nolar / looptime

Time dilation & contraction in asyncio event loops (in tests)

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• 🐍 Python Developer.
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looptime's Issues

Is it possible to affect an entire python process with looptime.

For our use case we need to speed up an entire python process using an event loop architecture. Would it be possible to use looptime to speed up the entire process?

Willing to put some work into making this possible, would really appreciate being pointed in the right direction.

Bug: TimerHandle.when() isn't properly mocked?

Long story short

It seems that possibly TimerHandle#when isn't properly mocked? I'm trying to write a reschedulable timer, so that if you try to rescheduled it for shorter than the original request it fails, but you can easily extend it. This code was failing and adding some logging reveals very unexpected results around the timing values.

Description

Code in question:

def resuspend_keys(timeout):
    if is_suspended():
        loop = asyncio.get_event_loop()
        until_wake = _suspend_timer.when() - loop.time()
        if timeout < until_wake:
            return

    _suspend_timer.cancel()
    suspend_keys(timeout)

IE: find the currently planned execution time, how far into the future it is... and reschedule (or not depending)... but in logging both timer.when() and loop.time() I get output like:

(--) when 1945811.476378708
(--) loop time 2.0
(--) 1945809.476378708 until wake

It looks like loop time is being mocked as the tests moved thru time (I have a await asyncio.sleep(2)) but that the when() call is still returning some actual timestamp from the live running system.

If you need any additional details, please ask.