Fix truncation of long branch names containing non-ASCII characters

Author: stefanhaller

pkg/gui/presentation/branches.go

@@ -79,10 +79,10 @@ func getBranchDisplayStrings(
 	}
 
 	// Don't bother shortening branch names that are already 3 characters or less
-	if len(displayName) > max(availableWidth, 3) {
+	if runewidth.StringWidth(displayName) > max(availableWidth, 3) {
 		// Never shorten the branch name to less then 3 characters
 		len := max(availableWidth, 4)
-		displayName = displayName[:len-1] + "…"
+		displayName = runewidth.Truncate(displayName, len, "…")
 	}
 	coloredName := nameTextStyle.Sprint(displayName)
 	if checkedOutByWorkTree {

pkg/gui/presentation/branches_test.go

@@ -51,7 +51,7 @@ func Test_getBranchDisplayStrings(t *testing.T) {
 			useIcons:             false,
 			checkedOutByWorktree: false,
 			showDivergenceCfg:    "none",
-			expected:             []string{"1m", "🍉_special_c…"}, // truncated, but shouldn't
+			expected:             []string{"1m", "🍉_special_char"},
 		},
 		{
 			branch:               &models.Branch{Name: "branch_name", Recency: "1m"},
@@ -202,7 +202,7 @@ func Test_getBranchDisplayStrings(t *testing.T) {
 			useIcons:             false,
 			checkedOutByWorktree: false,
 			showDivergenceCfg:    "none",
-			expected:             []string{"1m", "🍉_special_…"}, // truncated two runes too much
+			expected:             []string{"1m", "🍉_special_ch…"},
 		},
 		{
 			branch:               &models.Branch{Name: "branch_name", Recency: "1m"},