59 lines
1.3 KiB
Python
59 lines
1.3 KiB
Python
# Note: This file could use Python 3-only syntax, but at the moment this breaks
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# the coverage job on Python 2. Until we make it so that coverage can ignore
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# this file only on Python 2, we'll have to stick to 2/3-compatible syntax.
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try:
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import zoneinfo
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except ImportError:
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from backports import zoneinfo
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import datetime
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UTC = datetime.timezone.utc
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def get_timezone(key):
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try:
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return zoneinfo.ZoneInfo(key)
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except (ValueError, OSError):
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# TODO: Use `from e` when this file can use Python 3 syntax
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raise KeyError(key)
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def get_timezone_file(f, key=None):
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return zoneinfo.ZoneInfo.from_file(f, key=key)
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def get_fixed_offset_zone(offset):
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return datetime.timezone(datetime.timedelta(minutes=offset))
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def is_imaginary(dt):
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dt_rt = dt.astimezone(UTC).astimezone(dt.tzinfo)
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return not (dt == dt_rt)
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def is_ambiguous(dt):
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if is_imaginary(dt):
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return False
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wall_0 = dt
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wall_1 = dt.replace(fold=not dt.fold)
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# Ambiguous datetimes can only exist if the offset changes, so we don't
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# actually have to check whether dst() or tzname() are different.
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same_offset = wall_0.utcoffset() == wall_1.utcoffset()
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return not same_offset
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def enfold(dt, fold=1):
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if dt.fold != fold:
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return dt.replace(fold=fold)
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else:
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return dt
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def get_fold(dt):
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return dt.fold
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