test__is_field_useful() — langchain Function Reference

Architecture documentation for the test__is_field_useful() function in test_serializable.py from the langchain codebase.

Function python LangChainCore MessageInterface

Entity Profile

LangChainCore→ MessageInterface→ test__is_field_useful() — langchain Function Reference

Dependency Diagram

graph TD
  4cdadfec_089e_56a7_9d03_d639c91924aa["test__is_field_useful()"]
  d90477e3_b806_4058_daf0_8495f08436d6["test_serializable.py"]
  4cdadfec_089e_56a7_9d03_d639c91924aa -->|defined in| d90477e3_b806_4058_daf0_8495f08436d6
  style 4cdadfec_089e_56a7_9d03_d639c91924aa fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/core/tests/unit_tests/load/test_serializable.py lines 103–133

def test__is_field_useful() -> None:
    class ArrayObj:
        def __bool__(self) -> bool:
            msg = "Truthiness can't be determined"
            raise ValueError(msg)

        def __eq__(self, other: object) -> bool:
            return self  # type: ignore[return-value]

        __hash__ = None  # type: ignore[assignment]

    default_x = ArrayObj()
    default_y = NonBoolObj()

    class Foo(Serializable):
        x: ArrayObj = Field(default=default_x)
        y: NonBoolObj = Field(default=default_y)
        # Make sure works for fields without default.
        z: ArrayObj

        model_config = ConfigDict(
            arbitrary_types_allowed=True,
        )

    foo = Foo(x=ArrayObj(), y=NonBoolObj(), z=ArrayObj())
    assert _is_field_useful(foo, "x", foo.x)
    assert _is_field_useful(foo, "y", foo.y)

    foo = Foo(x=default_x, y=default_y, z=ArrayObj())
    assert not _is_field_useful(foo, "x", foo.x)
    assert not _is_field_useful(foo, "y", foo.y)