patch 9.1.0357: Page scrolling should place cursor at window boundaries

Problem:  Page scrolling does not always place the cursor at the top or
          bottom of the window (Mathias Rav)
Solution: Place the cursor at the top or bottom of the window.
          (Luuk van Baal)

fixes: #14585
closes: #14586

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
index a234fca..1b6e003 100644
--- a/src/move.c
+++ b/src/move.c
@@ -3244,17 +3244,6 @@
 	    cursor_down_inner(curwin, curscount);
 	else
 	    cursor_up_inner(curwin, curscount);
-
-	if (get_scrolloff_value() > 0)
-	    cursor_correct();
-#ifdef FEAT_FOLDING
-	// Move cursor to first line of closed fold.
-	foldAdjustCursor();
-#endif
-
-	nochange = nochange
-	    && prev_col == curwin->w_cursor.col
-	    && prev_lnum == curwin->w_cursor.lnum;
     }
     else
     {
@@ -3262,8 +3251,23 @@
 	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);
+
+	// Place cursor at top or bottom of window.
+	validate_botline();
+	curwin->w_cursor.lnum = (dir == FORWARD ? curwin->w_topline
+						    : curwin->w_botline - 1);
     }
 
+    if (get_scrolloff_value() > 0)
+	cursor_correct();
+#ifdef FEAT_FOLDING
+    // Move cursor to first line of closed fold.
+    foldAdjustCursor();
+#endif
+    nochange = nochange
+	&& prev_col == curwin->w_cursor.col
+	&& prev_lnum == curwin->w_cursor.lnum;
+
     // Error if both the viewport and cursor did not change.
     if (nochange)
 	beep_flush();