✅ Add tests for dependency with yield catching exceptions and re-raising

tests/test_dependency_after_yield_raise.py

@@ -0,0 +1,63 @@
+from typing import Annotated, Any
+
+import pytest
+from fastapi import Depends, FastAPI, HTTPException
+from fastapi.testclient import TestClient
+
+
+class CustomError(Exception):
+    pass
+
+
+def catching_dep() -> Any:
+    try:
+        yield "s"
+    except CustomError as err:
+        raise HTTPException(status_code=418, detail="Session error") from err
+
+
+def broken_dep() -> Any:
+    yield "s"
+    raise ValueError("Broken after yield")
+
+
+app = FastAPI()
+
+
+@app.get("/catching")
+def catching(d: Annotated[str, Depends(catching_dep)]) -> Any:
+    raise CustomError("Simulated error during streaming")
+
+
+@app.get("/broken")
+def broken(d: Annotated[str, Depends(broken_dep)]) -> Any:
+    return {"message": "all good?"}
+
+
+client = TestClient(app)
+
+
+def test_catching():
+    response = client.get("/catching")
+    assert response.status_code == 418
+    assert response.json() == {"detail": "Session error"}
+
+
+def test_broken_catch():
+    """
+    When a dependency with yield raises after the yield (not in an except), the
+    response is already "successfully" sent back to the client, but there's still
+    an error in the server afterwards, an exception is raised and captured or shown
+    in the server logs.
+    """
+    with pytest.raises(ValueError, match="Broken after yield"):
+        response = client.get("/broken")
+        assert response.status_code == 200
+        assert response.json() == {"message": "all good?"}
+
+
+def test_broken_return_finishes():
+    client = TestClient(app, raise_server_exceptions=False)
+    response = client.get("/broken")
+    assert response.status_code == 200
+    assert response.json() == {"message": "all good?"}