Test fails on some days

[dotlambda]

My local time is

Tue Feb 28 11:54:04 AM PST 2023

and the tests fail with

============================= test session starts ==============================
platform linux -- Python 3.10.10, pytest-7.2.0, pluggy-1.0.0
rootdir: /build/tempora-5.1.0, configfile: pytest.ini
plugins: freezegun-0.4.2
collected 42 items

tempora/__init__.py ..........F.                                         [ 28%]
tempora/schedule.py ...                                                  [ 35%]
tempora/timing.py .....                                                  [ 47%]
tempora/utc.py .                                                         [ 50%]
tempora/tests/test_schedule.py ...................                       [ 95%]
tempora/tests/test_timing.py ..                                          [100%]

=================================== FAILURES ===================================
______________________ [doctest] tempora.parse_timedelta _______________________
382
383     >>> parse_timedelta('1 year, 1 month')
384     datetime.timedelta(days=395, seconds=58685)
385
386     Note that months and years strict intervals, not aligned
387     to a calendar:
388
389     >>> now = datetime.datetime.now()
390     >>> later = now + parse_timedelta('1 year')
391     >>> diff = later.replace(year=now.year) - now
UNEXPECTED EXCEPTION: ValueError('day is out of range for month')
Traceback (most recent call last):
  File "/nix/store/iw1vmh509hcbby8dbpsaanbri4zsq7dj-python3-3.10.10/lib/python3.10/doctest.py", line 1350, in __run
    exec(compile(example.source, filename, "single",
  File "<doctest tempora.parse_timedelta[7]>", line 1, in <module>
ValueError: day is out of range for month
/build/tempora-5.1.0/tempora/__init__.py:391: UnexpectedException
=========================== short test summary info ============================
FAILED tempora/__init__.py::tempora.parse_timedelta
========================= 1 failed, 41 passed in 1.53s =========================

[DimStar77]

Looking at the code, the issue is that 'next year is a leap year': the test does:

now=datetime.datetime.now()
print(now)
later = now + datetime.timedelta(days=365)
print(later)
diff = later.replace(year=now.year) - now

>>> now=datetime.datetime.now()
>>> print(now)
2023-03-01 10:17:55.056591
>>> later = now + datetime.timedelta(days=365)
>>> print(later)
2024-02-29 10:17:55.056591

There we can already see that 'diff' can't be valid if we replace the year from 'later (2024) with this year (2023).

[jaraco]

Ha. Okay. So that test would fail for about 20k seconds when run one year before the leap day.