Avoid recentering when point enters invisible text at BOL

* src/xdisp.c (try_cursor_movement): Don't say we must scroll when
point is inside invisible text at beginning of a glyph row.
(Bug#58793)

1 files changed, 21 insertions, 13 deletions

diff --git a/src/xdisp.c b/src/xdisp.c
index 557cb606317..32675cd76ac 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -18926,7 +18926,7 @@ try_cursor_movement (Lisp_Object window, struct text_pos startp,
               while (MATRIX_ROW_BOTTOM_Y (row) < last_y
                      && MATRIX_ROW_END_CHARPOS (row) == PT
                      && row < MATRIX_MODE_LINE_ROW (w->current_matrix)
-                     && MATRIX_ROW_START_CHARPOS (row+1) == PT
+                     && MATRIX_ROW_START_CHARPOS (row+1) >= PT
                      && !cursor_row_p (row))
                 ++row;
 
@@ -19023,7 +19023,12 @@ try_cursor_movement (Lisp_Object window, struct text_pos startp,
                  rc = CURSOR_MOVEMENT_SUCCESS;
             }
 
-          if (PT < MATRIX_ROW_START_CHARPOS (row)
+          if ((PT < MATRIX_ROW_START_CHARPOS (row)
+               && (row == MATRIX_FIRST_TEXT_ROW (w->current_matrix)
+                   /* Don't give up if point is inside invisible text
+                      at the beginning of its glyph row.  */
+                   || (MATRIX_ROW_END_CHARPOS (row-1)
+                       == MATRIX_ROW_START_CHARPOS (row))))
               || PT > MATRIX_ROW_END_CHARPOS (row))
             {
               /* if PT is not in the glyph row, give up.  */
@@ -19105,12 +19110,23 @@ try_cursor_movement (Lisp_Object window, struct text_pos startp,
                  continuation lines' rows is implemented for
                  bidi-reordered rows.  */
               bool rv = false;
+              bool pt_invis = false;
+              Lisp_Object val = get_char_property_and_overlay (make_fixnum (PT),
+                                                               Qinvisible,
+                                                               Qnil, NULL);
+
+              if (TEXT_PROP_MEANS_INVISIBLE (val) != 0)
+                pt_invis = true;
 
               do
                 {
                   bool at_zv_p = false, exact_match_p = false;
 
-                  if (MATRIX_ROW_START_CHARPOS (row) <= PT
+                  /* If point is in invisible text, we cannot assume
+                     it must be after row's start position, since the
+                     row could have invisible text at its beginning
+                     where point is located.  */
+                  if ((pt_invis || MATRIX_ROW_START_CHARPOS (row) <= PT)
                       && PT <= MATRIX_ROW_END_CHARPOS (row)
                       && cursor_row_p (row))
                     rv |= set_cursor_from_row (w, row, w->current_matrix,
@@ -19142,16 +19158,8 @@ try_cursor_movement (Lisp_Object window, struct text_pos startp,
                              invisible text?  In that case, we trust
                              'set_cursor_from_row' to do its job and
                              find the best position for the cursor.  */
-                          if (!exact_match_p)
-                            {
-                              Lisp_Object val =
-                                get_char_property_and_overlay (make_fixnum (PT),
-                                                               Qinvisible,
-                                                               Qnil, NULL);
-
-                              if (TEXT_PROP_MEANS_INVISIBLE (val) != 0)
-                                exact_match_p = true;
-                            }
+                          if (!exact_match_p && pt_invis)
+                            exact_match_p = true;
                         }
                       if (at_zv_p || exact_match_p)
                         {