diff --git a/command.go b/command.go
index 7f49b78..b202de9 100644
--- a/command.go
+++ b/command.go
@@ -1395,10 +1395,10 @@ func (cmd *XPendingExtCmd) readReply(rd *proto.Reader) error {
 
 type XInfoGroupsCmd struct {
 	baseCmd
-	val []XInfoGroups
+	val []XInfoGroup
 }
 
-type XInfoGroups struct {
+type XInfoGroup struct {
 	Name            string
 	Consumers       int64
 	Pending         int64
@@ -1416,11 +1416,11 @@ func NewXInfoGroupsCmd(ctx context.Context, stream string) *XInfoGroupsCmd {
 	}
 }
 
-func (cmd *XInfoGroupsCmd) Val() []XInfoGroups {
+func (cmd *XInfoGroupsCmd) Val() []XInfoGroup {
 	return cmd.val
 }
 
-func (cmd *XInfoGroupsCmd) Result() ([]XInfoGroups, error) {
+func (cmd *XInfoGroupsCmd) Result() ([]XInfoGroup, error) {
 	return cmd.val, cmd.err
 }
 
@@ -1429,58 +1429,66 @@ func (cmd *XInfoGroupsCmd) String() string {
 }
 
 func (cmd *XInfoGroupsCmd) readReply(rd *proto.Reader) error {
-	_, err := rd.ReadArrayReply(func(rd *proto.Reader, n int64) (interface{}, error) {
-		for i := int64(0); i < n; i++ {
-			v, err := rd.ReadReply(xGroupInfoParser)
-			if err != nil {
-				return nil, err
-			}
-			cmd.val = append(cmd.val, v.(XInfoGroups))
+	n, err := rd.ReadArrayLen()
+	if err != nil {
+		return err
+	}
+
+	cmd.val = make([]XInfoGroup, n)
+
+	for i := 0; i < n; i++ {
+		cmd.val[i], err = readXGroupInfo(rd)
+		if err != nil {
+			return err
 		}
-		return nil, nil
-	})
-	return err
+	}
+
+	return nil
 }
 
-func xGroupInfoParser(rd *proto.Reader, n int64) (interface{}, error) {
-	if n != 8 {
-		return nil, fmt.Errorf("redis: got %d elements in XINFO GROUPS reply,"+
-			"wanted 8", n)
+func readXGroupInfo(rd *proto.Reader) (XInfoGroup, error) {
+	var group XInfoGroup
+
+	n, err := rd.ReadArrayLen()
+	if err != nil {
+		return group, err
+	}
+	if n != 8 {
+		return group, fmt.Errorf("redis: got %d elements in XINFO GROUPS reply, wanted 8", n)
 	}
-	var (
-		err error
-		grp XInfoGroups
-		key string
-		val string
-	)
 
 	for i := 0; i < 4; i++ {
-		key, err = rd.ReadString()
+		key, err := rd.ReadString()
 		if err != nil {
-			return nil, err
+			return group, err
 		}
-		val, err = rd.ReadString()
+
+		val, err := rd.ReadString()
 		if err != nil {
-			return nil, err
+			return group, err
 		}
+
 		switch key {
 		case "name":
-			grp.Name = val
+			group.Name = val
 		case "consumers":
-			grp.Consumers, err = strconv.ParseInt(val, 0, 64)
+			group.Consumers, err = strconv.ParseInt(val, 0, 64)
+			if err != nil {
+				return group, err
+			}
 		case "pending":
-			grp.Pending, err = strconv.ParseInt(val, 0, 64)
+			group.Pending, err = strconv.ParseInt(val, 0, 64)
+			if err != nil {
+				return group, err
+			}
 		case "last-delivered-id":
-			grp.LastDeliveredID = val
+			group.LastDeliveredID = val
 		default:
-			return nil, fmt.Errorf("redis: unexpected content %s "+
-				"in XINFO GROUPS reply", key)
-		}
-		if err != nil {
-			return nil, err
+			return group, fmt.Errorf("redis: unexpected content %s in XINFO GROUPS reply", key)
 		}
 	}
-	return grp, err
+
+	return group, nil
 }
 
 //------------------------------------------------------------------------------
@@ -2257,7 +2265,7 @@ func (cmd *SlowLogCmd) readReply(rd *proto.Reader) error {
 			}
 
 			cmdString := make([]string, cmdLen)
-			for i := 0; i < int(cmdLen); i++ {
+			for i := 0; i < cmdLen; i++ {
 				cmdString[i], err = rd.ReadString()
 				if err != nil {
 					return nil, err
@@ -2265,7 +2273,7 @@ func (cmd *SlowLogCmd) readReply(rd *proto.Reader) error {
 			}
 
 			var address, name string
-			for i := 4; i < int(n); i++ {
+			for i := 4; i < n; i++ {
 				str, err := rd.ReadString()
 				if err != nil {
 					return nil, err
diff --git a/commands.go b/commands.go
index a6c9eee..973aaf5 100644
--- a/commands.go
+++ b/commands.go
@@ -1517,7 +1517,7 @@ func (c cmdable) XRead(ctx context.Context, a *XReadArgs) *XStreamSliceCmd {
 		keyPos += 2
 	}
 	args = append(args, "streams")
-	keyPos += 1
+	keyPos++
 	for _, s := range a.Streams {
 		args = append(args, s)
 	}
@@ -1592,10 +1592,10 @@ func (c cmdable) XReadGroup(ctx context.Context, a *XReadGroupArgs) *XStreamSlic
 	}
 	if a.NoAck {
 		args = append(args, "noack")
-		keyPos += 1
+		keyPos++
 	}
 	args = append(args, "streams")
-	keyPos += 1
+	keyPos++
 	for _, s := range a.Streams {
 		args = append(args, s)
 	}
diff --git a/internal/proto/reader.go b/internal/proto/reader.go
index 4a16349..d9e6c12 100644
--- a/internal/proto/reader.go
+++ b/internal/proto/reader.go
@@ -181,7 +181,7 @@ func (r *Reader) ReadArrayReply(m MultiBulkParse) (interface{}, error) {
 	}
 }
 
-func (r *Reader) ReadArrayLen() (int64, error) {
+func (r *Reader) ReadArrayLen() (int, error) {
 	line, err := r.ReadLine()
 	if err != nil {
 		return 0, err
@@ -190,7 +190,11 @@ func (r *Reader) ReadArrayLen() (int64, error) {
 	case ErrorReply:
 		return 0, ParseErrorReply(line)
 	case ArrayReply:
-		return parseArrayLen(line)
+		n, err := parseArrayLen(line)
+		if err != nil {
+			return 0, err
+		}
+		return int(n), nil
 	default:
 		return 0, fmt.Errorf("redis: can't parse array reply: %.100q", line)
 	}
@@ -216,7 +220,8 @@ func (r *Reader) ReadScanReply() ([]string, uint64, error) {
 	}
 
 	keys := make([]string, n)
-	for i := int64(0); i < n; i++ {
+
+	for i := 0; i < n; i++ {
 		key, err := r.ReadString()
 		if err != nil {
 			return nil, 0, err