[Emacs-diffs] /srv/bzr/emacs/trunk r112480: Fix bug #14241 with posn-at-point at the beginning of an image display prop.

[Eli Zaretskii]

------------------------------------------------------------
revno: 112480
fixes bug: http://debbugs.gnu.org/14241
committer: Eli Zaretskii <address@hidden>
branch nick: trunk
timestamp: Mon 2013-05-06 20:11:07 +0300
message:
  Fix bug #14241 with posn-at-point at the beginning of an image display prop.
  
   src/xdisp.c (pos_visible_p): Use the special code for finding the
   beginning of a display property or overlay for any "replacing"
   display property, not just for display strings.  This solves
   incorrect reporting of position by posn-at-point.
modified:
  src/ChangeLog
  src/xdisp.c

=== modified file 'src/ChangeLog'
--- a/src/ChangeLog     2013-05-06 04:52:00 +0000
+++ b/src/ChangeLog     2013-05-06 17:11:07 +0000
@@ -1,3 +1,10 @@
+2013-05-06  Eli Zaretskii  <address@hidden>
+
+       * xdisp.c (pos_visible_p): Use the special code for finding the
+       beginning of a display property or overlay for any "replacing"
+       display property, not just for display strings.  This solves
+       incorrect reporting of position by posn-at-point.  (Bug#14241)
+
 2013-05-06  Paul Eggert  <address@hidden>
 
        * unexelf.c: Fix some 32-bit integer problems, notably when debugging.

=== modified file 'src/xdisp.c'
--- a/src/xdisp.c       2013-05-05 17:41:09 +0000
+++ b/src/xdisp.c       2013-05-06 17:11:07 +0000
@@ -1392,23 +1392,34 @@
              Lisp_Object cpos = make_number (charpos);
              Lisp_Object spec = Fget_char_property (cpos, Qdisplay, Qnil);
              Lisp_Object string = string_from_display_spec (spec);
+             struct text_pos tpos;
+             int replacing_spec_p;
              bool newline_in_string
                = (STRINGP (string)
                   && memchr (SDATA (string), '\n', SBYTES (string)));
+
+             SET_TEXT_POS (tpos, charpos, CHAR_TO_BYTE (charpos));
+             replacing_spec_p
+               = (!NILP (spec)
+                  && handle_display_spec (NULL, spec, Qnil, Qnil, &tpos,
+                                          charpos, FRAME_WINDOW_P (it.f)));
              /* The tricky code below is needed because there's a
                 discrepancy between move_it_to and how we set cursor
-                when the display line ends in a newline from a
-                display string.  move_it_to will stop _after_ such
-                display strings, whereas set_cursor_from_row
-                conspires with cursor_row_p to place the cursor on
-                the first glyph produced from the display string.  */
+                when PT is at the beginning of a portion of text
+                covered by a display property or an overlay with a
+                display property, or the display line ends in a
+                newline from a display string.  move_it_to will stop
+                _after_ such display strings, whereas
+                set_cursor_from_row conspires with cursor_row_p to
+                place the cursor on the first glyph produced from the
+                display string.  */
 
              /* We have overshoot PT because it is covered by a
-                display property whose value is a string.  If the
-                string includes embedded newlines, we are also in the
-                wrong display line.  Backtrack to the correct line,
-                where the display string begins.  */
-             if (newline_in_string)
+                display property that replaces the text it covers.
+                If the string includes embedded newlines, we are also
+                in the wrong display line.  Backtrack to the correct
+                line, where the display property begins.  */
+             if (replacing_spec_p)
                {
                  Lisp_Object startpos, endpos;
                  EMACS_INT start, end;
@@ -1434,7 +1445,8 @@
                     rightmost character on a line that is
                     continued or word-wrapped.  */
                  if (it3.method == GET_FROM_BUFFER
-                     && it3.c == '\n')
+                     && (it3.c == '\n'
+                         || FETCH_BYTE (IT_BYTEPOS (it3)) == '\n'))
                    move_it_by_lines (&it3, 1);
                  else if (move_it_in_display_line_to (&it3, -1,
                                                       it3.current_x
@@ -1502,6 +1514,7 @@
                     produced from the string, until we find the
                     rightmost glyph not from the string.  */
                  if (it3_moved
+                     && newline_in_string
                      && IT_CHARPOS (it3) != charpos && EQ (it3.object, string))
                    {
                      struct glyph *g = it3.glyph_row->glyphs[TEXT_AREA]