Re: C-M-x on defface doesn't always work

[Juri Linkov]

> C-M-x on a `defface' form doesn't work for resetting a face if the
> user has set the face through custom. The face spec is not used; in
> custom-declare-face:
>
>      ;; If the user has already created the face, respect that.
>      (let ((value (or (get face 'saved-face) spec)))

I think a good solution here is to reset `saved-face' property to nil
before evaluating the defface form, and to restore its original value
afterwards.  And also to set `customized-face' to the new specification.

This requires modification of the function `face-user-default-spec' to
try getting `customized-face' prior to trying `saved-face'.  This change
in `face-user-default-spec' also fixes one bug where the saved face was
merged with customized non-saved attributes of the same face.
The workflow for reproducing the bug is the following:

1. Customize the foreground color of some face and save it
   ([Save for Future Sessions]).
2. Reset (uncheck) the foreground attribute, set some background color,
   and set the face without saving it ([Set for Current Session]).
3. Create new frame.

Now in a new frame this face appears as merged with customized non-saved
background and saved foreground.  The patch makes such face having
only customized non-saved background.

Index: lisp/emacs-lisp/lisp-mode.el
===================================================================
RCS file: /cvsroot/emacs/emacs/lisp/emacs-lisp/lisp-mode.el,v
retrieving revision 1.176
diff -u -r1.176 lisp-mode.el
--- lisp/emacs-lisp/lisp-mode.el        7 Jun 2005 10:51:36 -0000       1.176
+++ lisp/emacs-lisp/lisp-mode.el        19 Jun 2005 11:19:33 -0000
@@ -617,10 +617,15 @@
        ;; `defface' is macroexpanded to `custom-declare-face'.
        ((eq (car form) 'custom-declare-face)
         ;; Reset the face.
-        (put (eval (nth 1 form)) 'face-defface-spec nil)
         (setq face-new-frame-defaults
               (assq-delete-all (eval (nth 1 form)) face-new-frame-defaults))
-        form)
+        (put (eval (nth 1 form)) 'face-defface-spec nil)
+        (prog1 `(prog1 ,form
+                  (put ',(eval (nth 1 form)) 'saved-face
+                       ',(get (eval (nth 1 form)) 'saved-face))
+                  (put ',(eval (nth 1 form)) 'customized-face
+                       ',(eval (nth 2 form))))
+          (put (eval (nth 1 form)) 'saved-face nil)))
        ((eq (car form) 'progn)
         (cons 'progn (mapcar 'eval-defun-1 (cdr form))))
        (t form)))

Index: lisp/emacs-lisp/edebug.el
===================================================================
RCS file: /cvsroot/emacs/emacs/lisp/emacs-lisp/edebug.el,v
retrieving revision 3.75
diff -u -r3.75 edebug.el
--- lisp/emacs-lisp/edebug.el   17 Jun 2005 14:32:46 -0000      3.75
+++ lisp/emacs-lisp/edebug.el   19 Jun 2005 11:21:18 -0000
@@ -511,9 +511,15 @@
           (set-default (nth 1 form) (eval (nth 2 form))))
           ((eq (car form) 'defface)
            ;; Reset the face.
-           (put (nth 1 form) 'face-defface-spec nil)
            (setq face-new-frame-defaults
-                 (assq-delete-all (nth 1 form) face-new-frame-defaults))))
+                 (assq-delete-all (nth 1 form) face-new-frame-defaults))
+           (put (nth 1 form) 'face-defface-spec nil)
+          (setq form (prog1 `(prog1 ,form
+                               (put ',(nth 1 form) 'saved-face
+                                    ',(get (nth 1 form) 'saved-face))
+                               (put ',(nth 1 form) 'customized-face
+                                    ',(nth 2 form)))
+                       (put (nth 1 form) 'saved-face nil)))))
     (setq edebug-result (eval form))
     (if (not edebugging)
        (princ edebug-result)

Index: lisp/faces.el
===================================================================
RCS file: /cvsroot/emacs/emacs/lisp/faces.el,v
retrieving revision 1.318
diff -u -r1.318 faces.el
--- lisp/faces.el       17 Jun 2005 14:30:55 -0000      1.318
+++ lisp/faces.el       19 Jun 2005 11:19:15 -0000
@@ -1477,7 +1477,8 @@
 (defsubst face-user-default-spec (face)
   "Return the user's customized face-spec for FACE, or the default if none.
 If there is neither a user setting nor a default for FACE, return nil."
-  (or (get face 'saved-face)
+  (or (get face 'customized-face)
+      (get face 'saved-face)
       (face-default-spec face)))
 
 

-- 
Juri Linkov
http://www.jurta.org/emacs/