From 59149f02692804267e7cc0665d0334f6ff4675be Mon Sep 17 00:00:00 2001
From: zeertzjq <zeertzjq@outlook.com>
Date: Sat, 14 Sep 2024 10:40:29 +0200
Subject: [PATCH] patch 9.1.0730: Crash with cursor-screenline and narrow
 window

Problem:  Crash with cursor-screenline and narrow window
          (elig0n)
Solution: Don't set right_col when width2 is 0 (zeertzjq).

fixes: #15677
closes: #15678

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
---
 src/drawline.c                  |  2 +-
 src/testdir/test_cursorline.vim | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/drawline.c b/src/drawline.c
index b627192a4ee0f..fd5d56b43e508 100644
--- a/src/drawline.c
+++ b/src/drawline.c
@@ -62,7 +62,7 @@ margin_columns_win(win_T *wp, int *left_col, int *right_col)
     *left_col = 0;
     *right_col = width1;
 
-    if (wp->w_virtcol >= (colnr_T)width1)
+    if (wp->w_virtcol >= (colnr_T)width1 && width2 > 0)
 	*right_col = width1 + ((wp->w_virtcol - width1) / width2 + 1) * width2;
     if (wp->w_virtcol >= (colnr_T)width1 && width2 > 0)
 	*left_col = (wp->w_virtcol - width1) / width2 * width2 + width1;
diff --git a/src/testdir/test_cursorline.vim b/src/testdir/test_cursorline.vim
index bdde670d207a5..d258111ae4de1 100644
--- a/src/testdir/test_cursorline.vim
+++ b/src/testdir/test_cursorline.vim
@@ -309,6 +309,17 @@ func Test_cursorline_screenline_update()
   call StopVimInTerminal(buf)
 endfunc
 
+func Test_cursorline_screenline_zero_width()
+  CheckOption foldcolumn
+
+  set cursorline culopt=screenline winminwidth=1 foldcolumn=1
+  " This used to crash Vim
+  1vnew | redraw
+
+  bwipe!
+  set cursorline& culopt& winminwidth& foldcolumn&
+endfunc
+
 func Test_cursorline_cursorbind_horizontal_scroll()
   CheckScreendump
 

