Fix evaluating stringified annotations in Python 3.10 (also from __future__ import annotations)

fastapi/dependencies/utils.py

@@ -1,4 +1,5 @@
 import inspect
+import sys
 from contextlib import AsyncExitStack, contextmanager
 from copy import deepcopy
 from typing import (
@@ -205,7 +206,10 @@ def get_flat_params(dependant: Dependant) -> List[ModelField]:
 
 
 def get_typed_signature(call: Callable[..., Any]) -> inspect.Signature:
-    signature = inspect.signature(call)
+    if sys.version_info >= (3, 10):
+        signature = inspect.signature(call, eval_str=True)
+    else:
+        signature = inspect.signature(call)
     globalns = getattr(call, "__globals__", {})
     typed_params = [
         inspect.Parameter(
@@ -228,7 +232,10 @@ def get_typed_annotation(annotation: Any, globalns: Dict[str, Any]) -> Any:
 
 
 def get_typed_return_annotation(call: Callable[..., Any]) -> Any:
-    signature = inspect.signature(call)
+    if sys.version_info >= (3, 10):
+        signature = inspect.signature(call, eval_str=True)
+    else:
+        signature = inspect.signature(call)
     annotation = signature.return_annotation
 
     if annotation is inspect.Signature.empty:

tests/test_future/loging_tool.py

@@ -0,0 +1,10 @@
+from functools import wraps
+
+
+def login_required(func):
+    @wraps(func)
+    def wrapper(*args, **kwargs):
+        print("login")
+        return func(*args, **kwargs)
+
+    return wrapper

tests/test_future/test_future_6465.py

@@ -0,0 +1,34 @@
+from __future__ import annotations
+
+import sys
+
+from ..utils import needs_py310
+
+if sys.version_info > (3, 10):
+    from typing import Optional
+
+    from fastapi import FastAPI
+    from fastapi.testclient import TestClient
+    from pydantic import BaseModel
+
+    from .loging_tool import login_required
+
+    app = FastAPI()
+    client = TestClient(app)
+
+    class Item(BaseModel):
+        name: str
+        description: Optional[str] = None
+        price: float
+        tax: Optional[float] = None
+
+    @app.get("/items/")
+    @login_required
+    def get_item(id: int) -> Item:
+        return Item(name="name", price=42.42)
+
+
+@needs_py310
+def test_future_6465():
+    res = client.get("/items?id=3")
+    assert res.status_code == 200

tests/test_future/test_future_9095.py

@@ -0,0 +1,28 @@
+from __future__ import annotations
+
+import sys
+
+from ..utils import needs_py310
+
+if sys.version_info > (3, 10):
+    from fastapi import Depends, FastAPI
+    from fastapi.testclient import TestClient
+    from starlette.requests import Request
+
+    app = FastAPI()
+
+    client = TestClient(app)
+
+    class Test:
+        def __call__(self, request: Request):
+            return "test"
+
+    @app.get("/test/")
+    def call(test: str = Depends(Test())):
+        return {"test": test}
+
+
+@needs_py310
+def test_call():
+    response = client.get("/test")
+    assert response.status_code == 200