From 430bd238706fefd03206b1b2b72e90e47ffc4ea2 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Fri, 7 Oct 2022 11:35:38 +0530
Subject: [PATCH] Fix decoding of letter trailer CSI key event

---
 tools/tui/loop/key-encoding.go | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/tui/loop/key-encoding.go b/tools/tui/loop/key-encoding.go
index 5c1fbe745..d9a854005 100644
--- a/tools/tui/loop/key-encoding.go
+++ b/tools/tui/loop/key-encoding.go
@@ -154,9 +154,14 @@ func KeyEventFromCSI(csi string) *KeyEvent {
 		third_section = get_sub_sections(sections[2])
 	}
 	var ans = KeyEvent{Type: PRESS}
-	keynum := first_section[0]
+	var keynum int
 	if val, ok := letter_trailer_to_csi_number_map[last_char]; ok {
 		keynum = val
+	} else {
+		if len(first_section) == 0 {
+			return nil
+		}
+		keynum = first_section[0]
 	}
 
 	key_name := func(keynum int) string {