FakeChain Class — langchain Architecture

Architecture documentation for the FakeChain class in test_file.py from the langchain codebase.

Class python

Entity Profile

Dependency Diagram

graph TD
  82b29701_3ebe_8165_dfa2_2528e0594b83["FakeChain"]
  f3cef70e_11b0_61c9_7ec0_7308f4b45056["Chain"]
  82b29701_3ebe_8165_dfa2_2528e0594b83 -->|extends| f3cef70e_11b0_61c9_7ec0_7308f4b45056
  208c1f71_5b87_0580_ea58_7fe3e9a67452["test_file.py"]
  82b29701_3ebe_8165_dfa2_2528e0594b83 -->|defined in| 208c1f71_5b87_0580_ea58_7fe3e9a67452
  ff7d9c65_9d41_a93d_95d5_b8d2f0389788["input_keys()"]
  82b29701_3ebe_8165_dfa2_2528e0594b83 -->|method| ff7d9c65_9d41_a93d_95d5_b8d2f0389788
  fe3d10c8_2b4c_6b03_d5bc_6cca48809bba["output_keys()"]
  82b29701_3ebe_8165_dfa2_2528e0594b83 -->|method| fe3d10c8_2b4c_6b03_d5bc_6cca48809bba
  55f4d281_295f_6880_d29c_3f1b8b8963b9["_call()"]
  82b29701_3ebe_8165_dfa2_2528e0594b83 -->|method| 55f4d281_295f_6880_d29c_3f1b8b8963b9

Relationship Graph

Source Code

libs/langchain/tests/unit_tests/callbacks/test_file.py lines 11–34

class FakeChain(Chain):
    """Fake chain class for testing purposes."""

    be_correct: bool = True
    the_input_keys: list[str] = ["foo"]
    the_output_keys: list[str] = ["bar"]

    @property
    def input_keys(self) -> list[str]:
        """Input keys."""
        return self.the_input_keys

    @property
    def output_keys(self) -> list[str]:
        """Output key of bar."""
        return self.the_output_keys

    @override
    def _call(
        self,
        inputs: dict[str, str],
        run_manager: CallbackManagerForChainRun | None = None,
    ) -> dict[str, str]:
        return {"bar": "bar"}