`anyOf` in responses generates invalid body parser

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#1,263 opened on Jun 3, 2025 0 comments 5 reactions 0 assignees View on GitHub

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Assessment

Difficulty: 4/5
Estimated time: 3-5 days
Newbie friendliness: 38/100

Issue type: Bug
Clarity: Needs clarification
Activity status: Stale
Tech stack: openapi, python
Domain: api, tooling

Research direction

Start with the OpenAPI Spec File linked in the issue and reproduce the generated _parse_response_200 example for a response schema using anyOf. Compare the generated parser branches and verify that the output is valid and can parse both the fixed-value and Response200 alternatives.

Written by the indexing model from the issue text.

Description

Describe the bug
When a response media type has an anyOf schema, the generated code does not parse it properly/is not valid. (see add'l context)
OpenAPI Spec File
https://gist.github.com/nkrishnaswami/8c4a2068d8ac59cab153136a6069b44d

Desktop (please complete the following information):

OS: macOS 15.6
Python Version: 3.12.8
openapi-python-client version: git revision 13bf2e8

Additional context

        def _parse_response_200(data: object) -> Union["Response200", Literal["Why have a fixed response? I dunno"]]:
            response_200_type_0 = cast(Literal["Why have a fixed response? I dunno"], data)
            if response_200_type_0 != "Why have a fixed response? I dunno":
                raise ValueError(
                    f"response_200_type_0 must match const 'Why have a fixed response? I dunno', got '{response_200_type_0}'"
                )
            return response_200_type_0
            if not isinstance(data, dict):
                raise TypeError()
            response_200_type_1 = Response200.from_dict(data)

            return response_200_type_1

Dominant language: Python
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Merged PRs (30d): 1

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