(back_comment): Make sure we only consider comment-starters

of the relevant style and return -1 in case of a failure to find the
beginning of the comment.
(Fforward_comment): If back_comment fails, go back to the position just
after the comment-end.
(scan_lists): Add comment describing a very minor bug.

diff --git a/src/ChangeLog b/src/ChangeLog
index bc8436677bb509b20f18390b0deeb44d4a8d4123..9e4f0ee87b2d54e4da1ac3f4f1f0b0b70529e36d 100644 (file)
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,12 @@
+2000-02-15  Stefan Monnier  <monnier@cs.yale.edu>
+
+       * syntax.c (back_comment): Make sure we only consider comment-starters
+       of the relevant style and return -1 in case of a failure to find the
+       beginning of the comment.
+       (Fforward_comment): If back_comment fails, go back to the position just
+       after the comment-end.
+       (scan_lists): Add comment describing a very minor bug.
+
 2000-02-14  Stefan Monnier  <monnier@cs.yale.edu>
 
        * minibuf.c (Ftry_completion, Fall_completions): Add a reference to

diff --git a/src/syntax.c b/src/syntax.c
index ceb48f3ec37994937b92ced4c93daec683ea6087..43f49dae9cfbe066a4951baa3581b25e3c121233 100644 (file)
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -508,6 +508,9 @@ back_comment (from, from_byte, stop, comnested, comstyle, charpos_ptr, bytepos_p
            code = Scomment;
          UPDATE_SYNTAX_TABLE_BACKWARD (from);
        }
+      else if (code == Scomment && comstyle != SYNTAX_COMMENT_STYLE (c))
+       /* Ignore comment starters of a different style.  */
+       continue;
 
       /* Ignore escaped characters, except comment-enders.  */
       if (code != Sendcomment && char_quoted (from, from_byte))
@@ -539,8 +542,7 @@ back_comment (from, from_byte, stop, comnested, comstyle, charpos_ptr, bytepos_p
        }
 
       if (code == Scomment)
-       /* FIXME: we should also check that the comstyle is correct
-          if the Scomment is a single-char. */
+       /* We've already checked that it is the relevant comstyle.  */
        {
          if (comnested && --nesting <= 0 && parity == 0 && !string_lossage)
            /* nested comments have to be balanced, so we don't need to
@@ -634,7 +636,7 @@ back_comment (from, from_byte, stop, comnested, comstyle, charpos_ptr, bytepos_p
   *charpos_ptr = from;
   *bytepos_ptr = from_byte;
 
-  return from;
+  return (from == comment_end) ? -1 : from;
 }
 \f
 DEFUN ("syntax-table-p", Fsyntax_table_p, Ssyntax_table_p, 1, 1, 0,
@@ -1795,6 +1797,8 @@ between them, return t; otherwise return nil.")
              INC_BOTH (from, from_byte);
              UPDATE_SYNTAX_TABLE_FORWARD (from);
            }
+         /* FIXME: here we ignore 2-char endcomments while we don't
+            when going backwards.  */
        }
       while (code == Swhitespace || code == Sendcomment);
 
@@ -1904,10 +1908,17 @@ between them, return t; otherwise return nil.")
            {
              found = back_comment (from, from_byte, stop, comnested, comstyle,
                                    &out_charpos, &out_bytepos);
-             if (found != -1)
-               from = out_charpos, from_byte = out_bytepos;
+             if (found == -1)
+               {
+                 /* Failure: we have to skip the one or two chars of the
+                    not-quite-endcomment.  */
+                 if (SYNTAX(c) != code)
+                   /* It was a two-char Sendcomment.  */
+                   INC_BOTH (from, from_byte);
+                 goto leave;
+               }
              /* We have skipped one comment.  */
-             break;
+             from = out_charpos, from_byte = out_bytepos;
            }
          else if (code != Swhitespace && code != Scomment)
            {
@@ -2227,6 +2238,12 @@ scan_lists (from, count, depth, sexpflag)
                break;
              found = back_comment (from, from_byte, stop, comnested, comstyle,
                                    &out_charpos, &out_bytepos);
+             /* FIXME:  if found == -1, then it really wasn't a comment-end.
+                For single-char Sendcomment, we can't do much about it apart
+                from skipping the char.
+                For 2-char endcomments, we could try again, taking both
+                chars as separate entities, but it's a lot of trouble
+                for very little gain, so we don't bother either.  -sm */
              if (found != -1)
                from = out_charpos, from_byte = out_bytepos;
              break;