✨ Add parsing of pendulum_dt from unix time and non-strict parsing (#185)

* improve type checking in pendulum_dt.py
* added tests

Co-authored-by: 07pepa <pepe@wont_share.com>

Author: 07pepa

pydantic_extra_types/pendulum_dt.py

@@ -19,7 +19,17 @@
 from pydantic_core import PydanticCustomError, core_schema
 
 
-class DateTime(_DateTime):
+class DateTimeSettings(type):
+    def __new__(cls, name, bases, dct, **kwargs):  # type: ignore[no-untyped-def]
+        dct['strict'] = kwargs.pop('strict', True)
+        return super().__new__(cls, name, bases, dct)
+
+    def __init__(cls, name, bases, dct, **kwargs):  # type: ignore[no-untyped-def]
+        super().__init__(name, bases, dct)
+        cls.strict = kwargs.get('strict', True)
+
+
+class DateTime(_DateTime, metaclass=DateTimeSettings):
     """
     A `pendulum.DateTime` object. At runtime, this type decomposes into pendulum.DateTime automatically.
     This type exists because Pydantic throws a fit on unknown types.
@@ -54,7 +64,7 @@ def __get_pydantic_core_schema__(cls, source: Type[Any], handler: GetCoreSchemaH
         return core_schema.no_info_wrap_validator_function(cls._validate, core_schema.datetime_schema())
 
     @classmethod
-    def _validate(cls, value: Any, handler: core_schema.ValidatorFunctionWrapHandler) -> Any:
+    def _validate(cls, value: Any, handler: core_schema.ValidatorFunctionWrapHandler) -> 'DateTime':
         """
         Validate the datetime object and return it.
 
@@ -68,12 +78,10 @@ def _validate(cls, value: Any, handler: core_schema.ValidatorFunctionWrapHandler
         # if we are passed an existing instance, pass it straight through.
         if isinstance(value, (_DateTime, datetime)):
             return DateTime.instance(value)
-
-        # otherwise, parse it.
         try:
-            value = parse(value, exact=True)
-            if not isinstance(value, _DateTime):
-                raise ValueError(f'value is not a valid datetime it is a {type(value)}')
+            # probably the best way to have feature parity with
+            # https://docs.pydantic.dev/latest/api/standard_library_types/#datetimedatetime
+            value = handler(value)
             return DateTime(
                 value.year,
                 value.month,
@@ -84,8 +92,16 @@ def _validate(cls, value: Any, handler: core_schema.ValidatorFunctionWrapHandler
                 value.microsecond,
                 value.tzinfo,
             )
-        except Exception as exc:
-            raise PydanticCustomError('value_error', 'value is not a valid timestamp') from exc
+        except ValueError:
+            try:
+                value = parse(value, strict=cls.strict)
+                if isinstance(value, _DateTime):
+                    return DateTime.instance(value)
+                raise ValueError(f'value is not a valid datetime it is a {type(value)}')
+            except ValueError:
+                raise
+            except Exception as exc:
+                raise PydanticCustomError('value_error', 'value is not a valid datetime') from exc
 
 
 class Date(_Date):
@@ -123,7 +139,7 @@ def __get_pydantic_core_schema__(cls, source: Type[Any], handler: GetCoreSchemaH
         return core_schema.no_info_wrap_validator_function(cls._validate, core_schema.date_schema())
 
     @classmethod
-    def _validate(cls, value: Any, handler: core_schema.ValidatorFunctionWrapHandler) -> Any:
+    def _validate(cls, value: Any, handler: core_schema.ValidatorFunctionWrapHandler) -> 'Date':
         """
         Validate the date object and return it.
 
@@ -183,7 +199,7 @@ def __get_pydantic_core_schema__(cls, source: Type[Any], handler: GetCoreSchemaH
         return core_schema.no_info_wrap_validator_function(cls._validate, core_schema.timedelta_schema())
 
     @classmethod
-    def _validate(cls, value: Any, handler: core_schema.ValidatorFunctionWrapHandler) -> Any:
+    def _validate(cls, value: Any, handler: core_schema.ValidatorFunctionWrapHandler) -> 'Duration':
         """
         Validate the Duration object and return it.
 

pyproject.toml

@@ -119,6 +119,8 @@ filterwarnings = [
     'error',
     # This ignore will be removed when pycountry will drop py36 & support py311
     'ignore:::pkg_resources',
+    # This ignore will be removed when pendulum fixes https://github.com/sdispater/pendulum/issues/834
+    'ignore:datetime.datetime.utcfromtimestamp.*:DeprecationWarning'
 ]
 
 # configuring https://github.com/pydantic/hooky

tests/test_pendulum_dt.py

@@ -9,11 +9,21 @@
 
 UTC = tz.utc
 
+DtTypeAdapter = TypeAdapter(datetime)
+
 
 class DtModel(BaseModel):
     dt: DateTime
 
 
+class DateTimeNonStrict(DateTime, strict=False):
+    pass
+
+
+class DtModelNotStrict(BaseModel):
+    dt: DateTimeNonStrict
+
+
 class DateModel(BaseModel):
     d: Date
 
@@ -119,6 +129,91 @@ def test_pendulum_dt_from_serialized(dt):
     assert isinstance(model.dt, pendulum.DateTime)
 
 
+@pytest.mark.parametrize(
+    'dt',
+    [
+        pendulum.now().to_iso8601_string(),
+        pendulum.now().to_w3c_string(),
+        'Sat Oct 11 17:13:46 UTC 2003',  # date util parsing
+        pendulum.now().to_iso8601_string()[:5],  # actualy valid or pendulum.parse(dt, strict=False) would fail here
+    ],
+)
+def test_pendulum_dt_not_strict_from_serialized(dt):
+    """
+    Verifies that building an instance from serialized, well-formed strings decode properly.
+    """
+    dt_actual = pendulum.parse(dt, strict=False)
+    model = DtModelNotStrict(dt=dt)
+    assert model.dt == dt_actual
+    assert type(model.dt) is DateTime
+    assert isinstance(model.dt, pendulum.DateTime)
+
+
+@pytest.mark.parametrize(
+    'dt',
+    [
+        pendulum.now().to_iso8601_string(),
+        pendulum.now().to_w3c_string(),
+        1718096578,
+        1718096578.5,
+        -5,
+        -5.5,
+        float('-0'),
+        '1718096578',
+        '1718096578.5',
+        '-5',
+        '-5.5',
+        '-0',
+        '-0.0',
+        '+0.0',
+        '+1718096578.5',
+        float('-2e10') - 1.0,
+        float('2e10') + 1.0,
+        -2e10 - 1,
+        2e10 + 1,
+    ],
+)
+def test_pendulum_dt_from_str_unix_timestamp(dt):
+    """
+    Verifies that building an instance from serialized, well-formed strings decode properly.
+    """
+    dt_actual = pendulum.instance(DtTypeAdapter.validate_python(dt))
+    model = DtModel(dt=dt)
+    assert model.dt == dt_actual
+    assert type(model.dt) is DateTime
+    assert isinstance(model.dt, pendulum.DateTime)
+
+
+@pytest.mark.parametrize(
+    'dt',
+    [
+        1718096578,
+        1718096578.5,
+        -5,
+        -5.5,
+        float('-0'),
+        '1718096578',
+        '1718096578.5',
+        '-5',
+        '-5.5',
+        '-0',
+        '-0.0',
+        '+0.0',
+        '+1718096578.5',
+        float('-2e10') - 1.0,
+        float('2e10') + 1.0,
+        -2e10 - 1,
+        2e10 + 1,
+    ],
+)
+def test_pendulum_dt_from_str_unix_timestamp_is_utc(dt):
+    """
+    Verifies that without timezone information, it is coerced to UTC. As in pendulum
+    """
+    model = DtModel(dt=dt)
+    assert model.dt.tzinfo.tzname(model.dt) == 'UTC'
+
+
 @pytest.mark.parametrize(
     'd',
     [pendulum.now().date().isoformat(), pendulum.now().to_w3c_string(), pendulum.now().to_iso8601_string()],
@@ -155,22 +250,68 @@ def test_pendulum_duration_from_serialized(delta_t_str):
     assert isinstance(model.delta_t, pendulum.Duration)
 
 
-@pytest.mark.parametrize('dt', [None, 'malformed', pendulum.now().to_iso8601_string()[:5], 42, 'P10Y10M10D'])
+def get_invalid_dt_common():
+    return [
+        None,
+        'malformed',
+        'P10Y10M10D',
+        float('inf'),
+        float('-inf'),
+        'inf',
+        '-inf',
+        'INF',
+        '-INF',
+        '+inf',
+        'Infinity',
+        '+Infinity',
+        '-Infinity',
+        'INFINITY',
+        '+INFINITY',
+        '-INFINITY',
+        'infinity',
+        '+infinity',
+        '-infinity',
+        float('nan'),
+        'nan',
+        'NaN',
+        'NAN',
+        '+nan',
+        '-nan',
+    ]
+
+
+dt_strict = get_invalid_dt_common()
+dt_strict.append(pendulum.now().to_iso8601_string()[:5])
+
+
+@pytest.mark.parametrize(
+    'dt',
+    dt_strict,
+)
 def test_pendulum_dt_malformed(dt):
     """
-    Verifies that the instance fails to validate if malformed dt are passed.
+    Verifies that the instance fails to validate if malformed dt is passed.
     """
     with pytest.raises(ValidationError):
         DtModel(dt=dt)
 
 
-@pytest.mark.parametrize('date', [None, 'malformed', pendulum.today().to_iso8601_string()[:5], 42, 'P10Y10M10D'])
-def test_pendulum_date_malformed(date):
+@pytest.mark.parametrize('dt', get_invalid_dt_common())
+def test_pendulum_dt_non_strict_malformed(dt):
+    """
+    Verifies that the instance fails to validate if malformed dt are passed.
+    """
+    with pytest.raises(ValidationError):
+        DtModelNotStrict(dt=dt)
+
+
+@pytest.mark.parametrize('invalid_value', [None, 'malformed', pendulum.today().to_iso8601_string()[:5], 'P10Y10M10D'])
+def test_pendulum_date_malformed(invalid_value):
     """
     Verifies that the instance fails to validate if malformed date are passed.
     """
     with pytest.raises(ValidationError):
-        DateModel(d=date)
+        DateModel(d=invalid_value)
 
 
 @pytest.mark.parametrize(