Fix display of overlapping window-specific overlays

* src/keyboard.c (adjust_point_for_property): When adjusting point
due to display strings, ignore overlays that are specific to
windows other than the currently selected one.

* src/xdisp.c (handle_single_display_spec): If the display
property comes from an overlay, arrange for buffer iteration to
resume only after the end of that overlay.  (Bug#20607)

2 files changed, 16 insertions, 1 deletions

diff --git a/src/keyboard.c b/src/keyboard.c
index 77f7fb97898..eb66c445559 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -1702,7 +1702,8 @@ adjust_point_for_property (ptrdiff_t last_pt, bool modified)
       if (check_display
           && PT > BEGV && PT < ZV
           && !NILP (val = get_char_property_and_overlay
-                              (make_number (PT), Qdisplay, Qnil, &overlay))
+                              (make_number (PT), Qdisplay, selected_window,
+                               &overlay))
           && display_prop_intangible_p (val, overlay, PT, PT_BYTE)
           && (!OVERLAYP (overlay)
               ? get_property_and_range (PT, Qdisplay, &val, &beg, &end, Qnil)
diff --git a/src/xdisp.c b/src/xdisp.c
index c2f0b747c6e..8123719ed48 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -4899,6 +4899,20 @@ handle_single_display_spec (struct it *it, Lisp_Object spec, Lisp_Object object,
     {
       start_pos = *position;
       *position = display_prop_end (it, object, start_pos);
+      /* If the display property comes from an overlay, don't consider
+         any potential stop_charpos values before the end of that
+         overlay.  Since display_prop_end will happily find another
+         'display' property coming from some other overlay or text
+         property on buffer positions before this overlay's end, we
+         need to ignore them, or else we risk displaying this
+         overlay's display string/image twice.  */
+      if (!NILP (overlay))
+        {
+          ptrdiff_t ovendpos = OVERLAY_POSITION (OVERLAY_END (overlay));
+
+          if (ovendpos > CHARPOS (*position))
+            SET_TEXT_POS (*position, ovendpos, CHAR_TO_BYTE (ovendpos));
+        }
     }
   value = Qnil;