cit: print to stderr to allow piping from cit log cat.

cit.py

 #!/usr/bin/env python
 # Copyright (c) 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.
 
 
 """Wrapper for updating and calling infra.git tools.
 
 This tool does a two things:
 * Maintains a infra.git checkout pinned at "deployed" in the home dir
@@ skipping 38 matching lines @@
 
   subprocess.check_call(
       ['git', 'fetch', 'origin'], cwd=INFRA_DIR,
       stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
   origin_rev = get_git_rev(INFRA_DIR, 'origin/%s' % (branch,))
   return origin_rev != local_rev
 
 
 def ensure_infra(branch):
   """Ensures that infra.git is present in ~/.chrome-infra."""
-  print 'Fetching infra@%s into %s, may take a couple of minutes...' % (
-      branch, TARGET_DIR)
+  sys.stderr.write(

[Ryan Tseng, 2016/06/14 17:41:08]

use print >>sys.stderr, "..."

Either that, or add a newline.  I like using print >> pipe better.

[tandrii(chromium), 2016/06/14 18:09:40]

Actually, the whole reason for using stderr.write is so that I avoid new line. I
wanted to see one line like this:

checking out infra..... done.

+      'Fetching infra@%s into %s, may take a couple of minutes...' % (
+      branch, TARGET_DIR))
+  sys.stderr.flush()
   if not os.path.isdir(TARGET_DIR):
     os.mkdir(TARGET_DIR)
   if not os.path.exists(os.path.join(TARGET_DIR, '.gclient')):
     subprocess.check_call(
         [sys.executable, os.path.join(SCRIPT_DIR, 'fetch.py'), 'infra'],
         cwd=TARGET_DIR,
         stdout=subprocess.PIPE)
   subprocess.check_call(
       [sys.executable, GCLIENT, 'sync', '--revision', 'origin/%s' % (branch,)],
       cwd=TARGET_DIR,
       stdout=subprocess.PIPE)
+  sys.stderr.write(' done.\n')
+  sys.stderr.flush()
 
 
 def get_available_tools():
   tools = []
   starting = os.path.join(TARGET_DIR, 'infra', 'infra', 'tools')
   for root, _, files in os.walk(starting):
     if '__main__.py' in files:
       tools.append(root[len(starting)+1:].replace(os.path.sep, '.'))
   return sorted(tools)
 
@@ skipping 29 matching lines @@
     args.args.pop(0)
   if extras:
     args.args = extras + args.args
 
   if need_to_update(args.infra_branch):
     ensure_infra(args.infra_branch)
   return run(args.args)
 
 if __name__ == '__main__':
   sys.exit(main())