patch 9.0.1983: scrolling inactive window not possible with cursorbind

Problem:  Scrolling non-current window using mouse is inconsistent
          depending on 'scrollbind'/'scrolloff' and different from GUI
          vertical scrollbar when 'cursorbind' is set.
Solution: Don't move cursor in non-current windows for 'cursorbind' if
          cursor in the current window didn't move.

closes: #13219
closes: #13210

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: zeertzjq <zeertzjq@outlook.com>

src/move.c

@@ -3571,6 +3571,14 @@ halfpage(int flag, linenr_T Prenum)
     void
 do_check_cursorbind(void)
 {
+    static win_T	*prev_curwin = NULL;
+    static pos_T	prev_cursor = {0, 0, 0};
+
+    if (curwin == prev_curwin && EQUAL_POS(curwin->w_cursor, prev_cursor))
+	return;
+    prev_curwin = curwin;
+    prev_cursor = curwin->w_cursor;
+
     linenr_T	line = curwin->w_cursor.lnum;
     colnr_T	col = curwin->w_cursor.col;
     colnr_T	coladd = curwin->w_cursor.coladd;

src/testdir/test_scroll_opt.vim

@@ -1,4 +1,4 @@
-" Test for reset 'scroll' and 'smoothscroll'
+" Test for 'scroll', 'scrolloff', 'smoothscroll', etc.
 
 source check.vim
 source screendump.vim
@@ -55,6 +55,60 @@ func Test_scolloff_even_line_count()
   bwipe!
 endfunc
 
+func Test_mouse_scroll_inactive_with_cursorbind()
+  for scb in [0, 1]
+    for so in [0, 1, 2]
+      let msg = $'scb={scb} so={so}'
+
+      new | only
+      let w1 = win_getid()
+      setlocal cursorbind
+      let &l:scb = scb
+      let &l:so = so
+      call setline(1, range(101, 109))
+      rightbelow vnew
+      let w2 = win_getid()
+      setlocal cursorbind
+      let &l:scb = scb
+      let &l:so = so
+      call setline(1, range(101, 109))
+
+      normal! $
+      call assert_equal(3, col('.', w1), msg)
+      call assert_equal(3, col('.', w2), msg)
+      call test_setmouse(1, 1)
+      call feedkeys("\<ScrollWheelDown>", 'xt')
+      call assert_equal(4, line('w0', w1), msg)
+      call assert_equal(4 + so, line('.', w1), msg)
+      call assert_equal(1, line('w0', w2), msg)
+      call assert_equal(1, line('.', w2), msg)
+      call feedkeys("\<ScrollWheelDown>", 'xt')
+      call assert_equal(7, line('w0', w1), msg)
+      call assert_equal(7 + so, line('.', w1), msg)
+      call assert_equal(1, line('w0', w2), msg)
+      call assert_equal(1, line('.', w2), msg)
+      call feedkeys("\<ScrollWheelUp>", 'xt')
+      call assert_equal(4, line('w0', w1), msg)
+      call assert_equal(7 + so, line('.', w1), msg)
+      call assert_equal(1, line('w0', w2), msg)
+      call assert_equal(1, line('.', w2), msg)
+      call feedkeys("\<ScrollWheelUp>", 'xt')
+      call assert_equal(1, line('w0', w1), msg)
+      call assert_equal(7 + so, line('.', w1), msg)
+      call assert_equal(1, line('w0', w2), msg)
+      call assert_equal(1, line('.', w2), msg)
+      normal! 0
+      call assert_equal(1, line('.', w1), msg)
+      call assert_equal(1, col('.', w1), msg)
+      call assert_equal(1, line('.', w2), msg)
+      call assert_equal(1, col('.', w2), msg)
+
+      bwipe!
+      bwipe!
+    endfor
+  endfor
+endfunc
+
 func Test_CtrlE_CtrlY_stop_at_end()
   enew
   call setline(1, ['one', 'two'])

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1983,
 /**/
     1982,
 /**/