1 files changed, 107 insertions, 0 deletions
diff --git a/src/tomli/_re.py b/src/tomli/_re.py
new file mode 100644
index 0000000..994bb74
--- /dev/null
+++ b/src/tomli/_re.py
@@ -0,0 +1,107 @@
+# 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
+
+from ._types import ParseFloat
+
+# E.g.
+# - 00:32:00.999999
+# - 00:32:00
+_TIME_RE_STR = r"([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9])(?:\.([0-9]{1,6})[0-9]*)?"
+
+RE_NUMBER = 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 = re.compile(_TIME_RE_STR)
+RE_DATETIME = 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)
+
+
+@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)