from fastapi._compat import v2

    # For coverage
    field_info = FieldInfo(annotation=str)
    field = v2.ModelField(name="foo", field_info=field_info)
    assert field.default is Undefined


def test_complex():
    app = FastAPI()

    @app.post("/")
    def foo(foo: Union[str, list[int]]):
        return foo

    client = TestClient(app)

    response = client.post("/", json="bar")