fix: prevent memory leak in _redlock_release of SimpleMemoryBackend (#807)

Author: moshego189

aiocache/backends/memory.py

@@ -93,8 +93,7 @@ async def _raw(self, command, *args, encoding="utf-8", _conn=None, **kwargs):
 
     async def _redlock_release(self, key, value):
         if self._cache.get(key) == value:
-            self._cache.pop(key)
-            return 1
+            return self.__delete(key)
         return 0
 
     def __delete(self, key):

tests/ut/backends/test_memory.py

@@ -173,9 +173,13 @@ async def test_raw(self, memory):
 
     async def test_redlock_release(self, memory):
         memory._cache.get.return_value = "lock"
+        fake = create_autospec(asyncio.TimerHandle, instance=True)
+        memory._handlers[Keys.KEY] = fake
         assert await memory._redlock_release(Keys.KEY, "lock") == 1
         memory._cache.get.assert_called_with(Keys.KEY)
-        memory._cache.pop.assert_called_with(Keys.KEY)
+        memory._cache.pop.assert_called_with(Keys.KEY, None)
+        assert fake.cancel.call_count == 1
+        assert Keys.KEY not in memory._handlers
 
     async def test_redlock_release_nokey(self, memory):
         memory._cache.get.return_value = None