# HG changeset patch
# User Christian Brabandt <cb@256bit.org>
# Date 1715420702 -7200
# Node ID 08f7c9428f8224d6b24c60f4da1fd12c6354e852
# Parent  ee6031d181daaa3ba533fd900c0ff2ea0f6e46a6
patch 9.1.0407: Stuck with long line and half-page scrolling

Commit: https://github.com/vim/vim/commit/58448e09be497a8abb595ae309b6edfbc8e0e05a
Author: Luuk van Baal <luukvbaal@gmail.com>
Date:   Sat May 11 11:27:52 2024 +0200

    patch 9.1.0407: Stuck with long line and half-page scrolling

    Problem:  No scrolling happens with half-page scrolling with line
              filling entire window when 'smoothscroll' is disabled.
              (Mathias Rav, after v9.1.0285)
    Solution: Adjust amount to move cursor by so that it is moved the same
              number of lines as was scrolled, even when scrolling different
              number of lines than requested with 'nosmoothscroll'.

    fixes: #14743
    closes: #14746

    Signed-off-by: Luuk van Baal <luukvbaal@gmail.com>
    Signed-off-by: Christian Brabandt <cb@256bit.org>

diff --git a/src/move.c b/src/move.c
--- a/src/move.c
+++ b/src/move.c
@@ -3158,9 +3158,10 @@ static int get_scroll_overlap(int dir)
 
 /*
  * Scroll "count" lines with 'smoothscroll' in direction "dir". Return TRUE
- * when scrolling happened.
+ * when scrolling happened. Adjust "curscount" for scrolling different amount of
+ * lines when 'smoothscroll' is disabled.
  */
-static int scroll_with_sms(int dir, long count)
+static int scroll_with_sms(int dir, long count, long *curscount)
 {
     int		prev_sms = curwin->w_p_sms;
     colnr_T	prev_skipcol = curwin->w_skipcol;
@@ -3183,7 +3184,10 @@ static int scroll_with_sms(int dir, long
 	    fixdir = dir * -1;
 	while (curwin->w_skipcol > 0
 	    && curwin->w_topline < curbuf->b_ml.ml_line_count)
+	{
 	    scroll_redraw(fixdir == FORWARD, 1);
+	    *curscount += (fixdir == dir ? 1 : -1);
+	}
     }
     curwin->w_p_sms = prev_sms;
 
@@ -3220,7 +3224,7 @@ pagescroll(int dir, long count, int half
 	    curwin->w_p_scr = MIN(curwin->w_height, count);
 	count = MIN(curwin->w_height, curwin->w_p_scr);
 
-	int curscount = count;
+	long curscount = count;
 	// Adjust count so as to not reveal end of buffer lines.
 	if (dir == FORWARD
 		    && (curwin->w_topline + curwin->w_height + count > buflen
@@ -3240,7 +3244,7 @@ pagescroll(int dir, long count, int half
 	// (Try to) scroll the window unless already at the end of the buffer.
 	if (count > 0)
 	{
-	    nochange = scroll_with_sms(dir, count);
+	    nochange = scroll_with_sms(dir, count, &curscount);
 	    curwin->w_cursor.lnum = prev_lnum;
 	    curwin->w_cursor.col = prev_col;
 	    curwin->w_curswant = prev_curswant;
@@ -3259,7 +3263,7 @@ pagescroll(int dir, long count, int half
 	// Scroll [count] times 'window' or current window height lines.
 	count *= ((ONE_WINDOW && p_window > 0 && p_window < Rows - 1) ?
 				MAX(1, p_window - 2) : get_scroll_overlap(dir));
-	nochange = scroll_with_sms(dir, count);
+	nochange = scroll_with_sms(dir, count, &count);
 
 	// Place cursor at top or bottom of window.
 	validate_botline();
diff --git a/src/testdir/test_normal.vim b/src/testdir/test_normal.vim
--- a/src/testdir/test_normal.vim
+++ b/src/testdir/test_normal.vim
@@ -4260,4 +4260,12 @@ func Test_page_cursor_topbot()
   bwipe!
 endfunc
 
+" Test for Ctrl-D with long line
+func Test_halfpage_longline()
+  10new
+  call setline(1, ['long'->repeat(1000), 'short'])
+  exe "norm! \<C-D>"
+  call assert_equal(2, line('.'))
+  bwipe!
+endfunc
 " vim: shiftwidth=2 sts=2 expandtab nofoldenable
diff --git a/src/version.c b/src/version.c
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    407,
+/**/
     406,
 /**/
     405,