From 7f5a2ec03f6188e1998e6f926b6e98efd2854c99 Mon Sep 17 00:00:00 2001
From: Evsyukov Denis <denis@evsyukov.org>
Date: Sat, 9 Sep 2023 21:24:48 +0300
Subject: [PATCH] fix: check version before changing

---
 gobrew.go | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/gobrew.go b/gobrew.go
index 1fd2c1d..83ae5fa 100644
--- a/gobrew.go
+++ b/gobrew.go
@@ -146,10 +146,12 @@ func (gb *GoBrew) ListVersions() {
 		version := versionSemantic.String()
 		// 1.8.0 -> 1.8, if version < 1.21.0
 		reMajorVersion := regexp.MustCompile("([0-9]+).([0-9]+).0")
-		vv, _ := strconv.Atoi(reMajorVersion.FindStringSubmatch(version)[2])
-		if vv < 21 {
-			if reMajorVersion.MatchString(version) {
-				version = strings.Split(version, ".")[0] + "." + strings.Split(version, ".")[1]
+		if len(reMajorVersion.FindStringSubmatch(version)) > 1 {
+			vv, _ := strconv.Atoi(reMajorVersion.FindStringSubmatch(version)[2])
+			if vv < 21 {
+				if reMajorVersion.MatchString(version) {
+					version = strings.Split(version, ".")[0] + "." + strings.Split(version, ".")[1]
+				}
 			}
 		}
 		if version == cv {