From 9c0c31dfaab3dd3b3debb2604fec580ca6fdfb62 Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Tue, 31 May 2022 09:35:49 -0600
Subject: [PATCH] [buffer] When deleting glyphs, check cluster backwards as
 well

---
 src/hb-buffer.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/hb-buffer.cc b/src/hb-buffer.cc
index 1baa9af5c..bd786f9f4 100644
--- a/src/hb-buffer.cc
+++ b/src/hb-buffer.cc
@@ -543,7 +543,8 @@ hb_buffer_t::delete_glyph ()
   /* The logic here is duplicated in hb_ot_hide_default_ignorables(). */
 
   unsigned int cluster = info[idx].cluster;
-  if (idx + 1 < len && cluster == info[idx + 1].cluster)
+  if ((idx + 1 < len && cluster == info[idx + 1].cluster) ||
+      (out_len && cluster == out_info[out_len - 1].cluster))
   {
     /* Cluster survives; do nothing. */
     goto done;