@app.get("/optional-validation-alias")
def read_optional_validation_alias(
    p: Annotated[str | None, Header(validation_alias="p_val_alias")] = None,
):
    return {"p": p}


class HeaderModelOptionalValidationAlias(BaseModel):
    p: str | None = Field(None, validation_alias="p_val_alias")


@app.get("/model-optional-validation-alias")
def read_model_optional_validation_alias(

@app.get("/optional-validation-alias")
def read_optional_validation_alias(
    p: Annotated[str | None, Cookie(validation_alias="p_val_alias")] = None,
):
    return {"p": p}


class CookieModelOptionalValidationAlias(BaseModel):
    p: str | None = Field(None, validation_alias="p_val_alias")


@app.get("/model-optional-validation-alias")
def read_model_optional_validation_alias(

@app.get("/optional-list-validation-alias")
def read_optional_list_validation_alias(
    p: Annotated[list[str] | None, Header(validation_alias="p_val_alias")] = None,
):
    return {"p": p}


class HeaderModelOptionalListValidationAlias(BaseModel):
    p: list[str] | None = Field(None, validation_alias="p_val_alias")


@app.get("/model-optional-list-validation-alias")
def read_model_optional_list_validation_alias(

@app.get("/optional-validation-alias")
def read_optional_validation_alias(
    p: Annotated[str | None, Query(validation_alias="p_val_alias")] = None,
):
    return {"p": p}


class QueryModelOptionalValidationAlias(BaseModel):
    p: str | None = Field(None, validation_alias="p_val_alias")


@app.get("/model-optional-validation-alias")
def read_model_optional_validation_alias(

from pydantic import BaseModel, ConfigDict, Field


@pytest.fixture(name="client")
def get_client():
    app = FastAPI()

    class ModelWithRef(BaseModel):
        ref: str = Field(validation_alias="$ref", serialization_alias="$ref")
        model_config = ConfigDict(validate_by_alias=True, serialize_by_alias=True)

    @app.get("/", response_model=ModelWithRef)
    async def read_root() -> Any:

@app.post("/optional-validation-alias", operation_id="optional_validation_alias")
def read_optional_validation_alias(
    p: Annotated[str | None, Form(validation_alias="p_val_alias")] = None,
):
    return {"p": p}


class FormModelOptionalValidationAlias(BaseModel):
    p: str | None = Field(None, validation_alias="p_val_alias")


@app.post(
    "/model-optional-validation-alias", operation_id="model_optional_validation_alias"
)

@app.get("/optional-list-validation-alias")
def read_optional_list_validation_alias(
    p: Annotated[list[str] | None, Query(validation_alias="p_val_alias")] = None,
):
    return {"p": p}


class QueryModelOptionalListValidationAlias(BaseModel):
    p: list[str] | None = Field(None, validation_alias="p_val_alias")


@app.get("/model-optional-list-validation-alias")
def read_model_optional_list_validation_alias(

@app.get("/required-validation-alias/{p_val_alias}")
def read_required_validation_alias(
    p: Annotated[str, Path(validation_alias="p_val_alias")],
):
    return {"p": p}


@app.get("/required-alias-and-validation-alias/{p_val_alias}")
def read_required_alias_and_validation_alias(
    p: Annotated[str, Path(alias="p_alias", validation_alias="p_val_alias")],
):
    return {"p": p}


@pytest.mark.parametrize(