nano

commit 7c30d1fa699fd4acafb0e543b5b5d3ca783acaa5
parent 031166c34ddedd035780fd5b689b550e15d2cd01
Author: Benno Schulenberg <bensberg@telfort.nl>
Date:   Fri, 22 Feb 2019 14:09:17 +0100

display: account for zero-width characters when reserving space for '>'

That is: keep nibbling off characters until a character is eaten that
takes up at least one column.

This fixes https://savannah.gnu.org/bugs/?55759.
Reported-by: David Lawrence Ramsey <pooka109@gmail.com>

Bug existed since version 2.8.0, commit 5283acdc.

Diffstat:
M
src/winio.c
 | 
4
+++-

1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/src/winio.c b/src/winio.c
@@ -1990,7 +1990,9 @@ char *display_string(const char *buf, size_t column, size_t span, bool isdata)
 	/* If there is more text than can be shown, make room for the ">". */
 	if ((*buf != '\0' || column > beyond) &&
 					(currmenu != MMAIN || (isdata && !ISSET(SOFTWRAP)))) {
-		index = move_mbleft(converted, index);
+		do {
+			index = move_mbleft(converted, index);
+		} while (mbwidth(converted + index) == 0);
 
 #ifdef ENABLE_UTF8
 		/* Display the left half of a two-column character as '['. */