diff --git a/inc/Maat_rule.h b/inc/Maat_rule.h
index b7e21a9..d9f1d49 100644
--- a/inc/Maat_rule.h
+++ b/inc/Maat_rule.h
@@ -175,7 +175,7 @@ enum MAAT_SCAN_OPT
 int Maat_set_scan_status(Maat_feather_t feather,scan_status_t* mid,enum MAAT_SCAN_OPT type,const void* value,int size);
 
 //Return hit rule number, return -1 when error occurs,return -2 when hit current region
-//mid MUST set NULL before fist call
+//mid MUST set to NULL before fist call
 int Maat_scan_intval(Maat_feather_t feather,int table_id
 						,unsigned int intval
 						,struct Maat_rule_t*result,int rule_num
diff --git a/src/entry/Maat_command.cpp b/src/entry/Maat_command.cpp
index 5dd7cec..f22edfc 100644
--- a/src/entry/Maat_command.cpp
+++ b/src/entry/Maat_command.cpp
@@ -419,6 +419,7 @@ int get_rm_key_list(unsigned int version,redisContext *c,struct serial_rule_t**
 	assert(reply->type==REDIS_REPLY_ARRAY);
 	if(reply->elements==0)
 	{
+		//a duplicate rule_id would induce this error.
 		MESA_handle_runtime_log(logger, RLOG_LV_FATAL, maat_redis_monitor,"Got nothing after ZRANGEBYSCORE %s (%d %d",rm_status_sset,version,version_in_redis);
 		freeReplyObject(reply);
 		return -1;
@@ -616,7 +617,7 @@ int calculate_serial_rule_num(struct _Maat_cmd_inner_t* _cmd,int * new_region_cn
 			*new_region_cnt+=cmd->groups[i].region_num;
 			(*new_group_cnt)++;		
 		}
-		//for MAAT_OP_DEL, if the group's refcnt>0, group->region_num=0.
+		//for MAAT_OP_DEL, if the group's refcnt>1, group->region_num=0.
 		//so it's OK to add.
 		serial_num+=cmd->groups[i].region_num;
 	}
diff --git a/test/Makefile b/test/Makefile
index 9c83e95..f020103 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -1,8 +1,6 @@
-LIBS= ../lib/libmaatframe.so -lhiredis_vip
-INC=-I../inc/ -I ../src/entry/ -I../src/inc_internal/ -I/usr/include/MESA/
+LIBS=../lib/libmaatframe.so
+INC=-I../inc/ -I/usr/include/MESA/
 all:
-	g++ -o maat_redis_tool.o -c -g -Wall maat_redis_tool.cpp $(INC)
-	g++ -o maat_redis_tool maat_redis_tool.o $(LIBS)
-	g++ -o digest_gen -g digest_gen.c $(INC) $(LIBS)
+	g++ -o maat_test -g -Wall maat_test.cpp $(INC) $(LIBS) -lMESA_handle_logger
 clean:
-	rm *.o
+	rm maat_test test.log* -f