class FormModelOptionalValidationAlias(BaseModel):
    p: Optional[str] = Field(None, validation_alias="p_val_alias")


@app.post(
    "/model-optional-validation-alias", operation_id="model_optional_validation_alias"
)
def read_model_optional_validation_alias(
    p: Annotated[FormModelOptionalValidationAlias, Form()],
):
    return {"p": p.p}


@pytest.mark.parametrize(
    "path",