diff --git a/fastapi/dependencies/utils.py b/fastapi/dependencies/utils.py index 02284b4ed001b..4f984177a4085 100644 --- a/fastapi/dependencies/utils.py +++ b/fastapi/dependencies/utils.py @@ -1,6 +1,6 @@ import inspect from contextlib import AsyncExitStack, contextmanager -from copy import deepcopy +from copy import copy, deepcopy from typing import ( Any, Callable, @@ -384,6 +384,8 @@ def analyze_param( field_info.annotation = type_annotation if depends is not None and depends.dependency is None: + # Copy `depends` before mutating it + depends = copy(depends) depends.dependency = type_annotation if lenient_issubclass( diff --git a/tests/test_generic_parameterless_depends.py b/tests/test_generic_parameterless_depends.py new file mode 100644 index 0000000000000..fe13ff89b80ef --- /dev/null +++ b/tests/test_generic_parameterless_depends.py @@ -0,0 +1,77 @@ +from typing import TypeVar + +from fastapi import Depends, FastAPI +from fastapi.testclient import TestClient +from typing_extensions import Annotated + +app = FastAPI() + +T = TypeVar("T") + +Dep = Annotated[T, Depends()] + + +class A: + pass + + +class B: + pass + + +@app.get("/a") +async def a(dep: Dep[A]): + return {"cls": dep.__class__.__name__} + + +@app.get("/b") +async def b(dep: Dep[B]): + return {"cls": dep.__class__.__name__} + + +client = TestClient(app) + + +def test_generic_parameterless_depends(): + response = client.get("/a") + assert response.status_code == 200, response.text + assert response.json() == {"cls": "A"} + + response = client.get("/b") + assert response.status_code == 200, response.text + assert response.json() == {"cls": "B"} + + +def test_openapi_schema(): + response = client.get("/openapi.json") + assert response.status_code == 200, response.text + assert response.json() == { + "info": {"title": "FastAPI", "version": "0.1.0"}, + "openapi": "3.1.0", + "paths": { + "/a": { + "get": { + "operationId": "a_a_get", + "responses": { + "200": { + "content": {"application/json": {"schema": {}}}, + "description": "Successful " "Response", + } + }, + "summary": "A", + } + }, + "/b": { + "get": { + "operationId": "b_b_get", + "responses": { + "200": { + "content": {"application/json": {"schema": {}}}, + "description": "Successful " "Response", + } + }, + "summary": "B", + } + }, + }, + }