1 files changed, 28 insertions, 16 deletions

diff --git a/src/bidi.c b/src/bidi.c
index 697ebb92856..ae5143b37e0 100644
--- a/src/bidi.c
+++ b/src/bidi.c
@@ -792,6 +792,7 @@ bidi_init_it (EMACS_INT charpos, EMACS_INT bytepos, int frame_window_p,
     bidi_it->prev_for_neutral.orig_type = UNKNOWN_BT;
   bidi_it->sor = L2R;	 /* FIXME: should it be user-selectable? */
   bidi_it->disp_pos = -1;	/* invalid/unknown */
+  bidi_it->disp_prop_p = 0;
   /* We can only shrink the cache if we are at the bottom level of its
      "stack".  */
   if (bidi_cache_start == 0)
@@ -874,14 +875,16 @@ bidi_char_at_pos (EMACS_INT bytepos, const unsigned char *s, int unibyte)
    covered characters as a single character u+FFFC, and return their
    combined length in CH_LEN and NCHARS.  DISP_POS specifies the
    character position of the next display string, or -1 if not yet
-   computed.  When the next character is at or beyond that position,
-   the function updates DISP_POS with the position of the next display
-   string.  STRING->s is the C string to iterate, or NULL if iterating
-   over a buffer or a Lisp string; in the latter case, STRING->lstring
-   is the Lisp string.  */
+   computed.  DISP_PROP_P non-zero means that there's really a display
+   string at DISP_POS, as opposed to when we searched till DISP_POS
+   without findingone.  When the next character is at or beyond that
+   position, the function updates DISP_POS with the position of the
+   next display string.  STRING->s is the C string to iterate, or NULL
+   if iterating over a buffer or a Lisp string; in the latter case,
+   STRING->lstring is the Lisp string.  */
 static inline int
 bidi_fetch_char (EMACS_INT bytepos, EMACS_INT charpos, EMACS_INT *disp_pos,
-		 struct bidi_string_data *string,
+		 int *disp_prop_p, struct bidi_string_data *string,
 		 int frame_window_p, EMACS_INT *ch_len, EMACS_INT *nchars)
 {
   int ch;
@@ -894,7 +897,8 @@ bidi_fetch_char (EMACS_INT bytepos, EMACS_INT charpos, EMACS_INT *disp_pos,
   if (charpos < endpos && charpos > *disp_pos)
     {
       SET_TEXT_POS (pos, charpos, bytepos);
-      *disp_pos = compute_display_string_pos (&pos, string, frame_window_p);
+      *disp_pos = compute_display_string_pos (&pos, string, frame_window_p,
+					      disp_prop_p);
     }
 
   /* Fetch the character at BYTEPOS.  */
@@ -904,8 +908,9 @@ bidi_fetch_char (EMACS_INT bytepos, EMACS_INT charpos, EMACS_INT *disp_pos,
       *ch_len = 1;
       *nchars = 1;
       *disp_pos = endpos;
+      *disp_prop_p = 0;
     }
-  else if (charpos >= *disp_pos)
+  else if (charpos >= *disp_pos && *disp_prop_p)
     {
       EMACS_INT disp_end_pos;
 
@@ -972,10 +977,12 @@ bidi_fetch_char (EMACS_INT bytepos, EMACS_INT charpos, EMACS_INT *disp_pos,
 
   /* If we just entered a run of characters covered by a display
      string, compute the position of the next display string.  */
-  if (charpos + *nchars <= endpos && charpos + *nchars > *disp_pos)
+  if (charpos + *nchars <= endpos && charpos + *nchars > *disp_pos
+      && *disp_prop_p)
     {
       SET_TEXT_POS (pos, charpos + *nchars, bytepos + *ch_len);
-      *disp_pos = compute_display_string_pos (&pos, string, frame_window_p);
+      *disp_pos = compute_display_string_pos (&pos, string, frame_window_p,
+					      disp_prop_p);
     }
 
   return ch;
@@ -1083,6 +1090,7 @@ bidi_paragraph_init (bidi_dir_t dir, struct bidi_it *bidi_it, int no_default_p)
       int ch;
       EMACS_INT ch_len, nchars;
       EMACS_INT pos, disp_pos = -1;
+      int disp_prop_p = 0;
       bidi_type_t type;
       const unsigned char *s;
 
@@ -1130,7 +1138,8 @@ bidi_paragraph_init (bidi_dir_t dir, struct bidi_it *bidi_it, int no_default_p)
 	bytepos = pstartbyte;
 	if (!string_p)
 	  pos = BYTE_TO_CHAR (bytepos);
-	ch = bidi_fetch_char (bytepos, pos, &disp_pos, &bidi_it->string,
+	ch = bidi_fetch_char (bytepos, pos, &disp_pos, &disp_prop_p,
+			      &bidi_it->string,
 			      bidi_it->frame_window_p, &ch_len, &nchars);
 	type = bidi_get_type (ch, NEUTRAL_DIR);
 
@@ -1157,7 +1166,8 @@ bidi_paragraph_init (bidi_dir_t dir, struct bidi_it *bidi_it, int no_default_p)
 		&& bidi_at_paragraph_end (pos, bytepos) >= -1)
 	      break;
 	    /* Fetch next character and advance to get past it.  */
-	    ch = bidi_fetch_char (bytepos, pos, &disp_pos, &bidi_it->string,
+	    ch = bidi_fetch_char (bytepos, pos, &disp_pos,
+				  &disp_prop_p, &bidi_it->string,
 				  bidi_it->frame_window_p, &ch_len, &nchars);
 	    pos += nchars;
 	    bytepos += ch_len;
@@ -1290,6 +1300,7 @@ bidi_resolve_explicit_1 (struct bidi_it *bidi_it)
       bidi_it->ch_len = 1;
       bidi_it->nchars = 1;
       bidi_it->disp_pos = (string_p ? bidi_it->string.schars : ZV);
+      bidi_it->disp_prop_p = 0;
     }
   else
     {
@@ -1297,8 +1308,8 @@ bidi_resolve_explicit_1 (struct bidi_it *bidi_it)
 	 display string, treat the entire run of covered characters as
 	 a single character u+FFFC.  */
       curchar = bidi_fetch_char (bidi_it->bytepos, bidi_it->charpos,
-				 &bidi_it->disp_pos, &bidi_it->string,
-				 bidi_it->frame_window_p,
+				 &bidi_it->disp_pos, &bidi_it->disp_prop_p,
+				 &bidi_it->string, bidi_it->frame_window_p,
 				 &bidi_it->ch_len, &bidi_it->nchars);
     }
   bidi_it->ch = curchar;
@@ -2032,12 +2043,13 @@ bidi_level_of_next_char (struct bidi_it *bidi_it)
       struct bidi_string_data bs = bidi_it->string;
       bidi_type_t chtype;
       int fwp = bidi_it->frame_window_p;
+      int dpp = bidi_it->disp_prop_p;
 
       if (bidi_it->nchars <= 0)
 	abort ();
       do {
-	ch = bidi_fetch_char (bpos += clen, cpos += nc, &disp_pos, &bs, fwp,
-			      &clen, &nc);
+	ch = bidi_fetch_char (bpos += clen, cpos += nc, &disp_pos, &dpp, &bs,
+			      fwp, &clen, &nc);
 	if (ch == '\n' || ch == BIDI_EOB /* || ch == LINESEP_CHAR */)
 	  chtype = NEUTRAL_B;
 	else