From: Eli Zaretskii <eliz@gnu.org>
Date: Fri, 12 Feb 2016 19:38:44 +0000 (+0200)
Subject: Fix redisplay after a large insertion
X-Git-Tag: emacs-25.0.91~11
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=d82f24b;p=emacs.git

Fix redisplay after a large insertion

* src/xdisp.c (redisplay_internal): Don't accept the results of
"optimization 3" if the cursor ends up in a partially visible
glyph row.  (Bug22637)
---

diff --git a/src/xdisp.c b/src/xdisp.c
index 8f1e98d99ef..840699d00fb 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -825,6 +825,7 @@ static Lisp_Object redisplay_window_1 (Lisp_Object);
 static bool set_cursor_from_row (struct window *, struct glyph_row *,
 				 struct glyph_matrix *, ptrdiff_t, ptrdiff_t,
 				 int, int);
+static bool cursor_row_fully_visible_p (struct window *, bool, bool);
 static bool update_menu_bar (struct frame *, bool, bool);
 static bool try_window_reusing_current_matrix (struct window *);
 static int try_window_id (struct window *);
@@ -13881,11 +13882,16 @@ redisplay_internal (void)
 	      eassert (this_line_vpos == it.vpos);
 	      eassert (this_line_y == it.current_y);
 	      set_cursor_from_row (w, row, w->current_matrix, 0, 0, 0, 0);
+	      if (cursor_row_fully_visible_p (w, false, true))
+		{
 #ifdef GLYPH_DEBUG
-	      *w->desired_matrix->method = 0;
-	      debug_method_add (w, "optimization 3");
+		  *w->desired_matrix->method = 0;
+		  debug_method_add (w, "optimization 3");
 #endif
-	      goto update;
+		  goto update;
+		}
+	      else
+		goto cancel;
 	    }
 	  else
 	    goto cancel;