Examples

Skip timeouts

Tests are deterministic and take no time with time travel. For example:

with TimeTravel():
    assert time.time() == 86400
    time.sleep(200)
    assert time.time() == 86600

with TimeTravel(modules_to_patch=__name__):
    assert datetime.today() == datetime.fromtimestamp(86400)
    time.sleep(250)
    assert datetime.today() == datetime.fromtimestamp(86650)

import module1
import module2

with TimeTravel(modules_to_patch=['module1', 'module2']) as time_machine:
    time_machine.set_time(100000)
    module1.very_long_method()
    module2.time_sensitive_method()

Patching I/O events modules

With time-travel you can fake future events for I/O modules:

with TimeTravel() as t:
    sock = socket.socket()
    t.add_future_event(2, sock, t.event_types.select.WRITE)

    now = t.clock.time
    assert select.select([], [sock], []) == ([], [sock], [])
    assert time.time() == now + 2
    assert datetime_cls.today() == datetime_cls.fromtimestamp(now + 2)

Or using poll (for supported platforms only):

with TimeTravel() as t:
    sock = socket.socket()
    t.add_future_event(2, sock, select.POLLIN)

    poll = select.poll()
    poll.register(sock, select.POLLIN | select.POLLOUT)

    now = t.clock.time
    assert poll.poll() == [(sock, select.POLLIN)]
    assert time.time() == now + 2