X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/06d8ace51597cd41e110560a56a1abeb6cce23d6..ac0215a325f4226b73fd650318349395a6d88835:/lisp/loadhist.el

diff --git a/lisp/loadhist.el b/lisp/loadhist.el
index 763d8c38eb..620344734b 100644
--- a/lisp/loadhist.el
+++ b/lisp/loadhist.el
@@ -1,7 +1,6 @@
 ;;; loadhist.el --- lisp functions for working with feature groups
 
-;; Copyright (C) 1995, 1998, 2000, 2001, 2002, 2003, 2004,
-;;   2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+;; Copyright (C) 1995, 1998, 2000-2013 Free Software Foundation, Inc.
 
 ;; Author: Eric S. Raymond <esr@snark.thyrsus.com>
 ;; Maintainer: FSF
@@ -30,8 +29,6 @@
 
 ;;; Code:
 
-(eval-when-compile (require 'cl))
-
 (defun feature-symbols (feature)
   "Return the file and list of definitions associated with FEATURE.
 The value is actually the element of `load-history'
@@ -116,33 +113,54 @@ from a file."
 (defvaralias 'loadhist-hook-functions 'unload-feature-special-hooks)
 (defvar unload-feature-special-hooks
   '(after-change-functions after-insert-file-functions
-    after-make-frame-functions auto-fill-function before-change-functions
+    after-make-frame-functions auto-coding-functions
+    auto-fill-function before-change-functions
     blink-paren-function buffer-access-fontify-functions
-    choose-completion-string-functions command-line-functions
-    comment-indent-function compilation-finish-functions delete-frame-functions
-    disabled-command-function find-file-not-found-functions
-    font-lock-beginning-of-syntax-function font-lock-fontify-buffer-function
-    font-lock-fontify-region-function font-lock-mark-block-function
-    font-lock-syntactic-face-function font-lock-unfontify-buffer-function
-    font-lock-unfontify-region-function kill-buffer-query-functions
-    kill-emacs-query-functions lisp-indent-function mouse-position-function
+    choose-completion-string-functions
+    comint-output-filter-functions command-line-functions
+    comment-indent-function compilation-finish-functions
+    delete-frame-functions disabled-command-function
+    fill-nobreak-predicate find-directory-functions
+    find-file-not-found-functions
+    font-lock-beginning-of-syntax-function
+    font-lock-fontify-buffer-function
+    font-lock-fontify-region-function
+    font-lock-mark-block-function
+    font-lock-syntactic-face-function
+    font-lock-unfontify-buffer-function
+    font-lock-unfontify-region-function
+    kill-buffer-query-functions kill-emacs-query-functions
+    lisp-indent-function mouse-position-function
     redisplay-end-trigger-functions suspend-tty-functions
     temp-buffer-show-function window-scroll-functions
-    window-size-change-functions write-contents-functions write-file-functions
-    write-region-annotate-functions)
+    window-size-change-functions write-contents-functions
+    write-file-functions write-region-annotate-functions)
   "A list of special hooks from Info node `(elisp)Standard Hooks'.
 
 These are symbols with hooklike values whose names don't end in
 `-hook' or `-hooks', from which `unload-feature' should try to remove
 pertinent symbols.")
 
+(define-obsolete-variable-alias 'unload-hook-features-list
+    'unload-function-defs-list "22.2")
 (defvar unload-function-defs-list nil
-  "List of defintions in the Lisp library being unloaded.
+  "List of definitions in the Lisp library being unloaded.
 
 This is meant to be used by `FEATURE-unload-function'; see the
 documentation of `unload-feature' for details.")
-(define-obsolete-variable-alias 'unload-hook-features-list
-    'unload-function-defs-list "22.2")
+
+(defun unload--set-major-mode ()
+  (save-current-buffer
+    (dolist (buffer (buffer-list))
+      (set-buffer buffer)
+      (let ((proposed major-mode))
+        ;; Look for a predecessor mode not defined in the feature we're processing
+        (while (and proposed (rassq proposed unload-function-defs-list))
+          (setq proposed (get proposed 'derived-mode-parent)))
+        (unless (eq proposed major-mode)
+          ;; Two cases: either proposed is nil, and we want to switch to fundamental
+          ;; mode, or proposed is not nil and not major-mode, and so we use it.
+          (funcall (or proposed 'fundamental-mode)))))))
 
 ;;;###autoload
 (defun unload-feature (feature &optional force)
@@ -223,6 +241,10 @@ something strange, such as redefining an Emacs function."
 		     (not (get (cdr y) 'autoload)))
 	    (setq auto-mode-alist
 		  (rassq-delete-all (cdr y) auto-mode-alist)))))
+
+      ;; Change major mode in all buffers using one defined in the feature being unloaded.
+      (unload--set-major-mode)
+
       (when (fboundp 'elp-restore-function) ; remove ELP stuff first
 	(dolist (elt unload-function-defs-list)
 	  (when (symbolp elt)
@@ -230,11 +252,11 @@ something strange, such as redefining an Emacs function."
 
       (dolist (x unload-function-defs-list)
 	(if (consp x)
-	    (case (car x)
+	    (pcase (car x)
 	      ;; Remove any feature names that this file provided.
-	      (provide
+	      (`provide
 	       (setq features (delq (cdr x) features)))
-	      ((defun autoload)
+	      ((or `defun `autoload)
 	       (let ((fun (cdr x)))
 		 (when (fboundp fun)
 		   (when (fboundp 'ad-unadvise)
@@ -246,9 +268,9 @@ something strange, such as redefining an Emacs function."
 	      ;; (t . SYMBOL) comes before (defun . SYMBOL)
 	      ;; and says we should restore SYMBOL's autoload
 	      ;; when we undefine it.
-	      ((t) (setq restore-autoload (cdr x)))
-	      ((require defface) nil)
-	      (t (message "Unexpected element %s in load-history" x)))
+	      (`t (setq restore-autoload (cdr x)))
+	      ((or `require `defface) nil)
+	      (_ (message "Unexpected element %s in load-history" x)))
 	  ;; Kill local values as much as possible.
 	  (dolist (buf (buffer-list))
 	    (with-current-buffer buf