = self.githash('repo_1', 7)
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 7), self.gitrevparse(self.root_dir))

    # Apply the change on top of that.
    scm.apply_patch_ref(self.url, 'refs/changes/36/1236/1', None, self.options,
                        file_list)

    # We shouldn't have rebased on top of 2 (which is the merge base between
    # origin/master and the change) but on top of 7 (which is the merge base
    # between origin/feature and the change).
    self.assertCommits([1, 2, 7, 10])
    self.assertEqual(self.githash('repo_1', 7), self.gitrevparse(self.root_dir))

  def testCheckoutOriginFeaturePatchBranch(self):
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    # Sync to the hash instead of 'origin/feature'
    self.options.revision = self.githash('repo_1', 9)
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 9), self.gitrevparse(self.root_dir))

    # Apply refs/changes/34/1234/1, created for branch 'origin/master' on top of
    # 'origin/feature'.
    scm.apply_patch_ref(self.url, 'refs/changes/35/1235/1', 'origin/master',
                        self.options, file_list)

    # Commits 5 and 6 are part of the patch, and commits 1, 2, 7, 8 and 9 are
    # part of 'origin/feature'.
    self.assertCommits([1, 2, 5, 6, 7, 8, 9])
    self.assertEqual(self.githash('repo_1', 9), self.gitrevparse(self.root_dir))

  def testDoesntRebasePatchMaster(self):
    """Tests that we can apply a patch without rebasing it.
    """
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    self.options.rebase_patch_ref = False
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 4), self.gitrevparse(self.root_dir))

    # Apply the change on top of that.
    scm.apply_patch_ref(self.url, 'refs/changes/35/1235/1', None, self.options,
                        file_list)

    self.assertCommits([1, 2, 3, 5, 6])
    self.assertEqual(self.githash('repo_1', 4), self.gitrevparse(self.root_dir))

  def testDoesntRebasePatchOldCheckout(self):
    """Tests that we can apply a patch without rebasing it on an old checkout.
    """
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    # Sync to commit 1
    self.options.revision = self.githash('repo_1', 1)
    self.options.rebase_patch_ref = False
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 1), self.gitrevparse(self.root_dir))

    # Apply the change on top of that.
    scm.apply_patch_ref(self.url, 'refs/changes/35/1235/1', None, self.options,
                        file_list)

    self.assertCommits([1, 2, 3, 5, 6])
    self.assertEqual(self.githash('repo_1', 1), self.gitrevparse(self.root_dir))

  def testDoesntSoftResetIfNotAskedTo(self):
    """Test that we can apply a patch without doing a soft reset."""
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    self.options.reset_patch_ref = False
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 4), self.gitrevparse(self.root_dir))

    scm.apply_patch_ref(self.url, 'refs/changes/35/1235/1', None, self.options,
                        file_list)

    self.assertCommits([1, 2, 3, 4, 5, 6])
    # The commit hash after cherry-picking is not known, but it must be
    # different from what the repo was synced at before patching.
    self.assertNotEqual(self.githash('repo_1', 4),
                        self.gitrevparse(self.root_dir))

  def testRecoversAfterPatchFailure(self):
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    self.options.revision = 'refs/changes/34/1234/1'
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 5), self.gitrevparse(self.root_dir))

    # Checkout 'refs/changes/34/1234/1' modifies the 'change' file, so trying to
    # patch 'refs/changes/36/1236/1' creates a patch failure.
    with self.assertRaises(subprocess2.CalledProcessError) as cm:
      scm.apply_patch_ref(self.url, 'refs/changes/36/1236/1', None,
                          self.options, file_list)
    self.assertEqual(cm.exception.cmd[:2], ['git', 'cherry-pick'])
    self.assertIn('error: could not apply', cm.exception.stderr)

    # Try to apply 'refs/changes/35/1235/1', which doesn't have a merge
    # conflict.
    scm.apply_patch_ref(self.url, 'refs/changes/35/1235/1', None, self.options,
                        file_list)
    self.assertCommits([1, 2, 3, 5, 6])
    self.assertEqual(self.githash('repo_1', 5), self.gitrevparse(self.root_dir))

  def testIgnoresAlreadyMergedCommits(self):
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    self.options.revision = 'refs/heads/master-with-5'
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 12),
                     self.gitrevparse(self.root_dir))

    # When we try 'refs/changes/35/1235/1' on top of 'refs/heads/feature',
    # 'refs/changes/34/1234/1' will be an empty commit, since the changes were
    # already present in the tree as commit 11.
    # Make sure we deal with this gracefully.
    scm.apply_patch_ref(self.url, 'refs/changes/35/1235/1', None, self.options,
                        file_list)
    self.assertCommits([1, 2, 3, 5, 6, 12])
    self.assertEqual(self.githash('repo_1', 12),
                     self.gitrevparse(self.root_dir))

  def testRecoversFromExistingCherryPick(self):
    scm = gclient_scm.GitWrapper(self.url, self.root_dir, '.')
    file_list = []

    self.options.revision = 'refs/changes/34/1234/1'
    scm.update(self.options, None, file_list)
    self.assertEqual(self.githash('repo_1', 5), self.gitrevparse(self.root_dir))

    # Checkout 'refs/changes/34/1234/1' modifies the 'change' file, so trying to
    # cherry-pick 'refs/changes/36/1236/1' raises an error.
    scm._Run(['fetch', 'origin', 'refs/changes/36/1236/1'], self.options)
    with self.assertRaises(subprocess2.CalledProcessError) as cm:
      scm._Run(['cherry-pick', 'FETCH_HEAD'], self.options)
    self.assertEqual(cm.exception.cmd[:2], ['git', 'cherry-pick'])

    # Try to apply 'refs/changes/35/1235/1', which doesn't have a merge
    # conflict.
    scm.apply_patch_ref(self.url, 'refs/changes/35/1235/1', None, self.options,
                        file_list)
    self.assertCommits([1, 2, 3, 5, 6])
    self.assertEqual(self.githash('repo_1', 5), self.gitrevparse(self.root_dir))


if __name__ == '__main__':
  level = logging.DEBUG if '-v' in sys.argv else logging.FATAL
  logging.basicConfig(
      level=level,
      format='%(asctime).19s %(levelname)s %(filename)s:'
             '%(lineno)s %(message)s')
  unittest.main()

# vim: ts=2:sw=2:tw=80:et: