^{Originally posted by MartinAchtnerAA September 19, 2024}

First Check

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Example Code

from typing import Annotated, Literal, Optional

from fastapi import FastAPI, Form
from fastapi.testclient import TestClient

app = FastAPI()

@app.post("/")
async def read_main(
    attribute : Annotated[Optional[Literal["abc", "def"]], Form()]
):
    print(attribute)


client = TestClient(app)


data = {}
data["attribute"] = None

response = client.post("/", data=data)
print(response.content)
assert response.status_code == 200

Description

In FastAPI 0.113 .0 the above code passes.
Since version 0.114.0 the response is a 422 status code with error message '{"detail":[{"type":"literal_error","loc":["body","attribute"],"msg":"Input should be 'abc' or 'def'","input":"","ctx":{"expected":"'abc' or 'def'"}}]}'

Operating System

macOS

Operating System Details

No response

FastAPI Version

0.114.0

Pydantic Version

2.9.1

Python Version

3.12.3

Additional Context

No response