Fix cursor positioning in rows completely covered by display strings.

[bpt/emacs.git] / src / xdisp.c

diff --git a/src/xdisp.c b/src/xdisp.c
index 118480a..302a09d 100644 (file)
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -13800,16 +13800,31 @@ set_cursor_from_row (struct window *w, struct glyph_row *row,
 
            chprop = Fget_char_property (make_number (glyph_pos), Qcursor,
                                         glyph->object);
+           if (!NILP (chprop))
+             {
+               /* If the string came from a `display' text property,
+                  look up the buffer position of that property and
+                  use that position to update bpos_max, as if we
+                  actually saw such a position in one of the row's
+                  glyphs.  This helps with supporting integer values
+                  of `cursor' property on the display string in
+                  situations where most or all of the row's buffer
+                  text is completely covered by display properties,
+                  so that no glyph with valid buffer positions is
+                  ever seen in the row.  */
+               EMACS_INT prop_pos =
+                 string_buffer_position_lim (glyph->object, pos_before,
+                                             pos_after, 0);
+
+               if (prop_pos >= pos_before)
+                 bpos_max = prop_pos - 1;
+             }
            if (INTEGERP (chprop))
              {
                bpos_covered = bpos_max + XINT (chprop);
                /* If the `cursor' property covers buffer positions up
                   to and including point, we should display cursor on
-                  this glyph.  Note that overlays and text properties
-                  with string values stop bidi reordering, so every
-                  buffer position to the left of the string is always
-                  smaller than any position to the right of the
-                  string.  Therefore, if a `cursor' property on one
+                  this glyph.  Note that, if a `cursor' property on one
                   of the string's characters has an integer value, we
                   will break out of the loop below _before_ we get to
                   the position match above.  IOW, integer values of
@@ -13869,6 +13884,15 @@ set_cursor_from_row (struct window *w, struct glyph_row *row,
 
            chprop = Fget_char_property (make_number (glyph_pos), Qcursor,
                                         glyph->object);
+           if (!NILP (chprop))
+             {
+               EMACS_INT prop_pos =
+                 string_buffer_position_lim (glyph->object, pos_before,
+                                             pos_after, 0);
+
+               if (prop_pos >= pos_before)
+                 bpos_max = prop_pos - 1;
+             }
            if (INTEGERP (chprop))
              {
                bpos_covered = bpos_max + XINT (chprop);