Rewrite LRI/RLI/FSI handling in bidi_resolve_explicit_1.

diff --git a/src/bidi.c b/src/bidi.c
index 3c204a82b7867036281fa605e97a99d91d5fc9ab..8d26dde4cf2d3c38542231a77566aaab5b448e73 100644 (file)
--- a/src/bidi.c
+++ b/src/bidi.c
@@ -1836,59 +1836,6 @@ bidi_resolve_explicit_1 (struct bidi_it *bidi_it)
                     && bidi_it->next_en_type == WEAK_EN))
          type = WEAK_EN;
        break;
-      case FSI:        /* X5c */
-       end = string_p ? bidi_it->string.schars : ZV;
-       disp_pos = bidi_it->disp_pos;
-       disp_prop = bidi_it->disp_prop;
-       nchars = bidi_it->nchars;
-       ch_len = bidi_it->ch_len;
-       typ1 = find_first_strong_char (bidi_it->charpos, bidi_it->bytepos, end,
-                                      &disp_pos, &disp_prop, &bidi_it->string,
-                                      bidi_it->w, string_p, bidi_it->frame_window_p,
-                                      &ch_len, &nchars, true);
-       if (typ1 != STRONG_R && typ1 != STRONG_AL)
-         {
-           type = LRI;
-           goto fsi_as_lri;
-         }
-       else
-         type = RLI;
-       /* FALLTHROUGH */
-      case RLI:        /* X5a */
-       if (override == NEUTRAL_DIR)
-         bidi_it->type_after_w1 = type;
-       else    /* Unicode 8.0 correction.  */
-         bidi_it->type_after_w1 = (override == L2R ? STRONG_L : STRONG_R);
-       bidi_check_type (bidi_it->type_after_w1);
-       if (current_level < BIDI_MAXDEPTH
-           && bidi_it->invalid_levels == 0
-           && bidi_it->invalid_isolates == 0)
-         {
-           new_level = ((current_level + 1) & ~1) + 1;
-           bidi_it->isolate_level++;
-           bidi_push_embedding_level (bidi_it, new_level, NEUTRAL_DIR, true);
-         }
-       else
-         bidi_it->invalid_isolates++;
-       break;
-      case LRI:        /* X5b */
-    fsi_as_lri:
-       if (override == NEUTRAL_DIR)
-         bidi_it->type_after_w1 = type;
-       else    /* Unicode 8.0 correction.  */
-         bidi_it->type_after_w1 = (override == L2R ? STRONG_L : STRONG_R);
-       bidi_check_type (bidi_it->type_after_w1);
-       if (current_level < BIDI_MAXDEPTH - 1
-           && bidi_it->invalid_levels == 0
-           && bidi_it->invalid_isolates == 0)
-         {
-           new_level = ((current_level + 2) & ~1);
-           bidi_it->isolate_level++;
-           bidi_push_embedding_level (bidi_it, new_level, NEUTRAL_DIR, true);
-         }
-       else
-         bidi_it->invalid_isolates++;
-       break;
       case PDI:        /* X6a */
        if (bidi_it->invalid_isolates)
          {
@@ -1933,8 +1880,74 @@ bidi_resolve_explicit_1 (struct bidi_it *bidi_it)
          type = WEAK_EN;
        break;
       default:
-       /* Nothing.  */
-       break;
+       /* LRI, RLI, and FSI increment the embedding level of the
+          _following_ charcaters, so we must look at the type of the
+          previous character to support that.  */
+       switch (bidi_it->prev.orig_type)
+         {
+         case FSI:     /* X5c */
+           end = string_p ? bidi_it->string.schars : ZV;
+           disp_pos = bidi_it->disp_pos;
+           disp_prop = bidi_it->disp_prop;
+           nchars = bidi_it->nchars;
+           ch_len = bidi_it->ch_len;
+           typ1 = find_first_strong_char (bidi_it->charpos,
+                                          bidi_it->bytepos, end,
+                                          &disp_pos, &disp_prop,
+                                          &bidi_it->string, bidi_it->w,
+                                          string_p, bidi_it->frame_window_p,
+                                          &ch_len, &nchars, true);
+           if (typ1 != STRONG_R && typ1 != STRONG_AL)
+             {
+               type = LRI;
+               goto fsi_as_lri;
+             }
+           else
+             type = RLI;
+           /* FALLTHROUGH */
+         case RLI:     /* X5a */
+           eassert (bidi_it->prev.charpos == bidi_it->charpos - 1);
+           if (override == NEUTRAL_DIR)
+             bidi_it->type_after_w1 = type;
+           else        /* Unicode 8.0 correction.  */
+             bidi_it->type_after_w1 = (override == L2R ? STRONG_L : STRONG_R);
+           bidi_check_type (bidi_it->type_after_w1);
+           if (current_level < BIDI_MAXDEPTH
+               && bidi_it->invalid_levels == 0
+               && bidi_it->invalid_isolates == 0)
+             {
+               new_level = ((current_level + 1) & ~1) + 1;
+               bidi_it->isolate_level++;
+               bidi_push_embedding_level (bidi_it, new_level,
+                                          NEUTRAL_DIR, true);
+             }
+           else
+             bidi_it->invalid_isolates++;
+           break;
+         case LRI:     /* X5b */
+         fsi_as_lri:
+           eassert (bidi_it->prev.charpos == bidi_it->charpos - 1);
+           if (override == NEUTRAL_DIR)
+             bidi_it->type_after_w1 = type;
+           else        /* Unicode 8.0 correction.  */
+             bidi_it->type_after_w1 = (override == L2R ? STRONG_L : STRONG_R);
+           bidi_check_type (bidi_it->type_after_w1);
+           if (current_level < BIDI_MAXDEPTH - 1
+               && bidi_it->invalid_levels == 0
+               && bidi_it->invalid_isolates == 0)
+             {
+               new_level = ((current_level + 2) & ~1);
+               bidi_it->isolate_level++;
+               bidi_push_embedding_level (bidi_it, new_level,
+                                          NEUTRAL_DIR, true);
+             }
+           else
+             bidi_it->invalid_isolates++;
+           break;
+         default:
+           /* Nothing.  */
+           break;
+         }
     }
 
   bidi_it->type = type;
@@ -1983,6 +1996,7 @@ bidi_resolve_explicit (struct bidi_it *bidi_it)
                                                       + bidi_it->ch_len, s,
                                                       bidi_it->string.unibyte)))
        {
+         bidi_remember_char (&bidi_it->prev, bidi_it);
          /* This advances to the next character, skipping any
             characters covered by display strings.  */
          level = bidi_resolve_explicit_1 (bidi_it);