Fix coloring madness in depot_tools.

git_common.py

 # Copyright 2014 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.
 
 # Monkeypatch IMapIterator so that Ctrl-C can kill everything properly.
 # Derived from https://gist.github.com/aljungberg/626518
 import multiprocessing.pool
 from multiprocessing.pool import IMapIterator
 def wrapper(func):
   def wrap(self, timeout=None):
     return func(self, timeout=timeout or 1e100)
   return wrap
 IMapIterator.next = wrapper(IMapIterator.next)
 IMapIterator.__next__ = IMapIterator.next
 # TODO(iannucci): Monkeypatch all other 'wait' methods too.
 
 
 import binascii
 import collections
 import contextlib
 import functools
 import logging
 import os
 import re
+import setup_color
 import shutil
 import signal
 import sys
 import tempfile
 import textwrap
 import threading
 
 import subprocess2
 
 ROOT = os.path.abspath(os.path.dirname(__file__))
@@ skipping 239 matching lines @@
   def _inner_gen():
     yield function()
     while True:
       yield
   return _inner_gen().next
 
 
 ## Git functions
 
 
-def blame(filename, revision=None, porcelain=False, *args):
+def blame(filename, revision=None, porcelain=False, *_args):
   command = ['blame']
   if porcelain:
     command.append('-p')
   if revision is not None:
     command.append(revision)
   command.extend(['--', filename])
   return run(*command)
 
 
 def branch_config(branch, option, default=None):
@@ skipping 274 matching lines @@
   return config('depot-tools.upstream', 'origin/master')
 
 
 @contextlib.contextmanager
 def less():  # pragma: no cover
   """Runs 'less' as context manager yielding its stdin as a PIPE.
 
   Automatically checks if sys.stdout is a non-TTY stream. If so, it avoids
   running less and just yields sys.stdout.
   """
-  if not sys.stdout.isatty():
+  if not setup_color.IS_TTY:
     yield sys.stdout
     return
 
   # Run with the same options that git uses (see setup_pager in git repo).
   # -F: Automatically quit if the output is less than one screen.
   # -R: Don't escape ANSI color codes.
   # -X: Don't clear the screen before starting.
   cmd = ('less', '-FRX')
   try:
     proc = subprocess2.Popen(cmd, stdin=subprocess2.PIPE)
@@ skipping 313 matching lines @@
                       ['HEAD'])
 
 
 def clone_file(repository, new_workdir, link, operation):
   if not os.path.exists(os.path.join(repository, link)):
     return
   link_dir = os.path.dirname(os.path.join(new_workdir, link))
   if not os.path.exists(link_dir):
     os.makedirs(link_dir)
   operation(os.path.join(repository, link), os.path.join(new_workdir, link))