diff --git a/test/emqttd_mqueue_tests.erl b/test/emqttd_mqueue_tests.erl
index bbb9e7daa..6d20b3cbf 100644
--- a/test/emqttd_mqueue_tests.erl
+++ b/test/emqttd_mqueue_tests.erl
@@ -70,7 +70,9 @@ simple_mqueue_test() ->
             {high_watermark, 0.6},
             {queue_qos0, false}],
     Q = ?Q:new("simple_queue", Opts, alarm_fun()),
-
+    ?assertEqual(simple, ?Q:type(Q)),
+    ?assertEqual(3, ?Q:max_len(Q)),
+    ?assertEqual(<<"simple_queue">>, ?Q:name(Q)),
     ?assert(?Q:is_empty(Q)),
     Q1 = ?Q:in(#mqtt_message{qos = 1, payload = <<"1">>}, Q),
     Q2 = ?Q:in(#mqtt_message{qos = 1, payload = <<"2">>}, Q1),
@@ -78,7 +80,25 @@ simple_mqueue_test() ->
     Q4 = ?Q:in(#mqtt_message{qos = 1, payload = <<"4">>}, Q3),
     ?assertEqual(3, ?Q:len(Q4)),
     {{value, Msg}, Q5} = ?Q:out(Q4),
-    ?assertMatch(<<"2">>, Msg#mqtt_message.payload).
+    ?assertMatch(<<"2">>, Msg#mqtt_message.payload),
+    ?assertEqual([{len, 2}, {max_len, 3}, {dropped, 1}], ?Q:stats(Q5)).
+
+infinity_simple_mqueue_test() ->
+    Opts = [{type, simple},
+            {max_length, infinity},
+            {low_watermark, 0.2},
+            {high_watermark, 0.6},
+            {queue_qos0, false}],
+    Q = ?Q:new("infinity_simple_queue", Opts, alarm_fun()),
+    ?assert(?Q:is_empty(Q)),
+    ?assertEqual(infinity, ?Q:max_len(Q)),
+    Qx = lists:foldl(fun(I, AccQ) ->
+                    ?Q:in(#mqtt_message{qos = 1, payload = iolist_to_binary([I])}, AccQ)
+            end, Q, lists:seq(1, 255)),
+    ?assertEqual(255, ?Q:len(Qx)),
+    ?assertEqual([{len, 255}, {max_len, infinity}, {dropped, 0}], ?Q:stats(Qx)),
+    {{value, V}, Qy} = ?Q:out(Qx),
+    ?assertEqual(<<1>>, V#mqtt_message.payload).
 
 priority_mqueue_test() ->
     Opts = [{type, priority},
@@ -88,6 +108,9 @@ priority_mqueue_test() ->
             {high_watermark, 0.6},
             {queue_qos0, false}],
     Q = ?Q:new("priority_queue", Opts, alarm_fun()),
+    ?assertEqual(priority, ?Q:type(Q)),
+    ?assertEqual(3, ?Q:max_len(Q)),
+    ?assertEqual(<<"priority_queue">>, ?Q:name(Q)),
 
     ?assert(?Q:is_empty(Q)),
     Q1 = ?Q:in(#mqtt_message{qos = 1, topic = <<"t1">>}, Q),
@@ -102,6 +125,21 @@ priority_mqueue_test() ->
     ?assertEqual(5, ?Q:len(Q6)),
     {{value, Msg}, Q7} = ?Q:out(Q6),
     ?assertMatch(<<"t">>, Msg#mqtt_message.topic).
+
+infinity_priority_mqueue_test() ->
+    Opts = [{type, priority},
+            {priority, [{<<"t1">>, 10}, {<<"t2">>, 8}]},
+            {max_length, infinity},
+            {queue_qos0, false}],
+    Q = ?Q:new("infinity_priority_queue", Opts, alarm_fun()),
+    ?assertEqual(infinity, ?Q:max_len(Q)),
+    Qx = lists:foldl(fun(I, AccQ) ->
+                    AccQ1 =
+                    ?Q:in(#mqtt_message{topic = <<"t1">>, qos = 1, payload = iolist_to_binary([I])}, AccQ),
+                    ?Q:in(#mqtt_message{topic = <<"t">>, qos = 1, payload = iolist_to_binary([I])}, AccQ1)
+            end, Q, lists:seq(1, 255)),
+    ?assertEqual(510, ?Q:len(Qx)),
+    ?assertEqual([{len, 510}, {max_len, infinity}, {dropped, 0}], ?Q:stats(Qx)).
  
 alarm_fun() -> fun(_, _) -> alarm_fun() end.