(note_mouse_highlight): Call mouse_face_overlay_overlaps

to detect a case where we have to highlight a different region
despite not having left the currently highlighted region.
Set mouse_face_overlay in the x_display_info.
(x_term_init): Initialze the x_display_info's mouse_face_overlay.

1 files changed, 13 insertions, 3 deletions

diff --git a/src/xterm.c b/src/xterm.c
index ef4801fbb18..fc09897de01 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -6723,7 +6723,7 @@ note_mouse_highlight (f, x, y)
 
       /* Check for mouse-face and help-echo.  */
       {
-        Lisp_Object mouse_face, overlay, position;
+        Lisp_Object mouse_face = Qnil, overlay, position;
         Lisp_Object *overlay_vec;
         int len, noverlays;
         struct buffer *obuf;
@@ -6769,7 +6769,14 @@ note_mouse_highlight (f, x, y)
                    || hpos >= dpyinfo->mouse_face_beg_col)
                && (vpos < dpyinfo->mouse_face_end_row
                    || hpos < dpyinfo->mouse_face_end_col
-                   || dpyinfo->mouse_face_past_end)))
+                   || dpyinfo->mouse_face_past_end))
+            /* If there exists an overlay with mouse-face overlapping
+               the one we are currently highlighting, we have to
+               check if we enter the overlapping overlay, and then
+               highlight only that.  */
+            || (OVERLAYP (dpyinfo->mouse_face_overlay)
+                && mouse_face_overlay_overlaps (dpyinfo->mouse_face_overlay)))
+          
           {
             /* Clear the display of the old active region, if any.  */
             clear_mouse_face (dpyinfo);
@@ -6790,8 +6797,10 @@ note_mouse_highlight (f, x, y)
             if (NILP (overlay))
               mouse_face = Fget_text_property (position, Qmouse_face, w->buffer);
 
+            dpyinfo->mouse_face_overlay = overlay;
+            
             /* Handle the overlay case.  */
-            if (! NILP (overlay))
+            if (!NILP (overlay))
               {
                 /* Find the range of text around this char that
                    should be active.  */
@@ -13779,6 +13788,7 @@ x_term_init (display_name, xrm_option, resource_name)
   dpyinfo->mouse_face_end_row = dpyinfo->mouse_face_end_col = -1;
   dpyinfo->mouse_face_face_id = DEFAULT_FACE_ID;
   dpyinfo->mouse_face_window = Qnil;
+  dpyinfo->mouse_face_overlay = Qnil;
   dpyinfo->mouse_face_mouse_x = dpyinfo->mouse_face_mouse_y = 0;
   dpyinfo->mouse_face_defer = 0;
   dpyinfo->x_focus_frame = 0;