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# SPDX-License-Identifier: MIT
# SPDX-FileCopyrightText: 2021 Taneli Hukkinen
# Licensed to PSF under a Contributor Agreement.
from __future__ import annotations
from datetime import date, datetime, time, timedelta, timezone, tzinfo
from functools import lru_cache
import re
from typing import Any, Final
from ._types import ParseFloat
# E.g.
# - 00:32:00.999999
# - 00:32:00
_TIME_RE_STR: Final = (
r"([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9])(?:\.([0-9]{1,6})[0-9]*)?"
)
RE_NUMBER: Final = re.compile(
r"""
0
(?:
x[0-9A-Fa-f](?:_?[0-9A-Fa-f])* # hex
|
b[01](?:_?[01])* # bin
|
o[0-7](?:_?[0-7])* # oct
)
|
[+-]?(?:0|[1-9](?:_?[0-9])*) # dec, integer part
(?P<floatpart>
(?:\.[0-9](?:_?[0-9])*)? # optional fractional part
(?:[eE][+-]?[0-9](?:_?[0-9])*)? # optional exponent part
)
""",
flags=re.VERBOSE,
)
RE_LOCALTIME: Final = re.compile(_TIME_RE_STR)
RE_DATETIME: Final = re.compile(
rf"""
([0-9]{{4}})-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01]) # date, e.g. 1988-10-27
(?:
[Tt ]
{_TIME_RE_STR}
(?:([Zz])|([+-])([01][0-9]|2[0-3]):([0-5][0-9]))? # optional time offset
)?
""",
flags=re.VERBOSE,
)
def match_to_datetime(match: re.Match) -> datetime | date:
"""Convert a `RE_DATETIME` match to `datetime.datetime` or `datetime.date`.
Raises ValueError if the match does not correspond to a valid date
or datetime.
"""
(
year_str,
month_str,
day_str,
hour_str,
minute_str,
sec_str,
micros_str,
zulu_time,
offset_sign_str,
offset_hour_str,
offset_minute_str,
) = match.groups()
year, month, day = int(year_str), int(month_str), int(day_str)
if hour_str is None:
return date(year, month, day)
hour, minute, sec = int(hour_str), int(minute_str), int(sec_str)
micros = int(micros_str.ljust(6, "0")) if micros_str else 0
if offset_sign_str:
tz: tzinfo | None = cached_tz(
offset_hour_str, offset_minute_str, offset_sign_str
)
elif zulu_time:
tz = timezone.utc
else: # local date-time
tz = None
return datetime(year, month, day, hour, minute, sec, micros, tzinfo=tz)
# No need to limit cache size. This is only ever called on input
# that matched RE_DATETIME, so there is an implicit bound of
# 24 (hours) * 60 (minutes) * 2 (offset direction) = 2880.
@lru_cache(maxsize=None)
def cached_tz(hour_str: str, minute_str: str, sign_str: str) -> timezone:
sign = 1 if sign_str == "+" else -1
return timezone(
timedelta(
hours=sign * int(hour_str),
minutes=sign * int(minute_str),
)
)
def match_to_localtime(match: re.Match) -> time:
hour_str, minute_str, sec_str, micros_str = match.groups()
micros = int(micros_str.ljust(6, "0")) if micros_str else 0
return time(int(hour_str), int(minute_str), int(sec_str), micros)
def match_to_number(match: re.Match, parse_float: ParseFloat) -> Any:
if match.group("floatpart"):
return parse_float(match.group())
return int(match.group(), 0)
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