add unit test

Author: alessandro-nori

tests/catalog/test_rest.py

@@ -554,6 +554,23 @@ def test_list_namespace_with_parent_200(rest_mock: Mocker) -> None:
         ("accounting", "tax"),
     ]
 
+def test_list_namespace_with_parent_404(rest_mock: Mocker) -> None:
+    rest_mock.get(
+        f"{TEST_URI}v1/namespaces?parent=some_namespace",
+        json={
+            "error": {
+                "message": "Namespace provided in the `parent` query parameter is not found",
+                "type": "NoSuchNamespaceException",
+                "code": 404,
+            }
+        },
+        status_code=404,
+        request_headers=TEST_HEADERS,
+    )
+
+    with pytest.raises(NoSuchNamespaceError):
+        RestCatalog("rest", uri=TEST_URI, token=TEST_TOKEN).list_namespaces(("some_namespace",))
+
 
 @pytest.mark.filterwarnings(
     "ignore:Deprecated in 0.8.0, will be removed in 1.0.0. Iceberg REST client is missing the OAuth2 server URI:DeprecationWarning"