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.

2 files changed, 31 insertions, 11 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index b6ae117c8b2..5ac0f885d8e 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,10 @@
+2013-05-06  Eli Zaretskii  <eliz@gnu.org>
+
+        * 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  <eggert@cs.ucla.edu>
 
         * unexelf.c: Fix some 32-bit integer problems, notably when debugging.
diff --git a/src/xdisp.c b/src/xdisp.c
index 6900c35c07c..c7a25873272 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -1392,23 +1392,34 @@ pos_visible_p (struct window *w, ptrdiff_t charpos, int *x, int *y,
               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 @@ pos_visible_p (struct window *w, ptrdiff_t charpos, int *x, int *y,
                      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 @@ pos_visible_p (struct window *w, ptrdiff_t charpos, int *x, int *y,
                      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]