libfaketime 0.0.2

A fast alternative to freezegun that wraps libfaketime.

python-libfaketime is a wrapper of libfaketime for python.

import datetime

from libfaketime import fake_time, reexec_if_needed

# libfaketime needs to be preloaded by the dynamic linker.
# This will exec the same command, but with the proper environment variables set.
# Or you can skip running this and manually manage your env (see get_reload_information()).
reexec_if_needed()

def get_tomorrow():
    return datetime.date.today() + datetime.timedelta(days=1)


@fake_time('2014-01-01 00:00:00')
def test_get_tomorrow():
    assert get_tomorrow() == datetime.date(2014, 1, 2)

It serves as a fast drop-in replacement for freezegun. Here’s the output of a totally unscientific benchmark on my laptop:

$ python benchmark.py
re-exec with libfaketime dependencies
timing 1000 executions of <class 'libfaketime.fake_time'>
0.021755 seconds

$ python benchmark.py freezegun
timing 1000 executions of <function freeze_time at 0x10aaa1140>
6.561472 seconds

Some brief details:

• linux and osx

• microsecond resolution

• accepts datetimes and strings that can be parsed by dateutil

• not threadsafe