From b5d7194d908795dd810b8e194c234a669eb13c94 Mon Sep 17 00:00:00 2001
From: bakkeby <bakkeby@gmail.com>
Date: Thu, 24 Feb 2022 13:27:04 +0100
Subject: [PATCH] Fix overtyping wide characters.
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Overtyping the first half of a wide character with the
second half of a wide character results in display garbage.
This is because the trailing dummy is not cleaned up.

i.e.  ATTR_WIDE, ATTR_WDUMMY, ATTR_WDUMMY

Here is a short script for demonstrating the behavior:

	#!/bin/sh
	alias printf=/usr/bin/printf
	printf こんにちは！; sleep 2
	printf '\x1b[5D'; sleep 2
	printf へ; sleep 2
	printf ' '; sleep 2
	echo

Ref.
   - https://git.suckless.org/st/commit/65f1dc428315ae9d7f362e10c668557c1379e7af.html
---
 st.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/st.c b/st.c
index 2df5c47..8d7e507 100644
--- a/st.c
+++ b/st.c
@@ -3180,6 +3180,10 @@ check_control_code:
 	if (width == 2) {
 		gp->mode |= ATTR_WIDE;
 		if (term.c.x+1 < term.col) {
+			if (gp[1].mode == ATTR_WIDE && term.c.x+2 < term.col) {
+				gp[2].u = ' ';
+				gp[2].mode &= ~ATTR_WDUMMY;
+			}
 			gp[1].u = '\0';
 			gp[1].mode = ATTR_WDUMMY;
 		}