From ce2200e9080d84a0e658fd1523f4fac619b58da4 Mon Sep 17 00:00:00 2001
From: Junegunn Choi <junegunn.c@gmail.com>
Date: Tue, 30 Sep 2025 17:44:29 +0900
Subject: [PATCH] Do not allow gutter characters with width other than 1

---
 src/options.go | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/src/options.go b/src/options.go
index 7ed6c77d..d3be6821 100644
--- a/src/options.go
+++ b/src/options.go
@@ -3412,16 +3412,9 @@ func validateOptions(opts *Options) error {
 		}
 	}
 
-	if opts.Gutter != nil {
-		if err := validateSign(*opts.Gutter, "gutter", 1); err != nil {
-			return err
-		}
-	}
-
-	if opts.GutterRaw != nil {
-		if err := validateSign(*opts.GutterRaw, "gutter", 1); err != nil {
-			return err
-		}
+	if opts.Gutter != nil && uniseg.StringWidth(*opts.Gutter) != 1 ||
+		opts.GutterRaw != nil && uniseg.StringWidth(*opts.GutterRaw) != 1 {
+		return errors.New("gutter display width should be 1")
 	}
 
 	if opts.Scrollbar != nil {