* lisp/emacs-lisp/advice.el (ad-preactivate-advice): Adjust the cleanup to

the use of nadvice.el.
* lisp/emacs-lisp/nadvice.el (advice--tweak): Make it possible for `tweak'
to return an explicit nil.
(advice--remove-function): Change accordingly.
* test/automated/advice-tests.el: Split up.  Add advice-test-preactivate.

2 files changed, 11 insertions, 13 deletions

diff --git a/lisp/emacs-lisp/advice.el b/lisp/emacs-lisp/advice.el
index 07340f06a13..3d03e894534 100644
--- a/lisp/emacs-lisp/advice.el
+++ b/lisp/emacs-lisp/advice.el
@@ -2866,10 +2866,8 @@ advised definition from scratch."
 
 (defun ad-preactivate-advice (function advice class position)
   "Preactivate FUNCTION and returns the constructed cache."
-  (let* ((function-defined-p (fboundp function))
-	 (old-definition
-	  (if function-defined-p
-	      (symbol-function function)))
+  (let* ((advicefunname (ad-get-advice-info-field function 'advicefunname))
+         (old-advice (symbol-function advicefunname))
 	 (old-advice-info (ad-copy-advice-info function))
 	 (ad-advised-functions ad-advised-functions))
     (unwind-protect
@@ -2883,10 +2881,9 @@ advised definition from scratch."
 	      (list (ad-get-cache-definition function)
 		    (ad-get-cache-id function))))
       (ad-set-advice-info function old-advice-info)
-      ;; Don't `fset' function to nil if it was previously unbound:
-      (if function-defined-p
-	  (fset function old-definition)
-	(fmakunbound function)))))
+      (advice-remove function advicefunname)
+      (fset advicefunname old-advice)
+      (if old-advice (advice-add function :around advicefunname)))))
 
 
 ;; @@ Activation and definition handling:
diff --git a/lisp/emacs-lisp/nadvice.el b/lisp/emacs-lisp/nadvice.el
index 1715763d482..b0711fed26c 100644
--- a/lisp/emacs-lisp/nadvice.el
+++ b/lisp/emacs-lisp/nadvice.el
@@ -173,20 +173,21 @@ WHERE is a symbol to select an entry in `advice--where-alist'."
     (let ((first (advice--car flist))
           (rest (advice--cdr flist))
           (props (advice--props flist)))
-      (or (funcall tweaker first rest props)
+      (let ((val (funcall tweaker first rest props)))
+        (if val (car val)
           (let ((nrest (advice--tweak rest tweaker)))
             (if (eq rest nrest) flist
               (advice--make-1 (aref flist 1) (aref flist 3)
-                              first nrest props)))))))
+                              first nrest props))))))))
 
 ;;;###autoload
 (defun advice--remove-function (flist function)
   (advice--tweak flist
                  (lambda (first rest props)
-                   (if (or (not first)
-                           (equal function first)
+                   (cond ((not first) rest)
+                         ((or (equal function first)
                            (equal function (cdr (assq 'name props))))
-                       rest))))
+                          (list rest))))))
 
 (defvar advice--buffer-local-function-sample nil)