chrome/common/extensions/docs/server2/test_util.py

   1 # Copyright 2013 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 from __future__ import print_function
   6
   7 import logging
   8 import os
   9 import sys
  10
  11
  12 def CaptureLogging(f):
  13   '''Call the function |f|, capturing any logging output generated. |f| must
  14   take no arguments. Returns a list of LogRecords that were emitted.
  15   '''
  16   output = []
  17   class Capture(object):
  18     def filter(self, record):
  19       output.append(record)
  20
  21   cf = Capture()
  22   logging.getLogger('').addFilter(cf)
  23   f()
  24   logging.getLogger('').removeFilter(cf)
  25
  26   return output
  27
  28
  29 def EnableLogging(name):
  30   '''Returns the output of the log with |name| to stdout.
  31   '''
  32
  33   return _ReplaceLogging(name, lambda message, *args: print(message % args))
  34
  35
  36 def DisableLogging(name):
  37   '''Disables the log with |name| for the duration of the decorated function.
  38   '''
  39   return _ReplaceLogging(name, lambda _, *args: None)
  40
  41
  42 def _ReplaceLogging(name, replacement):
  43   def decorator(fn):
  44     def impl(*args, **optargs):
  45       saved = getattr(logging, name)
  46       setattr(logging, name, replacement)
  47       try:
  48         return fn(*args, **optargs)
  49       finally:
  50         setattr(logging, name, saved)
  51     return impl
  52   return decorator
  53
  54
  55 def ChromiumPath(*path):
  56   return os.path.join(
  57       sys.path[0], '..', '..', '..', '..', '..', *path)
  58
  59
  60 def ReadFile(*path, **read_args):
  61   with open(ChromiumPath(*path), **read_args) as f:
  62     return f.read()