First Check

• I added a very descriptive title to this issue.
• I used the GitHub search to find a similar issue and didn't find it.
• I searched the FastAPI documentation, with the integrated search.
• I already searched in Google "How to X in FastAPI" and didn't find any information.
• I already read and followed all the tutorial in the docs and didn't find an answer.
• I already checked if it is not related to FastAPI but to Pydantic.
• I already checked if it is not related to FastAPI but to Swagger UI.
• I already checked if it is not related to FastAPI but to ReDoc.

Commit to Help

• I commit to help with one of those options 👆

Example Code

See the PR I opened with a fix: #4267 It includes a test case that describes the use case.

Description

When specifying parameters in openapi_extras for an endpoint, they will overwrite the existing query parameters with the extra parameters, rather than appending the parameters to the spec. This is due to deep_dict_update in utils.py overwriting list types rather than merging them together.

I have created a PR already which has a fix and adds a test case: #4267
These updates change the behavior to merge parameters together rather than overwriting.

If y'all agree that this seems like a bug, I'd appreciate a review on the PR. Thanks in advance! 😄

Operating System

macOS

Operating System Details

No response

FastAPI Version

0.70.0

Python Version

Python 3.9.7

Additional Context

No response