Add infra_libs as a bootstrap dependency.

infra_libs/time_functions/testing.py

-# 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.
-
-
-"""Provides functions to mock current time in tests."""
-
-import datetime
-import functools
-import mock
-import pytz
-import tzlocal
-
-
-def mock_datetime_utc(*dec_args, **dec_kwargs):
-  """Overrides built-in datetime and date classes to always return a given time.
-
-  Args:
-    Same arguments as datetime.datetime accepts to mock UTC time.
-  
-  Example usage:
-    @mock_datetime_utc(2015, 10, 11, 20, 0, 0)
-    def my_test(self):
-      hour_ago_utc = datetime.datetime.utcnow() - datetime.timedelta(hours=1)
-      self.assertEqual(hour_ago_utc, datetime.datetime(2015, 10, 11, 19, 0, 0))
-
-  Note that if you are using now() and today() methods, you should also use
-  mock_timezone decorator to have consistent test results across timezones:
-
-    @mock_timezone('US/Pacific')
-    @mock_datetime_utc(2015, 10, 11, 20, 0, 0)
-    def my_test(self):
-      local_dt = datetime.datetime.now()
-      self.assertEqual(local_dt, datetime.datetime(2015, 10, 11, 12, 0, 0))
-  """
-  # We record original values currently stored in the datetime.datetime and
-  # datetime.date here. Note that they are no necessarily vanilla Python types
-  # and can already be mock classes - this can happen if nested mocking is used.
-  original_datetime = datetime.datetime
-  original_date = datetime.date
-
-  # Our metaclass must be derived from the parent class metaclass, but if the
-  # parent class doesn't have one, we use 'type' type.
-  class MockDateTimeMeta(original_datetime.__dict__.get('__metaclass__', type)):
-    @classmethod
-    def __instancecheck__(cls, instance):
-      return isinstance(instance, original_datetime)
-
-  class _MockDateTime(original_datetime):
-    __metaclass__ = MockDateTimeMeta
-    mock_utcnow = original_datetime(*dec_args, **dec_kwargs)
-  
-    @classmethod
-    def utcnow(cls):
-      return cls.mock_utcnow
-  
-    @classmethod
-    def now(cls, tz=None):
-      if not tz:
-        tz = tzlocal.get_localzone()
-      tzaware_utcnow = pytz.utc.localize(cls.mock_utcnow)
-      return tz.normalize(tzaware_utcnow.astimezone(tz)).replace(tzinfo=None)
-  
-    @classmethod
-    def today(cls):
-      return cls.now().date()
-
-    @classmethod
-    def fromtimestamp(cls, timestamp, tz=None):
-      if not tz:
-        # TODO(sergiyb): This may fail for some unclear reason because pytz
-        # doesn't find normal timezones such as 'Europe/Berlin'. This seems to
-        # happen only in appengine/chromium_try_flakes tests, and not in tests
-        # for this module itself.
-        tz = tzlocal.get_localzone()
-      tzaware_dt = pytz.utc.localize(cls.utcfromtimestamp(timestamp))
-      return tz.normalize(tzaware_dt.astimezone(tz)).replace(tzinfo=None)
-  
-  # Our metaclass must be derived from the parent class metaclass, but if the
-  # parent class doesn't have one, we use 'type' type.
-  class MockDateMeta(original_date.__dict__.get('__metaclass__', type)):
-    @classmethod
-    def __instancecheck__(cls, instance):
-      return isinstance(instance, original_date)
-
-  class _MockDate(original_date):
-    __metaclass__ = MockDateMeta
-
-    @classmethod
-    def today(cls):
-      return _MockDateTime.today()
-
-    @classmethod
-    def fromtimestamp(cls, timestamp, tz=None):
-      return _MockDateTime.fromtimestamp(timestamp, tz).date()
-
-  def decorator(func):
-    @functools.wraps(func)
-    def wrapper(*args, **kwargs):
-      with mock.patch('datetime.datetime', _MockDateTime):
-        with mock.patch('datetime.date', _MockDate):
-          return func(*args, **kwargs)
-    return wrapper
-  return decorator
-
-
-def mock_timezone(tzname):
-  """Mocks tzlocal.get_localzone method to always return a given timezone.
-
-  This should be used in combination with mock_datetime_utc in order to achieve
-  consistent test results accross timezones if datetime.now, datetime.today or
-  date.today functions are used.
-  
-  Args:
-    tzname: Name of the timezone to be used (as passed to pytz.timezone).
-  """
-  # TODO(sergiyb): Also mock other common libraries, e.g. time, pytz.reference.
-  def decorator(func):
-    @functools.wraps(func)
-    def wrapper(*args, **kwargs):
-      with mock.patch('tzlocal.get_localzone', lambda: pytz.timezone(tzname)):
-        return func(*args, **kwargs)
-    return wrapper
-  return decorator