Breaking change with path parameters when updating to pydantic>=2 from pydantic<2

[ThirVondukr]

First Check

• I added a very descriptive title here.
• I used the GitHub search to find a similar question 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

from uuid import UUID

from fastapi import FastAPI

app = FastAPI()


@app.get("/int/{path}")
async def int_(path: int | str):
    return str(type(path))


@app.get("/uuid/{path}")
async def uuid_(path: UUID | str):
    return str(type(path))

Description

With pydantic<2 parameters are correctly parsed as int and UUID if an appropriate string is passed, with pydantic 2 they're always interpreted as str, I presume this will work the same way with all other types that you can pass into path parameters.
I also observed the same behavior with query, so I assume it behaves the same way with all FastAPI parameters (headers, body, etc).

Operating System

Windows

Operating System Details

No response

FastAPI Version

0.110.0

Pydantic Version

1.10.14 / 2.6.3

Python Version

Python 3.11.5

Additional Context

No response

[Kludex]

• Thanks. Breaking change with path parameters when updating to pydantic>=2 from pydantic<2 #11251