Stuck on an issue?

Lightrun Answers was designed to reduce the constant googling that comes with debugging 3rd party libraries. It collects links to all the places you might be looking at while hunting down a tough bug.

And, if you’re still stuck at the end, we’re happy to hop on a call to see how we can help out.

Freezegun breaks isinstance() checks on existing objects.

See original GitHub issue

If you have a date object that was created before freezing time, you cannot then do an isinstance check against datetime.date:

>>> date = datetime.date.today()
>>> freezer = freeze_time('2011-01-01')
>>> freezer.start()
>>> isinstance(date, datetime.date)
False
>>>

This is because at the point you call the isinstance, the value of datetime.date is <class 'freezegun.api.FakeDate'>, of which date is not a subclass.

Issue Analytics

State:
Created 10 years ago
Comments:12 (6 by maintainers)

Top GitHub Comments

1reaction

schinckelcommented, Feb 16, 2018

I’m not sure. It seems that @spulec hasn’t been on GitHub much lately. He’s likely the only one who can merge, and push releases. It is possible to reference a git-commit in a requirements.txt: you may have to do that until he has time to merge/push.

0reactions

boxedcommented, Feb 19, 2019

I am also a contributor that can merge. Unfortunately I can’t cut releases to pypi at this time.

Top Results From Across the Web

Trying to mock datetime.date.today(), but not working

This one has advantage of not breaking type checking with isinstance(d, datetime.date) . import mock def fixed_today(today): from datetime import date class ...

python/typing - Gitter

Hello. I have a question on enum and typing. If I overload some function for each available enum values as parameter and then...

Digging into a Test Failure – A blog for Ted - Ted Mielczarek

I realized that if the database connection was created before any code imported the freezegun module the workaround freezegun was attempting to ...

How to work with dates and time with Python | Bloomberg LP

When trying to make things work with the datetime module, most Python users have faced a point when we resort to guess-and-check until...

pytest Documentation - Read the Docs

2.17 How to use pytest with an existing test suite . ... Note: Calling pytest.main() will result in importing your tests and any...