Fix Limit argument and add CountOnly argument

Author: ofekshenawa

search_commands.go

@@ -320,6 +320,7 @@ type FTSearchOptions struct {
 	SortByWithCount bool
 	LimitOffset     int
 	Limit           int
+	CountOnly       bool
 	Params          map[string]interface{}
 	DialectVersion  int
 }
@@ -1954,8 +1955,12 @@ func (c cmdable) FTSearchWithArgs(ctx context.Context, index string, query strin
 				args = append(args, "WITHCOUNT")
 			}
 		}
-		if options.LimitOffset >= 0 && options.Limit > 0 {
-			args = append(args, "LIMIT", options.LimitOffset, options.Limit)
+		if options.CountOnly {
+			args = append(args, "LIMIT", 0, 0)
+		} else {
+			if options.LimitOffset >= 0 && options.Limit > 0 || options.LimitOffset > 0 && options.Limit == 0 {
+				args = append(args, "LIMIT", options.LimitOffset, options.Limit)
+			}
 		}
 		if options.Params != nil {
 			args = append(args, "PARAMS", len(options.Params)*2)