Fix display of overlay arrow immediately after invisible text

* src/xdisp.c (overlay_arrow_at_row): Allow the overlay arrow's
marker position to be anywhere between the row's start and end
charpos.  This keeps the overlay arrow on display even when the
preceding text is invisible.  (Bug#54843)

1 files changed, 10 insertions, 1 deletions

diff --git a/src/xdisp.c b/src/xdisp.c
index f2b158f00e3..2c676c09827 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -16939,9 +16939,18 @@ overlay_arrow_at_row (struct it *it, struct glyph_row *row)
 
       val = find_symbol_value (var);
 
+      ptrdiff_t arrow_marker_pos;
       if (MARKERP (val)
           && current_buffer == XMARKER (val)->buffer
-          && (MATRIX_ROW_START_CHARPOS (row) == marker_position (val)))
+          && (arrow_marker_pos = marker_position (val),
+              /* Normally, the marker position will be at the row's
+                 start charpos.  But if the previous text lines are
+                 invisible, the row's start charpos includes those
+                 invisible lines, so we make a more general test that
+                 the marker position is anywhere between the start and
+                 the end character positions of this row.  */
+              (MATRIX_ROW_START_CHARPOS (row) <= arrow_marker_pos
+               && arrow_marker_pos < MATRIX_ROW_END_CHARPOS (row))))
         {
           if (FRAME_WINDOW_P (it->f)
               /* FIXME: if ROW->reversed_p is set, this should test