[Python] Add test case for flatten model initialization to check compatibility

.chronus/changes/python-flatten-model-initialization-test-2025-11-1-8-33-43.md

@@ -0,0 +1,7 @@
+---
+changeKind: internal
+packages:
+  - "@typespec/http-client-python"
+---
+
+Add test case for flatten model initialization to check compatibility

packages/http-client-python/generator/test/azure/mock_api_tests/test_model_base_flatten_compatibility.py

@@ -0,0 +1,181 @@
+# ------------------------------------
+# Copyright (c) Microsoft Corporation.
+# Licensed under the MIT License.
+# ------------------------------------
+import datetime
+from typing import (
+    Any,
+    Mapping,
+    overload,
+)
+
+from specs.azure.clientgenerator.core.flattenproperty._utils.model_base import (
+    Model,
+    rest_field,
+)
+
+
+class ModelProperty(Model):
+    """This is a test model."""
+
+    value: str = rest_field()
+    """Required."""
+
+    @overload
+    def __init__(
+        self,
+        *,
+        value: str,
+    ) -> None: ...
+
+    @overload
+    def __init__(self, mapping: Mapping[str, Any]) -> None:
+        """
+        :param mapping: raw JSON to initialize the model.
+        :type mapping: Mapping[str, Any]
+        """
+
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
+        super().__init__(*args, **kwargs)
+
+
+class ChildModel(Model):
+    """This is the child model to be flattened.
+
+    :ivar description: Required.
+    :vartype description: str
+    :ivar age: Required.
+    :vartype age: int
+    """
+
+    description: str = rest_field()
+    """Required."""
+    age: int = rest_field()
+    """Required."""
+    model_property: "ModelProperty" = rest_field(name="modelProperty")
+    """Required."""
+    datetime_default: datetime.datetime = rest_field(name="datetimeDefault")
+    datetime_rfc3339: datetime.datetime = rest_field(name="datetimeRfc3339", format="rfc3339")
+    datetime_rfc7231: datetime.datetime = rest_field(name="datetimeRfc7231", format="rfc7231")
+    datetime_unix_timestamp: datetime.datetime = rest_field(name="datetimeUnixTimestamp", format="unix-timestamp")
+
+    @overload
+    def __init__(
+        self,
+        *,
+        description: str,
+        age: int,
+        model_property: "ModelProperty",
+        datetime_default: datetime.datetime,
+        datetime_rfc3339: datetime.datetime,
+        datetime_rfc7231: datetime.datetime,
+        datetime_unix_timestamp: datetime.datetime,
+    ) -> None: ...
+
+    @overload
+    def __init__(self, mapping: Mapping[str, Any]) -> None:
+        """
+        :param mapping: raw JSON to initialize the model.
+        :type mapping: Mapping[str, Any]
+        """
+
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
+        super().__init__(*args, **kwargs)
+
+
+class FlattenModel(Model):
+    """This is the model with one level of flattening."""
+
+    name: str = rest_field()
+    """Required."""
+    properties: "ChildModel" = rest_field()
+    """Required."""
+
+    __flattened_items = [
+        "description",
+        "age",
+        "model_property",
+        "datetime_default",
+        "datetime_rfc3339",
+        "datetime_rfc7231",
+        "datetime_unix_timestamp",
+    ]
+
+    @overload
+    def __init__(
+        self,
+        *,
+        name: str,
+        properties: "ChildModel",
+    ) -> None: ...
+
+    @overload
+    def __init__(self, mapping: Mapping[str, Any]) -> None:
+        """
+        :param mapping: raw JSON to initialize the model.
+        :type mapping: Mapping[str, Any]
+        """
+
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
+        _flattened_input = {k: kwargs.pop(k) for k in kwargs.keys() & self.__flattened_items}
+        super().__init__(*args, **kwargs)
+        for k, v in _flattened_input.items():
+            setattr(self, k, v)
+
+    def __getattr__(self, name: str) -> Any:
+        if name in self.__flattened_items:
+            if self.properties is None:
+                return None
+            return getattr(self.properties, name)
+        raise AttributeError(f"'{self.__class__.__name__}' object has no attribute '{name}'")
+
+    def __setattr__(self, key: str, value: Any) -> None:
+        if key in self.__flattened_items:
+            if self.properties is None:
+                self.properties = self._attr_to_rest_field["properties"]._class_type()
+            setattr(self.properties, key, value)
+        else:
+            super().__setattr__(key, value)
+
+
+def test_model_initialization():
+    model = FlattenModel(
+        name="test",
+        description="a description",
+        age=30,
+        model_property=ModelProperty(value="test value"),
+        datetime_default=datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc),
+        datetime_rfc3339=datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc),
+        datetime_rfc7231=datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc),
+        datetime_unix_timestamp=datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc),
+    )
+
+    assert model.name == "test"
+
+    assert model.description == "a description"
+    assert model.properties.description == "a description"
+
+    assert model.age == 30
+    assert model.properties.age == 30
+
+    assert model.model_property.value == "test value"
+    assert model.properties.model_property == ModelProperty(value="test value")
+    assert model.properties.model_property.value == "test value"
+
+    assert model.datetime_default == datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc)
+    assert model.properties.datetime_default == datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc)
+    assert model.properties["datetimeDefault"] == "2023-01-12T00:00:00Z"
+
+    assert model.datetime_rfc3339 == datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc)
+    assert model.properties.datetime_rfc3339 == datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc)
+    assert model.properties["datetimeRfc3339"] == "2023-01-12T00:00:00Z"
+
+    assert model.datetime_rfc7231 == datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc)
+    assert model.properties.datetime_rfc7231 == datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc)
+    assert model.properties["datetimeRfc7231"] == "Thu, 12 Jan 2023 00:00:00 GMT"
+
+    assert model.datetime_unix_timestamp == datetime.datetime(2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc)
+    assert model.properties.datetime_unix_timestamp == datetime.datetime(
+        2023, 1, 12, 0, 0, 0, tzinfo=datetime.timezone.utc
+    )
+    assert model.properties["datetimeUnixTimestamp"] == 1673481600