Fix bug in `StateFilter.return_expanded()` and add some tests. (#12016)

1 files changed, 109 insertions, 0 deletions

diff --git a/tests/storage/test_state.py b/tests/storage/test_state.py
index 70d52b088c..28c767ecfd 100644
--- a/tests/storage/test_state.py
+++ b/tests/storage/test_state.py
@@ -992,3 +992,112 @@ class StateFilterDifferenceTestCase(TestCase):
             StateFilter.none(),
             StateFilter.all(),
         )
+
+
+class StateFilterTestCase(TestCase):
+    def test_return_expanded(self):
+        """
+        Tests the behaviour of the return_expanded() function that expands
+        StateFilters to include more state types (for the sake of cache hit rate).
+        """
+
+        self.assertEqual(StateFilter.all().return_expanded(), StateFilter.all())
+
+        self.assertEqual(StateFilter.none().return_expanded(), StateFilter.none())
+
+        # Concrete-only state filters stay the same
+        # (Case: mixed filter)
+        self.assertEqual(
+            StateFilter.freeze(
+                {
+                    EventTypes.Member: {"@wombat:test", "@alicia:test"},
+                    "some.other.state.type": {""},
+                },
+                include_others=False,
+            ).return_expanded(),
+            StateFilter.freeze(
+                {
+                    EventTypes.Member: {"@wombat:test", "@alicia:test"},
+                    "some.other.state.type": {""},
+                },
+                include_others=False,
+            ),
+        )
+
+        # Concrete-only state filters stay the same
+        # (Case: non-member-only filter)
+        self.assertEqual(
+            StateFilter.freeze(
+                {"some.other.state.type": {""}}, include_others=False
+            ).return_expanded(),
+            StateFilter.freeze({"some.other.state.type": {""}}, include_others=False),
+        )
+
+        # Concrete-only state filters stay the same
+        # (Case: member-only filter)
+        self.assertEqual(
+            StateFilter.freeze(
+                {
+                    EventTypes.Member: {"@wombat:test", "@alicia:test"},
+                },
+                include_others=False,
+            ).return_expanded(),
+            StateFilter.freeze(
+                {
+                    EventTypes.Member: {"@wombat:test", "@alicia:test"},
+                },
+                include_others=False,
+            ),
+        )
+
+        # Wildcard member-only state filters stay the same
+        self.assertEqual(
+            StateFilter.freeze(
+                {EventTypes.Member: None},
+                include_others=False,
+            ).return_expanded(),
+            StateFilter.freeze(
+                {EventTypes.Member: None},
+                include_others=False,
+            ),
+        )
+
+        # If there is a wildcard in the non-member portion of the filter,
+        # it's expanded to include ALL non-member events.
+        # (Case: mixed filter)
+        self.assertEqual(
+            StateFilter.freeze(
+                {
+                    EventTypes.Member: {"@wombat:test", "@alicia:test"},
+                    "some.other.state.type": None,
+                },
+                include_others=False,
+            ).return_expanded(),
+            StateFilter.freeze(
+                {EventTypes.Member: {"@wombat:test", "@alicia:test"}},
+                include_others=True,
+            ),
+        )
+
+        # If there is a wildcard in the non-member portion of the filter,
+        # it's expanded to include ALL non-member events.
+        # (Case: non-member-only filter)
+        self.assertEqual(
+            StateFilter.freeze(
+                {
+                    "some.other.state.type": None,
+                },
+                include_others=False,
+            ).return_expanded(),
+            StateFilter.freeze({EventTypes.Member: set()}, include_others=True),
+        )
+        self.assertEqual(
+            StateFilter.freeze(
+                {
+                    "some.other.state.type": None,
+                    "yet.another.state.type": {"wombat"},
+                },
+                include_others=False,
+            ).return_expanded(),
+            StateFilter.freeze({EventTypes.Member: set()}, include_others=True),
+        )