More robust parsing of memory stats response (#3247)

Make the parsing of memory stats response more robust, to not break on
changes that will be added to the Redis server.

Also make a test related to client kill by maxage more resilient.

Co-authored-by: Gabriel Erzse <gabriel.erzse@redis.com>

Author: gerzse

redis/_parsers/helpers.py

@@ -80,7 +80,7 @@ def parse_memory_stats(response, **kwargs):
     """Parse the results of MEMORY STATS"""
     stats = pairs_to_dict(response, decode_keys=True, decode_string_values=True)
     for key, value in stats.items():
-        if key.startswith("db."):
+        if key.startswith("db.") and isinstance(value, list):
             stats[key] = pairs_to_dict(
                 value, decode_keys=True, decode_string_values=True
             )

tests/test_asyncio/test_commands.py

@@ -3235,7 +3235,7 @@ async def test_memory_stats(self, r: redis.Redis):
         assert isinstance(stats, dict)
         for key, value in stats.items():
             if key.startswith("db."):
-                assert isinstance(value, dict)
+                assert not isinstance(value, list)
 
     @skip_if_server_version_lt("4.0.0")
     async def test_memory_usage(self, r: redis.Redis):

tests/test_commands.py

@@ -712,7 +712,7 @@ def test_client_kill_filter_by_user(self, r, request):
     def test_client_kill_filter_by_maxage(self, r, request):
         _get_client(redis.Redis, request, flushdb=False)
         time.sleep(4)
-        assert len(r.client_list()) == 2
+        assert len(r.client_list()) >= 2
         r.client_kill_filter(maxage=2)
         assert len(r.client_list()) == 1
 
@@ -4914,7 +4914,7 @@ def test_memory_stats(self, r):
         assert isinstance(stats, dict)
         for key, value in stats.items():
             if key.startswith("db."):
-                assert isinstance(value, dict)
+                assert not isinstance(value, list)
 
     @skip_if_server_version_lt("4.0.0")
     def test_memory_usage(self, r):