vim-patch:9.1.0729: Wrong cursor-screenline when resizing window

Problem:  Wrong cursor-screenline when resizing window
Solution: Invalidate saved left_col and right_col when width1 or width2
          change.

closes: vim/vim#15679

https://github.com/vim/vim/commit/86dc4f8b432233a01d022c3e71df53db58229713

1 files changed, 7 insertions, 8 deletions

diff --git a/src/nvim/drawline.c b/src/nvim/drawline.c
index b5273a54ca..c85b9d2288 100644
--- a/src/nvim/drawline.c
+++ b/src/nvim/drawline.c
@@ -170,24 +170,22 @@ static void margin_columns_win(win_T *wp, int *left_col, int *right_col)
   // cache previous calculations depending on w_virtcol
   static int saved_w_virtcol;
   static win_T *prev_wp;
+  static int prev_width1;
+  static int prev_width2;
   static int prev_left_col;
   static int prev_right_col;
-  static int prev_col_off;
 
   int cur_col_off = win_col_off(wp);
-  int width1;
-  int width2;
+  int width1 = wp->w_width_inner - cur_col_off;
+  int width2 = width1 + win_col_off2(wp);
 
   if (saved_w_virtcol == wp->w_virtcol && prev_wp == wp
-      && prev_col_off == cur_col_off) {
+      && prev_width1 == width1 && prev_width2 == width2) {
     *right_col = prev_right_col;
     *left_col = prev_left_col;
     return;
   }
 
-  width1 = wp->w_width_inner - cur_col_off;
-  width2 = width1 + win_col_off2(wp);
-
   *left_col = 0;
   *right_col = width1;
 
@@ -202,8 +200,9 @@ static void margin_columns_win(win_T *wp, int *left_col, int *right_col)
   prev_left_col = *left_col;
   prev_right_col = *right_col;
   prev_wp = wp;
+  prev_width1 = width1;
+  prev_width2 = width2;
   saved_w_virtcol = wp->w_virtcol;
-  prev_col_off = cur_col_off;
 }
 
 /// Put a single char from an UTF-8 buffer into a line buffer.