emacs-27 f946e48 1/2: Fix face extension past EOL in overlay strings

[Eli Zaretskii]

branch: emacs-27
commit f946e48bf5bfe051e77eee4c3c19633cbbb6e8c2
Author: Eli Zaretskii <eliz@gnu.org>
Commit: Eli Zaretskii <eliz@gnu.org>

    Fix face extension past EOL in overlay strings
    
    * src/xdisp.c (face_at_pos): Pass ATTR_FILTER to
    face_for_overlay_string.
    * src/xfaces.c (face_for_overlay_string): Accept an additional
    argument ATTR_INDEX and pass it to merge_face_ref for merging the
    face at POS.  This ensures a face from buffer text will not be
    merged unless it specifies the :extend attribute.  (Bug#42552)
    * src/dispextern.h (face_for_overlay_string): Adjust prototype.
    
    (cherry picked from commit 35564bea4d73bc266743216599d01d644aed6fd8)
---
 src/dispextern.h | 2 +-
 src/xdisp.c      | 2 +-
 src/xfaces.c     | 5 +++--
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/dispextern.h b/src/dispextern.h
index 724aad4..6b72e68 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -3559,7 +3559,7 @@ void recompute_basic_faces (struct frame *);
 int face_at_buffer_position (struct window *, ptrdiff_t, ptrdiff_t *,
                              ptrdiff_t, bool, int, enum lface_attribute_index);
 int face_for_overlay_string (struct window *, ptrdiff_t, ptrdiff_t *, 
ptrdiff_t,
-                             bool, Lisp_Object);
+                             bool, Lisp_Object, enum lface_attribute_index);
 int face_at_string_position (struct window *, Lisp_Object, ptrdiff_t, 
ptrdiff_t,
                              ptrdiff_t *, enum face_id, bool,
                              enum lface_attribute_index);
diff --git a/src/xdisp.c b/src/xdisp.c
index a819f0a..37fe380 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -4322,7 +4322,7 @@ face_at_pos (const struct it *it, enum 
lface_attribute_index attr_filter)
                                       (IT_CHARPOS (*it)
                                        + TEXT_PROP_DISTANCE_LIMIT),
                                       false,
-                                      from_overlay);
+                                      from_overlay, attr_filter);
        }
       else
        {
diff --git a/src/xfaces.c b/src/xfaces.c
index 711ec48..12eb7de 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -6330,7 +6330,8 @@ face_at_buffer_position (struct window *w, ptrdiff_t pos,
 int
 face_for_overlay_string (struct window *w, ptrdiff_t pos,
                         ptrdiff_t *endptr, ptrdiff_t limit,
-                        bool mouse, Lisp_Object overlay)
+                        bool mouse, Lisp_Object overlay,
+                        enum lface_attribute_index attr_filter)
 {
   struct frame *f = XFRAME (w->frame);
   Lisp_Object attrs[LFACE_VECTOR_SIZE];
@@ -6369,7 +6370,7 @@ face_for_overlay_string (struct window *w, ptrdiff_t pos,
 
   /* Merge in attributes specified via text properties.  */
   if (!NILP (prop))
-    merge_face_ref (w, f, prop, attrs, true, NULL, 0);
+    merge_face_ref (w, f, prop, attrs, true, NULL, attr_filter);
 
   *endptr = endpos;