Body() fields are ignored if they are mapped to same variable name in any dependency

[peku33]

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Example Code

from typing import Awaitable, Callable

from fastapi import APIRouter, Body, Depends


api_router = APIRouter()


def _make_field(name: str) -> Callable[..., Awaitable[str]]:
    async def _inner(
        value: str = Body(..., alias=name),  # <<<<<<<<<<<<<< HERE
        # ^^^ HERE
    ) -> str:
        return value

    return _inner


@api_router.post("/test1")
async def test(
    _field_0: str = Body(..., alias="field_0"),
    _field_1: str = Depends(_make_field("field_1")),
    _field_2: str = Depends(_make_field("field_2")),
) -> None:
    pass

Description

When two ore more Body() fields are added indirectly and are bound to the same variable name, only the last one will be visible in docs. Aliasing them will not make any difference.

The example above will show only field_0 and field_2 in the docs, while field_1 is missing.
When trying to execute the endpoint it will operate correctly.

If there are two different dependencies using internally the same variable name for different body values, it will also not work.

Operating System

Other

Operating System Details

No response

FastAPI Version

0.74.1

Python Version

3.10.1

Additional Context

No response