vim-patch:9.0.0707: with 'smoothscroll' cursor position not adjusted in long line

Problem:    With 'smoothscroll' and 'scrolloff' non-zero the cursor position
            is not properly adjusted in a long line.
Solution:   Move the cursor further up or down in the line.

https://github.com/vim/vim/commit/118c235112854f34182d968613d7fe98be3b290b

Co-authored-by: Bram Moolenaar <Bram@vim.org>

1 files changed, 19 insertions, 10 deletions

diff --git a/src/nvim/move.c b/src/nvim/move.c
index 144384c294..e7f5959dbb 100644
--- a/src/nvim/move.c
+++ b/src/nvim/move.c
@@ -1210,20 +1210,24 @@ bool scrolldown(long line_count, int byfold)
   }
 
   if (curwin->w_cursor.lnum == curwin->w_topline && do_sms) {
+    long so = curwin->w_p_so >= 0 ? curwin->w_p_so : p_so;
+    long scrolloff_cols = so == 0 ? 0 : width1 + (so - 1) * width2;
+
     // make sure the cursor is in the visible text
     validate_virtcol();
-    int col = curwin->w_virtcol - curwin->w_skipcol;
+    long col = curwin->w_virtcol - curwin->w_skipcol + scrolloff_cols;
     int row = 0;
     if (col >= width1) {
       col -= width1;
-      ++row;
+      row++;
     }
     if (col > width2) {
-      row += col / width2;
+      row += (int)col / width2;
       col = col % width2;
     }
     if (row >= curwin->w_height) {
-      coladvance(curwin->w_virtcol - (row - curwin->w_height + 1) * width2);
+      curwin->w_curswant = curwin->w_virtcol - (row - curwin->w_height + 1) * width2;
+      coladvance(curwin->w_curswant);
     }
   }
   return moved;
@@ -1329,20 +1333,25 @@ bool scrollup(long line_count, int byfold)
   }
 
   if (curwin->w_cursor.lnum == curwin->w_topline && do_sms && curwin->w_skipcol > 0) {
-    // make sure the cursor is in a visible part of the line
+    int width1 = curwin->w_width - curwin_col_off();
+    int width2 = width1 + curwin_col_off2();
+    long so = curwin->w_p_so >= 0 ? curwin->w_p_so : p_so;
+    long scrolloff_cols = so == 0 ? 0 : width1 + (so - 1) * width2;
+
+    // Make sure the cursor is in a visible part of the line, taking
+    // 'scrolloff' into account, but using screen lines.
     validate_virtcol();
-    if (curwin->w_virtcol < curwin->w_skipcol + 3) {
-      int width1 = curwin->w_width - curwin_col_off();
-      int width2 = width1 + curwin_col_off2();
+    if (curwin->w_virtcol < curwin->w_skipcol + 3 + scrolloff_cols) {
       colnr_T col = curwin->w_virtcol;
 
       if (col < width1) {
         col += width1;
       }
-      while (col < curwin->w_skipcol + 3) {
+      while (col < curwin->w_skipcol + 3 + scrolloff_cols) {
         col += width2;
       }
-      coladvance(col);
+      curwin->w_curswant = col;
+      coladvance(curwin->w_curswant);
     }
   }