Added support for GT and LT options in ZADD command

cmd_sorted_set.go

@@ -59,6 +59,8 @@ func (m *Miniredis) cmdZadd(c *server.Peer, cmd string, args []string) {
 	var (
 		nx    = false
 		xx    = false
+		gt    = false
+		lt    = false
 		ch    = false
 		incr  = false
 		elems = map[string]float64{}
@@ -75,6 +77,14 @@ outer:
 			xx = true
 			args = args[1:]
 			continue
+		case "GT":
+			gt = true
+			args = args[1:]
+			continue
+		case "LT":
+			lt = true
+			args = args[1:]
+			continue
 		case "CH":
 			ch = true
 			args = args[1:]
@@ -110,6 +120,14 @@ outer:
 		return
 	}
 
+	if gt && lt ||
+		gt && nx ||
+		lt && nx {
+		setDirty(c)
+		c.WriteError(msgGTLTandNX)
+		return
+	}
+
 	if incr && len(elems) > 1 {
 		setDirty(c)
 		c.WriteError(msgSingleElementPair)
@@ -149,6 +167,12 @@ outer:
 				continue
 			}
 			old := db.ssetScore(key, member)
+			if gt && score <= old {
+				continue
+			}
+			if lt && score >= old {
+				continue
+			}
 			if db.ssetAdd(key, score, member) {
 				res++
 			} else {

cmd_sorted_set_test.go

@@ -182,6 +182,14 @@ func TestSortedSetAdd(t *testing.T) {
 			"ZADD", "z", "NX", "1", "one", "2.2", "two", "3", "three",
 		)
 
+		must0(t, c,
+			"ZADD", "z", "GT", "1", "one",
+		)
+
+		must0(t, c,
+			"ZADD", "z", "GT", "2", "one",
+		)
+
 		must1(t, c,
 			"ZADD", "z", "NX", "1", "one", "4", "four",
 		)
@@ -271,6 +279,10 @@ func TestSortedSetAdd(t *testing.T) {
 			"ZADD", "set", "INCR", "1.0", "foo", "2.3", "bar",
 			proto.Error("ERR INCR option supports a single increment-element pair"),
 		)
+		mustDo(t, c,
+			"ZADD", "set", "GT", "LT", "1.0", "foo",
+			proto.Error(msgGTLTandNX),
+		)
 	})
 
 	useRESP3(t, c)

redis.go

@@ -35,6 +35,7 @@ const (
 	msgFPubsubUsage         = "ERR Unknown subcommand or wrong number of arguments for '%s'. Try PUBSUB HELP."
 	msgScriptFlush          = "ERR SCRIPT FLUSH only support SYNC|ASYNC option"
 	msgSingleElementPair    = "ERR INCR option supports a single increment-element pair"
+	msgGTLTandNX            = "ERR GT, LT and NX options are mutually exclusive"
 	msgInvalidStreamID      = "ERR Invalid stream ID specified as stream command argument"
 	msgStreamIDTooSmall     = "ERR The ID specified in XADD is equal or smaller than the target stream top item"
 	msgStreamIDZero         = "ERR The ID specified in XADD must be greater than 0-0"