Re: face-remapping patch

[Miles Bader <miles@gnu.org>]

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Here's a new patch addressing your comments.

-Miles

-- 
Custard, n. A vile concoction produced by a malevolent conspiracy of the hen,
the cow, and the cook.

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orig = emacs@sv.gnu.org/emacs--devo--0--patch-1183
mod = emacs@sv.gnu.org/emacs--devo--0--patch-1183

A  src/ChangeLog.face-remap
M  src/xfaces.c
M  src/dispextern.h
M  src/fontset.c
M  src/xdisp.c
M  doc/lispref/display.texi

--- orig/doc/lispref/display.texi
+++ mod/doc/lispref/display.texi
@@ -2365,6 +2365,58 @@
   When multiple overlays cover one character, an overlay with higher
 priority overrides those with lower priority.  @xref{Overlays}.
 
+@defvar face-remapping-alist
+@tindex face-remapping-alist
+  This variable is used for buffer-local changes in the appearance of
+a face, for instance making the @code{default} face a variable-pitch
+face in a particular buffer.
+
+  Its value should be an alist, whose elements have the form
+@code{(@var{face} @var{remapping}@dots{})}; when the text specifies
+face @var{face}, Emacs redisplay uses @var{remapping}@dots{} instead.
+@var{remapping}@dots{} may be any face specification suitable for a
+@code{face} text property, usually a face name, but also perhaps a
+property list of face attribute/value pairs; @xref{Special
+Properties}.
+
+Two points bear emphasizing:
+
+@enumerate
+@item
+The new definition @var{remapping}@dots{} is the complete
+specification of how to display @var{face}---it entirely replaces,
+rather than augmenting or modifying, the normal definition of that
+face.
+
+@item
+If @var{remapping}@dots{} recursively references the same face name
+@var{face}, either directly remapping entry, or via the
+@code{:inherit} attribute of some other face in
+@var{remapping}@dots{}, then that reference uses normal frame-wide
+definition of @var{face} instead of the `remapped' definition.
+
+For instance, if the @code{mode-line} face is remapped using this
+entry in @code{face-remapping-alist}:
+@example
+(mode-line italic mode-line)
+@end example
+Then the new definition of the @code{mode-line} face inherits from the
+@code{italic} face, and the @emph{normal} (non-remapped) definition of
+@code{mode-line} face.
+@end enumerate
+
+  A typical use of the @code{face-remapping-alist} is to change a
+buffer's @code{default} face; for example, the following changes a
+buffer's @code{default} face to use the @code{variable-pitch} face,
+with the height doubled:
+
+@example
+(set (make-local-variable 'face-remapping-alist)
+     '((default variable-pitch :height 2.0)))
+@end example
+
+@end defvar
+
 @node Font Selection
 @subsection Font Selection
 


--- orig/src/dispextern.h
+++ mod/src/dispextern.h
@@ -2852,6 +2852,7 @@
 int lookup_face P_ ((struct frame *, Lisp_Object *));
 int lookup_non_ascii_face P_ ((struct frame *, int, struct face *));
 int lookup_named_face P_ ((struct frame *, Lisp_Object, int));
+int lookup_basic_face P_ ((struct frame *, int));
 int smaller_face P_ ((struct frame *, int, int));
 int face_with_height P_ ((struct frame *, int, int));
 int lookup_derived_face P_ ((struct frame *, Lisp_Object, int, int));
@@ -2880,6 +2881,8 @@
 extern Lisp_Object split_font_name_into_vector P_ ((Lisp_Object));
 extern Lisp_Object build_font_name_from_vector P_ ((Lisp_Object));
 
+extern Lisp_Object Vface_remapping_alist;
+
 /* Defined in xfns.c  */
 
 #ifdef HAVE_X_WINDOWS


--- orig/src/fontset.c
+++ mod/src/fontset.c
@@ -1727,7 +1727,7 @@
       CHECK_CHARACTER (ch);
       c = XINT (ch);
       f = XFRAME (selected_frame);
-      face_id = DEFAULT_FACE_ID;
+      face_id = lookup_basic_face (f, DEFAULT_FACE_ID);
       pos = -1;
       cs_id = -1;
     }


--- orig/src/xdisp.c
+++ mod/src/xdisp.c
@@ -2493,6 +2493,7 @@
      enum face_id base_face_id;
 {
   int highlight_region_p;
+  enum face_id remapped_base_face_id = base_face_id;
 
   /* Some precondition checks.  */
   xassert (w != NULL && it != NULL);
@@ -2509,6 +2510,10 @@
       free_all_realized_faces (Qnil);
     }
 
+  /* Perhaps remap BASE_FACE_ID to a user-specified alternative.  */
+  if (! NILP (Vface_remapping_alist))
+    remapped_base_face_id = lookup_basic_face (XFRAME (w->frame), base_face_id);
+
   /* Use one of the mode line rows of W's desired matrix if
      appropriate.  */
   if (row == NULL)
@@ -2524,7 +2529,7 @@
   bzero (it, sizeof *it);
   it->current.overlay_string_index = -1;
   it->current.dpvec_index = -1;
-  it->base_face_id = base_face_id;
+  it->base_face_id = remapped_base_face_id;
   it->string = Qnil;
   IT_STRING_CHARPOS (*it) = IT_STRING_BYTEPOS (*it) = -1;
 
@@ -2709,11 +2714,11 @@
     {
       struct face *face;
 
-      it->face_id = base_face_id;
+      it->face_id = remapped_base_face_id;
 
       /* If we have a boxed mode line, make the first character appear
 	 with a left box line.  */
-      face = FACE_FROM_ID (it->f, base_face_id);
+      face = FACE_FROM_ID (it->f, remapped_base_face_id);
       if (face->box != FACE_NO_BOX)
 	it->start_of_box_run_p = 1;
     }
@@ -4079,7 +4084,8 @@
 	      /* Value is a multiple of the canonical char height.  */
 	      struct face *face;
 
-	      face = FACE_FROM_ID (it->f, DEFAULT_FACE_ID);
+	      face = FACE_FROM_ID (it->f,
+				   lookup_basic_face (it->f, DEFAULT_FACE_ID));
 	      new_height = (XFLOATINT (it->font_height)
 			    * XINT (face->lface[LFACE_HEIGHT_INDEX]));
 	    }
@@ -4189,7 +4195,7 @@
 	  || EQ (XCAR (spec), Qright_fringe))
       && CONSP (XCDR (spec)))
     {
-      int face_id = DEFAULT_FACE_ID;
+      int face_id = lookup_basic_face (it->f, DEFAULT_FACE_ID);
       int fringe_bitmap;
 
       if (!FRAME_WINDOW_P (it->f))


--- orig/src/xfaces.c
+++ mod/src/xfaces.c
@@ -422,6 +422,23 @@
 
 Lisp_Object Vface_new_frame_defaults;
 
+/* Alist of face remappings.  Each element is of the form:
+   (FACE REPLACEMENT...) which causes display of the face FACE to use
+   REPLACEMENT... instead.  REPLACEMENT... is interpreted the same way
+   the value of a `face' text property is: it may be (1) A face name,
+   (2) A list of face names, (3) A property-list of face attribute/value
+   pairs, or (4) A list of face names intermixed with lists containing
+   face attribute/value pairs.
+
+   Multiple entries in REPLACEMENT... are merged together to form the final
+   result, with faces or attributes earlier in the list taking precedence
+   over those that are later.
+
+   Face-name remapping cycles are suppressed; recursive references use
+   the underlying face instead of the remapped face.  */
+
+Lisp_Object Vface_remapping_alist;
+
 /* The next ID to assign to Lisp faces.  */
 
 static int next_lface_id;
@@ -493,7 +510,8 @@
 static Lisp_Object resolve_face_name P_ ((Lisp_Object, int));
 static int may_use_scalable_font_p P_ ((const char *));
 static void set_font_frame_param P_ ((Lisp_Object, Lisp_Object));
-static int get_lface_attributes P_ ((struct frame *, Lisp_Object, Lisp_Object *, int));
+static int get_lface_attributes P_ ((struct frame *, Lisp_Object, Lisp_Object *,
+				     int, struct named_merge_point *));
 static int load_pixmap P_ ((struct frame *, Lisp_Object, unsigned *, unsigned *));
 static unsigned char *xstrlwr P_ ((unsigned char *));
 static struct frame *frame_or_selected_frame P_ ((Lisp_Object, int));
@@ -2058,6 +2076,12 @@
 \f
 /* Face-merge cycle checking.  */
 
+enum named_merge_point_kind
+{
+  NAMED_MERGE_POINT_NORMAL,
+  NAMED_MERGE_POINT_REMAP
+};
+
 /* A `named merge point' is simply a point during face-merging where we
    look up a face by name.  We keep a stack of which named lookups we're
    currently processing so that we can easily detect cycles, using a
@@ -2067,27 +2091,40 @@
 struct named_merge_point
 {
   Lisp_Object face_name;
+  enum named_merge_point_kind named_merge_point_kind;
   struct named_merge_point *prev;
 };
 
 
 /* If a face merging cycle is detected for FACE_NAME, return 0,
    otherwise add NEW_NAMED_MERGE_POINT, which is initialized using
-   FACE_NAME, as the head of the linked list pointed to by
-   NAMED_MERGE_POINTS, and return 1.  */
+   FACE_NAME and NAMED_MERGE_POINT_KIND, as the head of the linked list
+   pointed to by NAMED_MERGE_POINTS, and return 1.  */
 
 static INLINE int
 push_named_merge_point (struct named_merge_point *new_named_merge_point,
 			Lisp_Object face_name,
+			enum named_merge_point_kind named_merge_point_kind,
 			struct named_merge_point **named_merge_points)
 {
   struct named_merge_point *prev;
 
   for (prev = *named_merge_points; prev; prev = prev->prev)
     if (EQ (face_name, prev->face_name))
-      return 0;
+      {
+	if (prev->named_merge_point_kind == named_merge_point_kind)
+	  /* A cycle, so fail.  */
+	  return 0;
+	else if (prev->named_merge_point_kind == NAMED_MERGE_POINT_REMAP)
+	  /* A remap `hides ' any previous normal merge points
+	     (because the remap means that it's actually different face),
+	     so as we know the current merge point must be normal, we
+	     can just assume it's OK.  */
+	  break;
+      }
 
   new_named_merge_point->face_name = face_name;
+  new_named_merge_point->named_merge_point_kind = named_merge_point_kind;
   new_named_merge_point->prev = *named_merge_points;
 
   *named_merge_points = new_named_merge_point;
@@ -2165,22 +2202,17 @@
 /* Return the face definition of FACE_NAME on frame F.  F null means
    return the definition for new frames.  FACE_NAME may be a string or
    a symbol (apparently Emacs 20.2 allowed strings as face names in
-   face text properties; Ediff uses that).  If FACE_NAME is an alias
-   for another face, return that face's definition.  If SIGNAL_P is
-   non-zero, signal an error if FACE_NAME is not a valid face name.
-   If SIGNAL_P is zero, value is nil if FACE_NAME is not a valid face
-   name.  */
-
+   face text properties; Ediff uses that).  If SIGNAL_P is non-zero,
+   signal an error if FACE_NAME is not a valid face name.  If SIGNAL_P
+   is zero, value is nil if FACE_NAME is not a valid face name.  */
 static INLINE Lisp_Object
-lface_from_face_name (f, face_name, signal_p)
+lface_from_face_name_no_resolve (f, face_name, signal_p)
      struct frame *f;
      Lisp_Object face_name;
      int signal_p;
 {
   Lisp_Object lface;
 
-  face_name = resolve_face_name (face_name, signal_p);
-
   if (f)
     lface = assq_no_quit (face_name, f->face_alist);
   else
@@ -2192,9 +2224,28 @@
     signal_error ("Invalid face", face_name);
 
   check_lface (lface);
+
   return lface;
 }
 
+/* Return the face definition of FACE_NAME on frame F.  F null means
+   return the definition for new frames.  FACE_NAME may be a string or
+   a symbol (apparently Emacs 20.2 allowed strings as face names in
+   face text properties; Ediff uses that).  If FACE_NAME is an alias
+   for another face, return that face's definition.  If SIGNAL_P is
+   non-zero, signal an error if FACE_NAME is not a valid face name.
+   If SIGNAL_P is zero, value is nil if FACE_NAME is not a valid face
+   name.  */
+static INLINE Lisp_Object
+lface_from_face_name (f, face_name, signal_p)
+     struct frame *f;
+     Lisp_Object face_name;
+     int signal_p;
+{
+  face_name = resolve_face_name (face_name, signal_p);
+  return lface_from_face_name_no_resolve (f, face_name, signal_p);
+}
+
 
 /* Get face attributes of face FACE_NAME from frame-local faces on
    frame F.  Store the resulting attributes in ATTRS which must point
@@ -2203,26 +2254,65 @@
    Otherwise, value is zero if FACE_NAME is not a face.  */
 
 static INLINE int
-get_lface_attributes (f, face_name, attrs, signal_p)
+get_lface_attributes_no_remap (f, face_name, attrs, signal_p)
      struct frame *f;
      Lisp_Object face_name;
      Lisp_Object *attrs;
      int signal_p;
 {
   Lisp_Object lface;
-  int success_p;
 
-  lface = lface_from_face_name (f, face_name, signal_p);
-  if (!NILP (lface))
+  lface = lface_from_face_name_no_resolve (f, face_name, signal_p);
+
+  if (! NILP (lface))
+    bcopy (XVECTOR (lface)->contents, attrs,
+	   LFACE_VECTOR_SIZE * sizeof *attrs);
+
+  return !NILP (lface);
+}
+
+/* Get face attributes of face FACE_NAME from frame-local faces on frame
+   F.  Store the resulting attributes in ATTRS which must point to a
+   vector of Lisp_Objects of size LFACE_VECTOR_SIZE.  If FACE_NAME is an
+   alias for another face, use that face's definition.  If SIGNAL_P is
+   non-zero, signal an error if FACE_NAME does not name a face.
+   Otherwise, value is zero if FACE_NAME is not a face.  */
+
+static INLINE int
+get_lface_attributes (f, face_name, attrs, signal_p, named_merge_points)
+     struct frame *f;
+     Lisp_Object face_name;
+     Lisp_Object *attrs;
+     int signal_p;
+     struct named_merge_point *named_merge_points;
+{
+  Lisp_Object face_remapping;
+
+  face_name = resolve_face_name (face_name, signal_p);
+
+  /* See if SYMBOL has been remapped to some other face (usually this
+     is done buffer-locally).  */
+  face_remapping = assq_no_quit (face_name, Vface_remapping_alist);
+  if (CONSP (face_remapping))
     {
-      bcopy (XVECTOR (lface)->contents, attrs,
-	     LFACE_VECTOR_SIZE * sizeof *attrs);
-      success_p = 1;
+      struct named_merge_point named_merge_point;
+
+      if (push_named_merge_point (&named_merge_point,
+				  face_name, NAMED_MERGE_POINT_REMAP,
+				  &named_merge_points))
+	{
+	  int i;
+
+	  for (i = 1; i < LFACE_VECTOR_SIZE; ++i)
+	    attrs[i] = Qunspecified;
+
+	  return merge_face_ref (f, XCDR (face_remapping), attrs,
+				 signal_p, named_merge_points);
+	}
     }
-  else
-    success_p = 0;
 
-  return success_p;
+  /* Default case, no remapping.  */
+  return get_lface_attributes_no_remap (f, face_name, attrs, signal_p);
 }
 
 
@@ -2378,8 +2468,8 @@
    specified attribute of FROM overrides the corresponding attribute of
    TO; relative attributes in FROM are merged with the absolute value in
    TO and replace it.  NAMED_MERGE_POINTS is used internally to detect
-   loops in face inheritance; it should be 0 when called from other
-   places.  */
+   loops in face inheritance/remapping; it should be 0 when called from
+   other places.  */
 
 static INLINE void
 merge_face_vectors (f, from, to, named_merge_points)
@@ -2454,11 +2544,12 @@
   struct named_merge_point named_merge_point;
 
   if (push_named_merge_point (&named_merge_point,
-			      face_name, &named_merge_points))
+			      face_name, NAMED_MERGE_POINT_NORMAL,
+			      &named_merge_points))
     {
       struct gcpro gcpro1;
       Lisp_Object from[LFACE_VECTOR_SIZE];
-      int ok = get_lface_attributes (f, face_name, from, 0);
+      int ok = get_lface_attributes (f, face_name, from, 0, named_merge_points);
 
       if (ok)
 	{
@@ -3436,7 +3527,7 @@
 
       /* Changing the background color might change the background
 	 mode, so that we have to load new defface specs.
-	 Call frame-set-background-mode to do that.  */
+	 Call frame-update-face-colors to do that.  */
       XSETFRAME (frame, f);
       call1 (Qframe_set_background_mode, frame);
 
@@ -4642,7 +4733,7 @@
 	abort ();  /* realize_basic_faces must have set it up  */
     }
 
-  if (!get_lface_attributes (f, symbol, symbol_attrs, signal_p))
+  if (! get_lface_attributes (f, symbol, symbol_attrs, signal_p, 0))
     return -1;
 
   bcopy (default_face->lface, attrs, sizeof attrs);
@@ -4652,6 +4743,58 @@
 }
 
 
+/* Return the display face-id of the basic face who's canonical face-id
+   is FACE_ID.  The return value will usually simply be FACE_ID, unless that
+   basic face has bee remapped via Vface_remapping_alist.  This function is
+   conservative: if something goes wrong, it will simply return FACE_ID
+   rather than signal an error.   */
+
+int
+lookup_basic_face (f, face_id)
+     struct frame *f;
+     int face_id;
+{
+  Lisp_Object name, mapping;
+  int remapped_face_id;
+
+  if (NILP (Vface_remapping_alist))
+    return face_id;		/* Nothing to do.  */
+
+  switch (face_id)
+    {
+    case DEFAULT_FACE_ID:		name = Qdefault;		break;
+    case MODE_LINE_FACE_ID:		name = Qmode_line;		break;
+    case MODE_LINE_INACTIVE_FACE_ID:	name = Qmode_line_inactive;	break;
+    case HEADER_LINE_FACE_ID:		name = Qheader_line;		break;
+    case TOOL_BAR_FACE_ID:		name = Qtool_bar;		break;
+    case FRINGE_FACE_ID:		name = Qfringe;			break;
+    case SCROLL_BAR_FACE_ID:		name = Qscroll_bar;		break;
+    case BORDER_FACE_ID:		name = Qborder;			break;
+    case CURSOR_FACE_ID:		name = Qcursor;			break;
+    case MOUSE_FACE_ID:			name = Qmouse;			break;
+    case MENU_FACE_ID:			name = Qmenu;			break;
+
+    default:
+      abort ();	    /* the caller is supposed to pass us a basic face id */
+    }
+
+  /* Do a quick scan through Vface_remapping_alist, and return immediately
+     if there is no remapping for face NAME.  This is just an optimization
+     for the very common no-remapping case.  */
+  mapping = assq_no_quit (name, Vface_remapping_alist);
+  if (NILP (mapping))
+    return face_id;		/* Give up.  */
+
+  /* If there is a remapping entry, lookup the face using NAME, which will
+     handle the remapping too.  */
+  remapped_face_id = lookup_named_face (f, name, 0);
+  if (remapped_face_id < 0)
+    return face_id;		/* Give up. */
+
+  return remapped_face_id;
+}
+
+
 /* Return the ID of the realized ASCII face of Lisp face with ID
    LFACE_ID on frame F.  Value is -1 if LFACE_ID isn't valid.  */
 
@@ -4784,7 +4927,7 @@
   if (!default_face)
     abort ();
 
-  get_lface_attributes (f, symbol, symbol_attrs, signal_p);
+  get_lface_attributes (f, symbol, symbol_attrs, signal_p, 0);
   bcopy (default_face->lface, attrs, sizeof attrs);
   merge_face_vectors (f, symbol_attrs, attrs, 0);
   return lookup_face (f, attrs);
@@ -5493,7 +5636,7 @@
   struct face *new_face;
 
   /* The default face must exist and be fully specified.  */
-  get_lface_attributes (f, Qdefault, attrs, 1);
+  get_lface_attributes_no_remap (f, Qdefault, attrs, 1);
   check_lface_attrs (attrs);
   xassert (lface_fully_specified_p (attrs));
 
@@ -5506,7 +5649,7 @@
     }
 
   /* Merge SYMBOL's face with the default face.  */
-  get_lface_attributes (f, symbol, symbol_attrs, 1);
+  get_lface_attributes_no_remap (f, symbol, symbol_attrs, 1);
   merge_face_vectors (f, symbol_attrs, attrs, 0);
 
   /* Realize the face.  */
@@ -6063,13 +6206,18 @@
 
   *endptr = endpos;
 
-  default_face = FACE_FROM_ID (f, DEFAULT_FACE_ID);
+
+  /* Perhaps remap BASE_FACE_ID to a user-specified alternative.  */
+  if (NILP (Vface_remapping_alist))
+    default_face = FACE_FROM_ID (f, DEFAULT_FACE_ID);
+  else
+    default_face = FACE_FROM_ID (f, lookup_basic_face (f, DEFAULT_FACE_ID));
 
   /* Optimize common cases where we can use the default face.  */
   if (noverlays == 0
       && NILP (prop)
       && !(pos >= region_beg && pos < region_end))
-    return DEFAULT_FACE_ID;
+    return default_face->id;
 
   /* Begin with attributes from the default face.  */
   bcopy (default_face->lface, attrs, sizeof attrs);
@@ -6668,6 +6816,43 @@
 ignore.  */);
   Vface_ignored_fonts = Qnil;
 
+  DEFVAR_LISP ("face-remapping-alist", &Vface_remapping_alist,
+	       doc: /* Alist of face remappings.
+Each element is of the form:
+
+   (FACE REPLACEMENT...),
+
+which causes display of the face FACE to use REPLACEMENT... instead.
+REPLACEMENT... is interpreted the same way the value of a `face' text
+property is: it may be (1) A face name, (2) A list of face names, (3) A
+property-list of face attribute/value pairs, or (4) A list of face names
+intermixed with lists containing face attribute/value pairs.
+
+Multiple entries in REPLACEMENT... are merged together to form the final
+result, with faces or attributes earlier in the list taking precedence
+over those that are later.
+
+Face-name remapping cycles are suppressed; recursive references use the
+underlying face instead of the remapped face.  So a remapping of the form:
+
+   (FACE EXTRA-FACE... FACE)
+
+or:
+
+   (FACE (FACE-ATTR VAL ...) FACE)
+
+will cause EXTRA-FACE... or (FACE-ATTR VAL ...) to be _merged_ with the
+existing definition of FACE.  Note that for the default face, this isn't
+necessary, as every face inherits from the default face.
+
+Making this variable buffer-local is a good way to allow buffer-specific
+face definitions.  For instance, the mode my-mode could define a face
+`my-mode-default', and then in the mode setup function, do:
+
+   (set (make-local-variable 'face-remapping-alist)
+        '((default my-mode-default)))).  */);
+  Vface_remapping_alist = Qnil;
+
   DEFVAR_LISP ("face-font-rescale-alist", &Vface_font_rescale_alist,
 	       doc: /* Alist of fonts vs the rescaling factors.
 Each element is a cons (FONT-NAME-PATTERN . RESCALE-RATIO), where



* added files

--- /dev/null
+++ mod/src/ChangeLog.face-remap
@@ -0,0 +1,35 @@
+2008-05-29  Miles Bader  <miles@gnu.org>
+
+	* xfaces.c (Vface_remapping_alist): New variable.
+	(syms_of_xfaces): Initialize it.
+	(enum named_merge_point_kind): New type.
+	(struct named_merge_point): Add `named_merge_point_kind' field.
+	(push_named_merge_point): Make cycle detection respect different
+	named-merge-point kinds.
+	(lface_from_face_name_no_resolve): Renamed from `lface_from_face_name'.
+	Remove face-name alias resolution.
+	(lface_from_face_name): New definition using
+	`lface_from_face_name_no_resolve'.
+	(get_lface_attributes_no_remap): Renamed from `get_lface_attributes'.
+	Call lface_from_face_name_no_resolve instead of lface_from_face_name.
+	(get_lface_attributes): New definition that layers face-remapping on
+	top of get_lface_attributes_no_remap.  New arg `named_merge_points'.
+	(lookup_basic_face): New function.
+	(lookup_derived_face): Pass new last arg to `get_lface_attributes'.
+	(realize_named_face): Call `get_lface_attributes_no_remap' instead of
+	`get_lface_attributes'.
+	(face_at_buffer_position): Use `lookup_basic_face' to lookup
+	DEFAULT_FACE_ID if necessary.  When optimizing the default-face case,
+	return default_face's face-id instead of the constant DEFAULT_FACE_ID.
+
+	* xdisp.c (init_iterator): Pass base_face_id through
+	`lookup_basic_face' when we actually use it as a face-id.
+	(handle_single_display_prop): Use `lookup_basic_face' to lookup
+	DEFAULT_FACE_ID.
+
+	* fontset.c (Finternal_char_font): Use `lookup_basic_face' to
+	lookup the initial face-id.
+
+	* dispextern.h (lookup_basic_face, Vface_remapping_alist): New decls.
+
+;; arch-tag: aded4c61-a649-4b57-9c93-5408933a7b40