Discovery of replacing display properties now uses the same code

as the display engine.  Tested OK with display properties whose
value is a list.

 src/dispextern.h (struct bidi_it): New member frame_window_p.
 (bidi_init_it, compute_display_string_pos): Update prototypes.
 src/bidi.c (bidi_fetch_char): Accept additional argument
 FRAME_WINDOW_P and pass it to compute_display_string_pos.  All
 callers changed.
 (bidi_init_it): Accept additional argument FRAME_WINDOW_P and use
 it to initialize the frame_window_p member of struct bidi_it.
 src/xdisp.c (handle_display_spec): New function, refactored from the
 last portion of handle_display_prop.
 (compute_display_string_pos): Accept additional argument
 FRAME_WINDOW_P.  Call handle_display_spec to determine whether the
 value of a `display' property is a "replacing spec".
 (handle_single_display_spec): Accept 2 additional arguments BUFPOS
 and FRAME_WINDOW_P.  If IT is NULL, don't set up the iterator from
 the display property, but just return a value indicating whether
 the display property will replace the characters it covers.
 (Fcurrent_bidi_paragraph_direction): Initialize the nchars and
 frame_window_p members of struct bidi_it.

1 files changed, 3 insertions, 2 deletions

diff --git a/src/dispextern.h b/src/dispextern.h
index f5036169f75..6c09f21a78f 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -1847,6 +1847,7 @@ struct bidi_it {
   int first_elt;                /* if non-zero, examine current char first */
   bidi_dir_t paragraph_dir;     /* current paragraph direction */
   int new_paragraph;            /* if non-zero, we expect a new paragraph */
+  int frame_window_p;           /* non-zero if displaying on a GUI frame */
   EMACS_INT separator_limit;    /* where paragraph separator should end */
   EMACS_INT disp_pos;           /* position of display string after ch */
 };
@@ -2945,7 +2946,7 @@ enum tool_bar_item_image
 
 /* Defined in bidi.c */
 
-extern void bidi_init_it (EMACS_INT, EMACS_INT, struct bidi_it *);
+extern void bidi_init_it (EMACS_INT, EMACS_INT, int, struct bidi_it *);
 extern void bidi_move_to_visually_next (struct bidi_it *);
 extern void bidi_paragraph_init (bidi_dir_t, struct bidi_it *, int);
 extern int  bidi_mirror_char (int);
@@ -3006,7 +3007,7 @@ extern void reseat_at_previous_visible_line_start (struct it *);
 extern Lisp_Object lookup_glyphless_char_display (int, struct it *);
 extern int calc_pixel_width_or_height (double *, struct it *, Lisp_Object,
                                        struct font *, int, int *);
-extern EMACS_INT compute_display_string_pos (EMACS_INT);
+extern EMACS_INT compute_display_string_pos (EMACS_INT, int);
 extern EMACS_INT compute_display_string_end (EMACS_INT);
 
 #ifdef HAVE_WINDOW_SYSTEM