diff --git a/git_drover.py b/git_drover.py
index 24eb077a89..12021bf241 100755
--- a/git_drover.py
+++ b/git_drover.py
@@ -7,7 +7,6 @@
 from __future__ import print_function
 
 import argparse
-import cPickle
 import functools
 import logging
 import os
@@ -19,6 +18,10 @@ import tempfile
 
 import git_common
 
+if sys.version_info.major == 2:
+  import cPickle
+else:
+  import pickle as cPickle
 
 class Error(Exception):
   pass
@@ -67,6 +70,12 @@ else:
   mk_symlink = os.symlink
 
 
+def _raw_input(message):
+  # Use this so that it can be mocked in tests on Python 2 and 3.
+  if sys.version_info.major == 2:
+    return raw_input(message)
+  return input(message)
+
 class _Drover(object):
 
   def __init__(self, branch, revision, parent_repo, dry_run, verbose):
@@ -183,7 +192,7 @@ class _Drover(object):
     result = ''
     while result not in ('y', 'n'):
       try:
-        result = raw_input('%s Continue (y/n)? ' % message)
+        result = _raw_input('%s Continue (y/n)? ' % message)
       except EOFError:
         result = 'n'
     return result == 'y'
@@ -268,9 +277,9 @@ class _Drover(object):
         ['-c', 'core.quotePath=false', 'status', '--porcelain']).splitlines()
     extra_files = [f[3:] for f in repo_status if f[:2] == ' D']
     if extra_files:
+      stdin = '\n'.join(extra_files) + '\n'
       self._run_git_command_with_stdin(
-          ['update-index', '--skip-worktree', '--stdin'],
-          stdin='\n'.join(extra_files) + '\n')
+          ['update-index', '--skip-worktree', '--stdin'], stdin=stdin.encode())
 
   def _upload_and_land(self):
     if self._dry_run:
diff --git a/tests/git_drover_test.py b/tests/git_drover_test.py
index c5e49441fa..f7a7fc3f78 100755
--- a/tests/git_drover_test.py
+++ b/tests/git_drover_test.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env vpython3
 # Copyright 2015 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.
@@ -13,14 +13,15 @@ import unittest
 
 sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 
-from testing_support import auto_stub
+from third_party import mock
 import git_drover
 
 
-class GitDroverTest(auto_stub.TestCase):
+class GitDroverTest(unittest.TestCase):
 
   def setUp(self):
     super(GitDroverTest, self).setUp()
+    self.maxDiff = None
     self._temp_directory = tempfile.mkdtemp()
     self._parent_repo = os.path.join(self._temp_directory, 'parent_repo')
     self._target_repo = os.path.join(self._temp_directory, 'drover_branch_123')
@@ -33,12 +34,14 @@ class GitDroverTest(auto_stub.TestCase):
     with open(
         os.path.join(self._parent_repo, '.git', 'info', 'refs'), 'w') as f:
       f.write('refs')
-    self.mock(tempfile, 'mkdtemp', self._mkdtemp)
-    self.mock(__builtins__, 'raw_input', self._get_input)
-    self.mock(subprocess, 'check_call', self._check_call)
-    self.mock(subprocess, 'check_output', self._check_call)
+    mock.patch('tempfile.mkdtemp', self._mkdtemp).start()
+    mock.patch('git_drover._raw_input', self._get_input).start()
+    mock.patch('subprocess.check_call', self._check_call).start()
+    mock.patch('subprocess.check_output', self._check_call).start()
     self.real_popen = subprocess.Popen
-    self.mock(subprocess, 'Popen', self._Popen)
+    mock.patch('subprocess.Popen', self._Popen).start()
+    self.addCleanup(mock.patch.stopall)
+
     self._commands = []
     self._input = []
     self._fail_on_command = None
@@ -131,7 +134,7 @@ class GitDroverTest(auto_stub.TestCase):
         def __init__(self, *args, **kwargs):
           self.returncode = -999
         def communicate(self, stdin):
-          if stdin == 'foo\nbar\n':
+          if stdin == b'foo\nbar\n':
             self.returncode = 0
           else:
             self.returncode = 1