Source code for hypothesis.extra.pytz

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# (, but it contains contributions by others. See
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This module provides :pypi:`pytz` timezones.

You can use this strategy to make
:py:func:`hypothesis.strategies.datetimes` and
:py:func:`hypothesis.strategies.times` produce timezone-aware values.

import datetime as dt

import pytz
from pytz.tzfile import StaticTzInfo

from hypothesis import strategies as st
from hypothesis.strategies._internal.utils import cacheable, defines_strategy

__all__ = ["timezones"]

[docs]@cacheable @defines_strategy() def timezones() -> st.SearchStrategy[dt.tzinfo]: """Any timezone in the Olsen database, as a pytz tzinfo object. This strategy minimises to UTC, or the smallest possible fixed offset, and is designed for use with :py:func:`hypothesis.strategies.datetimes`. """ all_timezones = [pytz.timezone(tz) for tz in pytz.all_timezones] # Some timezones have always had a constant offset from UTC. This makes # them simpler than timezones with daylight savings, and the smaller the # absolute offset the simpler they are. Of course, UTC is even simpler! static: list = [pytz.UTC] static += sorted( (t for t in all_timezones if isinstance(t, StaticTzInfo)), key=lambda tz: abs(tz.utcoffset(dt.datetime(2000, 1, 1))), ) # Timezones which have changed UTC offset; best ordered by name. dynamic = [tz for tz in all_timezones if tz not in static] return st.sampled_from(static + dynamic)