Remove iso8601 dependency

.github/workflows/ci.yml

@@ -248,8 +248,26 @@ jobs:
           if-no-files-found: error
           include-hidden-files: true
 
+  test-windows-accel:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v6
+      - uses: actions/setup-python@v6
+        with:
+          python-version: "3.14"
+      - uses: astral-sh/setup-uv@08807647e7069bb48b6ef5acd8ec9567f424441b
+      - name: Install accel extra
+        run: uv sync --frozen --extra accel --group test
+      - name: Verify ciso8601 acceleration
+        run: |
+          uv run --frozen python -c "import ciso8601; import tortoise.timezone as tz; assert tz.parse_datetime is ciso8601.parse_datetime"
+      - name: Test parser compatibility
+        run: |
+          uv pip uninstall ciso8601
+          uv run --no-sync pytest -n auto --cov=tortoise --cov-append --cov-branch --tb=native -q tests/fields/test_time.py
+
   coverage:
-    needs: [test-sqlite, test-postgres, test-mysql, test-mssql]
+    needs: [test-sqlite, test-postgres, test-mysql, test-mssql, test-windows-accel]
     runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v6

pyproject.toml

@@ -9,7 +9,6 @@ dynamic = ["version"]
 requires-python = ">=3.10"
 dependencies = [
     "pypika-tortoise (>=0.6.5,<1.0.0)",
-    "iso8601 (>=2.1.0,<3.0.0); python_version < '4.0'",
     "aiosqlite (>=0.16.0,<1.0.0)",
     "anyio",
     "tomlkit (>=0.11.4,<1.0.0); python_version < '3.11'",
@@ -46,7 +45,7 @@ ptpython = [
     "ptpython>=3.0.0",
 ]
 accel = [
-    "ciso8601; sys_platform != 'win32' and implementation_name == 'cpython'",
+    "ciso8601; implementation_name == 'cpython'",
     "uvloop; sys_platform != 'win32' and implementation_name == 'cpython'",
     "orjson",
 ]

tests/fields/test_time.py

@@ -7,7 +7,6 @@
 from zoneinfo import ZoneInfoNotFoundError
 
 import pytest
-from iso8601 import ParseError
 
 from tests import testmodels
 from tortoise import fields, timezone
@@ -673,7 +672,7 @@ async def test_date_str(db):
     obj0 = await model.create(date="2020-08-17")
     obj1 = await model.get(date="2020-08-17")
     assert obj0.date == obj1.date
-    with pytest.raises((ParseError, ValueError)):
+    with pytest.raises(ValueError):
         await model.create(date="2020-08-xx")
     await model.filter(date="2020-08-17").update(date="2020-08-18")
     obj2 = await model.get(date="2020-08-18")
@@ -758,6 +757,45 @@ def test_zoneinfo():
         parse_timezone("Invalid/Zonename")
 
 
+def test_parse_datetime_fallback():
+    assert timezone._parse_datetime("2020-08-17") == datetime(2020, 8, 17)
+    assert timezone._parse_datetime("2020-08-17T00:00:00Z") == datetime(2020, 8, 17, tzinfo=UTC)
+    assert timezone._parse_datetime("2020-230T12:34:56Z") == datetime(
+        2020, 8, 17, 12, 34, 56, tzinfo=UTC
+    )
+    assert timezone._parse_datetime("2020-230t12:34:56") == datetime(2020, 8, 17, 12, 34, 56)
+    assert timezone._parse_datetime("2020230T123456") == datetime(2020, 8, 17, 12, 34, 56)
+
+
+@pytest.mark.parametrize(
+    "value",
+    [
+        "2020-08-17",
+        "20200817",
+        "2020-08-17T12:34:56",
+        "2020-08-17t12:34:56",
+        "2020-08-17 12:34:56",
+        "20200817T123456",
+        "2020-08-17T12:34:56Z",
+        "2020-08-17T12:34:56z",
+        "2020-08-17T12:34:56+08",
+        "2020-08-17T12:34:56+0800",
+        "2020-08-17T12:34:56+08:00",
+        "2020-W34-1",
+        "2020W341",
+        "2020-230",
+        "2020230",
+        "2020-230T12:34:56",
+        "2020-230t12:34:56",
+        "2020230T123456",
+    ],
+)
+def test_parse_datetime_fallback_matches_ciso8601(value):
+    ciso8601 = pytest.importorskip("ciso8601")
+
+    assert timezone._parse_datetime(value) == ciso8601.parse_datetime(value)
+
+
 def test_timezone(tz_env):
     os.environ["USE_TZ"] = "True"
     timezone._reset_timezone_cache()

tortoise/backends/oracle/client.py

@@ -1,17 +1,9 @@
 from __future__ import annotations
 
 import datetime
-import functools
 from typing import TYPE_CHECKING, Any, SupportsInt, cast
 
 import pyodbc
-
-try:
-    from ciso8601 import parse_datetime
-except ImportError:  # pragma: nocoverage
-    from iso8601 import parse_date
-
-    parse_datetime = functools.partial(parse_date, default_timezone=None)
 from pypika_tortoise import OracleQuery
 
 from tortoise.backends.base.client import (
@@ -28,7 +20,7 @@
 )
 from tortoise.backends.oracle.executor import OracleExecutor
 from tortoise.backends.oracle.schema_generator import OracleSchemaGenerator
-from tortoise.timezone import UTC, get_use_tz
+from tortoise.timezone import UTC, get_use_tz, parse_datetime
 
 if TYPE_CHECKING:  # pragma: nocoverage
     import asyncodbc  # pylint: disable=W0611

tortoise/fields/data.py

@@ -18,16 +18,15 @@
 from tortoise import timezone
 from tortoise.exceptions import ConfigurationError, FieldError
 from tortoise.fields.base import Field
-from tortoise.timezone import get_default_timezone, get_timezone, get_use_tz, localtime
+from tortoise.timezone import (
+    get_default_timezone,
+    get_timezone,
+    get_use_tz,
+    localtime,
+    parse_datetime,
+)
 from tortoise.validators import MaxLengthValidator
 
-try:
-    from ciso8601 import parse_datetime
-except ImportError:  # pragma: nocoverage
-    from iso8601 import parse_date
-
-    parse_datetime = functools.partial(parse_date, default_timezone=None)
-
 try:
     from pydantic import BaseModel as _PydanticBaseModel
     from pydantic._internal._model_construction import ModelMetaclass as _PydanticModelMetaclass

tortoise/timezone.py

@@ -2,7 +2,9 @@
 
 import functools
 import os
+import re
 import sys
+from collections.abc import Callable
 from datetime import datetime, time, tzinfo
 from zoneinfo import ZoneInfo as _ZoneInfo
 from zoneinfo import ZoneInfoNotFoundError
@@ -14,6 +16,29 @@
 
     UTC = timezone.utc
 
+_ORDINAL_DATE_RE = re.compile(r"^(\d{4})-?(\d{3})(?=$|[Tt ])")
+
+
+def _parse_datetime(value: str) -> datetime:
+    if value.endswith(("Z", "z")):
+        value = f"{value[:-1]}+00:00"
+    try:
+        return datetime.fromisoformat(value)
+    except ValueError:
+        # Match ordinal dates accepted by ciso8601, such as 2020-230 or 2020230.
+        if m := _ORDINAL_DATE_RE.match(value):
+            date_format = "%Y-%j" if "-" in m.group() else "%Y%j"
+            date_value = datetime.strptime(m.group(), date_format).date()
+            return datetime.fromisoformat(f"{date_value.isoformat()}{value[m.end() :]}")
+        raise
+
+
+parse_datetime: Callable[[str], datetime]
+try:
+    from ciso8601 import parse_datetime as parse_datetime
+except ImportError:  # pragma: nocoverage
+    parse_datetime = _parse_datetime
+
 
 class ZoneInfo(_ZoneInfo):
     @property