diff --git a/fastapi/dependencies/utils.py b/fastapi/dependencies/utils.py index 2afc734ba..11ea6b926 100644 --- a/fastapi/dependencies/utils.py +++ b/fastapi/dependencies/utils.py @@ -204,7 +204,12 @@ def _get_signature(call: Callable[..., Any]) -> inspect.Signature: except NameError: # Handle type annotations with if TYPE_CHECKING, not used by FastAPI # e.g. dependency return types - signature = inspect.signature(call) + if sys.version_info >= (3, 14): + from annotationlib import Format + + signature = inspect.signature(call, annotation_format=Format.FORWARDREF) + else: + signature = inspect.signature(call) else: signature = inspect.signature(call) return signature diff --git a/tests/test_stringified_annotation_dependency_py314.py b/tests/test_stringified_annotation_dependency_py314.py new file mode 100644 index 000000000..da9b429fc --- /dev/null +++ b/tests/test_stringified_annotation_dependency_py314.py @@ -0,0 +1,30 @@ +from typing import TYPE_CHECKING, Annotated + +from fastapi import Depends, FastAPI +from fastapi.testclient import TestClient + +from .utils import needs_py314 + +if TYPE_CHECKING: # pragma: no cover + + class DummyUser: ... + + +@needs_py314 +def test_stringified_annotation(): + # python3.14: Use forward reference without "from __future__ import annotations" + async def get_current_user() -> DummyUser | None: + return None + + app = FastAPI() + + client = TestClient(app) + + @app.get("/") + async def get( + current_user: Annotated[DummyUser | None, Depends(get_current_user)], + ) -> str: + return "hello world" + + response = client.get("/") + assert response.status_code == 200 diff --git a/tests/utils.py b/tests/utils.py index efa0bfd52..4cbfee79f 100644 --- a/tests/utils.py +++ b/tests/utils.py @@ -6,8 +6,8 @@ needs_py39 = pytest.mark.skipif(sys.version_info < (3, 9), reason="requires pyth needs_py310 = pytest.mark.skipif( sys.version_info < (3, 10), reason="requires python3.10+" ) -needs_py_lt_314 = pytest.mark.skipif( - sys.version_info >= (3, 14), reason="requires python3.13-" +needs_py314 = pytest.mark.skipif( + sys.version_info < (3, 14), reason="requires python3.14+" )