fix(calendar): answer 400 when a CalDAV config body is not a JSON object (#6903)

tests/test_calendar_config_body.py

@@ -0,0 +1,35 @@
+"""The CalDAV config routes answer 400 for a body that is JSON but not an object."""
+import asyncio
+import json
+from types import SimpleNamespace
+
+import pytest
+from fastapi import HTTPException
+
+from routes.calendar_routes import _json_object_body
+
+
+def _request(raw: bytes):
+    async def _json():
+        return json.loads(raw)
+    return SimpleNamespace(json=_json)
+
+
+def _parse(raw: bytes):
+    return asyncio.run(_json_object_body(_request(raw)))
+
+
+def test_object_body_is_returned():
+    assert _parse(b'{"url": "https://dav.example/"}') == {"url": "https://dav.example/"}
+
+
+@pytest.mark.parametrize("raw", [b"", b"not json"])
+def test_unreadable_body_counts_as_empty(raw):
+    assert _parse(raw) == {}
+
+
+@pytest.mark.parametrize("raw", [b"[]", b'"x"', b"5", b"null"])
+def test_non_object_body_is_a_400(raw):
+    with pytest.raises(HTTPException) as exc:
+        _parse(raw)
+    assert exc.value.status_code == 400