Drop use of unsafep for checking Custom themes; bugfixes.

* lisp/custom.el (load-theme): Define return value.  Drop use of
unsafep; call custom-theme-load-confirm for non-known-safe themes.
(custom-theme-load-confirm): Scroll in the correct window.
(custom-enabled-themes): Add custom-safe-themes to :set-after.

* lisp/cus-theme.el (custom-theme-checkbox-toggle): Don't activate the
checkbox if load-theme fails.

1 files changed, 29 insertions, 40 deletions

diff --git a/lisp/custom.el b/lisp/custom.el
index e31948ec4b4..e41e7c7bdf8 100644
--- a/lisp/custom.el
+++ b/lisp/custom.el
@@ -1116,16 +1116,15 @@ Emacs theme directory (a directory named \"themes\" in
   :risky t
   :version "24.1")
 
-(defvar safe-functions) ; From unsafep.el
-
 (defun load-theme (theme &optional no-enable)
-  "Load a theme's settings from its file.
-Normally, this also enables the theme; use `disable-theme' to
-disable it.  If optional arg NO-ENABLE is non-nil, don't enable
-the theme.
+  "Load Custom theme named THEME from its file.
+Normally, this also enables THEME.  If optional arg NO-ENABLE is
+non-nil, load THEME but don't enable it.
+
+The theme file is named THEME-theme.el, in one of the directories
+specified by `custom-theme-load-path'.
 
-A theme file is named THEME-theme.el, where THEME is the theme name,
-in one of the directories specified by `custom-theme-load-path'."
+Return t if THEME was successfully loaded, nil otherwise."
   (interactive
    (list
     (intern (completing-read "Load custom theme: "
@@ -1148,30 +1147,16 @@ in one of the directories specified by `custom-theme-load-path'."
     (with-temp-buffer
       (insert-file-contents fn)
       (setq hash (sha1 (current-buffer)))
-      ;; Check file safety.
+      ;; Check file safety with `custom-safe-themes', prompting the
+      ;; user if necessary.
       (when (or (and (memq 'default custom-safe-themes)
                      (equal (file-name-directory fn)
                             (expand-file-name "themes/" data-directory)))
                 (member hash custom-safe-themes)
-                ;; If the theme is not in `custom-safe-themes', check
-                ;; it with unsafep.
-                (progn
-                  (require 'unsafep)
-                  (let ((safe-functions
-                         (append '(provide-theme deftheme
-                                   custom-theme-set-variables
-                                   custom-theme-set-faces)
-                                 safe-functions))
-                        unsafep form)
-                    (while (and (setq form (condition-case nil
-                                               (let ((read-circle nil))
-                                                 (read (current-buffer)))
-                                             (end-of-file nil)))
-                                (null (setq unsafep (unsafep form)))))
-                    (or (null unsafep)
-                        (custom-theme-load-confirm hash)))))
+                (custom-theme-load-confirm hash))
         (let ((custom--inhibit-theme-enable no-enable))
-          (eval-buffer))))))
+          (eval-buffer)
+          t)))))
 
 (defun custom-theme-load-confirm (hash)
   "Query the user about loading a Custom theme that may not be safe.
@@ -1180,32 +1165,35 @@ query also about adding HASH to `custom-safe-themes'."
   (if noninteractive
       nil
     (let ((exit-chars '(?y ?n ?\s))
-          prompt char)
+          window prompt char)
       (save-window-excursion
         (rename-buffer "*Custom Theme*" t)
         (emacs-lisp-mode)
-        (display-buffer (current-buffer))
+        (setq window (display-buffer (current-buffer)))
         (setq prompt
-              (format "This theme is not guaranteed to be safe.  Really load? %s"
-                      (if (< (line-number-at-pos (point-max))
-                             (window-body-height))
-                          "(y or n) "
+              (format "Loading a theme can run Lisp code.  Really load?%s"
+                      (if (and window
+                               (< (line-number-at-pos (point-max))
+                                  (window-body-height)))
+                          " (y or n) "
                         (push ?\C-v exit-chars)
-                        "Type y or n, or C-v to scroll: ")))
+                        "\nType y or n, or C-v to scroll: ")))
         (goto-char (point-min))
         (while (null char)
           (setq char (read-char-choice prompt exit-chars))
           (when (eq char ?\C-v)
-            (condition-case nil
-                (scroll-up)
-              (error (goto-char (point-min))))
+            (if window
+                (with-selected-window window
+                  (condition-case nil
+                      (scroll-up)
+                    (error (goto-char (point-min))))))
             (setq char nil)))
         (when (memq char '(?\s ?y))
-          (push hash custom-safe-themes)
           ;; Offer to save to `custom-safe-themes'.
           (and (or custom-file user-init-file)
-               (y-or-n-p "Treat this theme as safe for future loads? ")
+               (y-or-n-p "Treat this theme as safe in future sessions? ")
                (let ((coding-system-for-read nil))
+                 (push hash custom-safe-themes)
                  (customize-save-variable 'custom-safe-themes
                                           custom-safe-themes)))
           t)))))
@@ -1285,7 +1273,8 @@ This does not include the `user' theme, which is set by Customize,
 and always takes precedence over other Custom Themes."
   :group 'customize
   :type  '(repeat symbol)
-  :set-after '(custom-theme-directory custom-theme-load-path)
+  :set-after '(custom-theme-directory custom-theme-load-path
+                                      custom-safe-themes)
   :risky t
   :set (lambda (symbol themes)
          ;; Avoid an infinite loop when custom-enabled-themes is