Retrospective commit from 2009-10-31.

Continue debugging set_cursor_from_row.
Continue debugging display of R2L glyph rows.

 xdisp.c (display_line): Always extend reversed_p rows to the end
 of line.
 (set_cursor_from_row): In R2L rows that don't display text, put
 the cursor on the rightmost glyph.

2 files changed, 23 insertions, 3 deletions

diff --git a/src/ChangeLog.bidi b/src/ChangeLog.bidi
index d4146e4c2e6..0df409481a7 100644
--- a/src/ChangeLog.bidi
+++ b/src/ChangeLog.bidi
@@ -1,3 +1,10 @@
+2009-10-31  Eli Zaretskii  <eliz@gnu.org>
+
+        * xdisp.c (display_line): Always extend reversed_p rows to the end
+        of line.
+        (set_cursor_from_row): In R2L rows that don't display text, put
+        the cursor on the rightmost glyph.
+
 2009-10-24  Eli Zaretskii  <eliz@gnu.org>
 
         * xdisp.c (set_cursor_from_row): Fix off-by-one error when
diff --git a/src/xdisp.c b/src/xdisp.c
index b44ce759870..6b2e046b82b 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -6575,8 +6575,6 @@ next_element_from_buffer (it)
              be reversed.  */
           if (it->glyph_row && (it->bidi_it.level_stack[0].level & 1) != 0)
             it->glyph_row->reversed_p = 1;
-          if (it->glyph_row && (it->bidi_it.level_stack[0].level & 1) != 0)
-            it->glyph_row->reversed_p = 1;
           bidi_get_next_char_visually (&it->bidi_it);
         }
       else
@@ -12527,6 +12525,14 @@ set_cursor_from_row (w, row, matrix, delta, delta_bytes, dy, dvpos)
           glyph_after = end;
         }
     }
+  else if (row->reversed_p)
+    {
+      /* In R2L rows that don't display text, put the cursor on the
+         rightmost glyph.  Case in point: an empty last line that is
+         part of an R2L paragraph.  */
+      cursor = end - 1;
+      x = -1;   /* will be computed below, at lable compute_x */
+    }
 
   /* Step 1: Try to find the glyph whose character position
      corresponds to point.  If that's not possible, find 2 glyphs
@@ -12701,6 +12707,9 @@ set_cursor_from_row (w, row, matrix, delta, delta_bytes, dy, dvpos)
                               cprop = Fget_char_property (make_number (gpos),
                                                           Qcursor,
                                                           glyph->object);
+                              /* FIXME: This loses the feature of the
+                                 unidirectional redisplay when the
+                                 property value was an integer.  */
                               if (!NILP (cprop))
                                 {
                                   cursor = glyph;
@@ -16529,7 +16538,6 @@ extend_face_to_end_of_line (it)
       Lisp_Object saved_object;
       enum display_element_type saved_what = it->what;
       int saved_face_id = it->face_id;
-      int text_len = it->glyph_row->used[TEXT_AREA];
 
       saved_object = it->object;
       saved_pos = it->position;
@@ -16905,6 +16913,11 @@ display_line (it)
 
           it->continuation_lines_width = 0;
           row->ends_at_zv_p = 1;
+          /* A row that displays right-to-left text must always have
+             its last face extended all the way to the end of line,
+             even if this row ends in ZV.  */
+          if (row->reversed_p)
+            extend_face_to_end_of_line (it);
           row_end = it->current;
           break;
         }