Merge from emacs-24; up to 2013-01-03T02:31:36Z!rgm@gnu.org

[gnu-emacs] / lisp / emacs-lisp / nadvice.el

diff --git a/lisp/emacs-lisp/nadvice.el b/lisp/emacs-lisp/nadvice.el
index 1715763d48224c9d46c0d3f0d3defa46d3bc891b..576e72088e9760390bc30d043e1b48b07de82e64 100644 (file)
--- a/lisp/emacs-lisp/nadvice.el
+++ b/lisp/emacs-lisp/nadvice.el
@@ -23,7 +23,7 @@
 
 ;; This package lets you add behavior (which we call "piece of advice") to
 ;; existing functions, like the old `advice.el' package, but with much fewer
 
 ;; This package lets you add behavior (which we call "piece of advice") to
 ;; existing functions, like the old `advice.el' package, but with much fewer

-;; bells ans whistles.  It comes in 2 parts:
+;; bells and whistles.  It comes in 2 parts:

 ;;
 ;; - The first part lets you add/remove functions, similarly to
 ;;   add/remove-hook, from any "place" (i.e. as accepted by `setf') that
 ;;
 ;; - The first part lets you add/remove functions, similarly to
 ;;   add/remove-hook, from any "place" (i.e. as accepted by `setf') that


@@ -41,10 +41,13 @@
   '((:around "\300\301\302\003#\207" 5)
     (:before "\300\301\002\"\210\300\302\002\"\207" 4)
     (:after "\300\302\002\"\300\301\003\"\210\207" 5)
   '((:around "\300\301\302\003#\207" 5)
     (:before "\300\301\002\"\210\300\302\002\"\207" 4)
     (:after "\300\302\002\"\300\301\003\"\210\207" 5)

+    (:override "\300\301\ 2\"\207" 4)

     (:after-until "\300\302\002\"\206\013\000\300\301\002\"\207" 4)
     (:after-while "\300\302\002\"\205\013\000\300\301\002\"\207" 4)
     (:before-until "\300\301\002\"\206\013\000\300\302\002\"\207" 4)
     (:after-until "\300\302\002\"\206\013\000\300\301\002\"\207" 4)
     (:after-while "\300\302\002\"\205\013\000\300\301\002\"\207" 4)
     (:before-until "\300\301\002\"\206\013\000\300\302\002\"\207" 4)

-    (:before-while "\300\301\002\"\205\013\000\300\302\002\"\207" 4))
+    (:before-while "\300\301\002\"\205\013\000\300\302\002\"\207" 4)
+    (:filter-args "\300\302\301\ 3!\"\207" 5)
+    (:filter-return "\301\300\302\ 3\"!\207" 5))

   "List of descriptions of how to add a function.
 Each element has the form (WHERE BYTECODE STACK) where:
   WHERE is a keyword indicating where the function is added.
   "List of descriptions of how to add a function.
 Each element has the form (WHERE BYTECODE STACK) where:
   WHERE is a keyword indicating where the function is added.


@@ -158,12 +161,13 @@ WHERE is a symbol to select an entry in `advice--where-alist'."
     (advice--make-1 (nth 1 desc) (nth 2 desc)
                     function main props)))
 
     (advice--make-1 (nth 1 desc) (nth 2 desc)
                     function main props)))
 

-(defun advice--member-p (function definition)
+(defun advice--member-p (function name definition)

   (let ((found nil))
     (while (and (not found) (advice--p definition))
       (if (or (equal function (advice--car definition))
   (let ((found nil))
     (while (and (not found) (advice--p definition))
       (if (or (equal function (advice--car definition))

-              (equal function (cdr (assq 'name (advice--props definition)))))
-          (setq found t)
+              (when name
+                (equal name (cdr (assq 'name (advice--props definition))))))
+          (setq found definition)

         (setq definition (advice--cdr definition))))
     found))
 
         (setq definition (advice--cdr definition))))
     found))
 


@@ -173,22 +177,27 @@ 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)))
     (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)
           (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)
 
 ;;;###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))))
                            (equal function (cdr (assq 'name props))))

-                       rest))))
+                          (list rest))))))

 
 

-(defvar advice--buffer-local-function-sample nil)
+(defvar advice--buffer-local-function-sample nil
+  "keeps an example of the special \"run the default value\" functions.
+These functions play the same role as t in buffer-local hooks, and to recognize
+them, we keep a sample here against which to compare.  Each instance is
+different, but `function-equal' will hopefully ignore those differences.")

 
 (defun advice--set-buffer-local (var val)
   (if (function-equal val advice--buffer-local-function-sample)
 
 (defun advice--set-buffer-local (var val)
   (if (function-equal val advice--buffer-local-function-sample)


@@ -201,12 +210,12 @@ WHERE is a symbol to select an entry in `advice--where-alist'."
   (declare (gv-setter advice--set-buffer-local))
   (if (local-variable-p var) (symbol-value var)
     (setq advice--buffer-local-function-sample
   (declare (gv-setter advice--set-buffer-local))
   (if (local-variable-p var) (symbol-value var)
     (setq advice--buffer-local-function-sample

+          ;; This function acts like the t special value in buffer-local hooks.

           (lambda (&rest args) (apply (default-value var) args)))))
 
 ;;;###autoload
 (defmacro add-function (where place function &optional props)
   ;; TODO:
           (lambda (&rest args) (apply (default-value var) args)))))
 
 ;;;###autoload
 (defmacro add-function (where place function &optional props)
   ;; TODO:

-  ;; - obsolete with-wrapper-hook (mostly requires buffer-local support).

   ;; - provide some kind of control over ordering.  E.g. debug-on-entry, ELP
   ;;   and tracing want to stay first.
   ;; - maybe let `where' specify some kind of predicate and use it
   ;; - provide some kind of control over ordering.  E.g. debug-on-entry, ELP
   ;;   and tracing want to stay first.
   ;; - maybe let `where' specify some kind of predicate and use it


@@ -225,18 +234,20 @@ call OLDFUN here:
 `:before'      (lambda (&rest r) (apply FUNCTION r) (apply OLDFUN r))
 `:after'       (lambda (&rest r) (prog1 (apply OLDFUN r) (apply FUNCTION r)))
 `:around'      (lambda (&rest r) (apply FUNCTION OLDFUN r))
 `:before'      (lambda (&rest r) (apply FUNCTION r) (apply OLDFUN r))
 `:after'       (lambda (&rest r) (prog1 (apply OLDFUN r) (apply FUNCTION r)))
 `:around'      (lambda (&rest r) (apply FUNCTION OLDFUN r))

+`:override'    (lambda (&rest r) (apply FUNCTION r))

 `:before-while'        (lambda (&rest r) (and (apply FUNCTION r) (apply OLDFUN r)))
 `:before-until'        (lambda (&rest r) (or  (apply FUNCTION r) (apply OLDFUN r)))
 `:after-while' (lambda (&rest r) (and (apply OLDFUN r) (apply FUNCTION r)))
 `:after-until' (lambda (&rest r) (or  (apply OLDFUN r) (apply FUNCTION r)))
 `:before-while'        (lambda (&rest r) (and (apply FUNCTION r) (apply OLDFUN r)))
 `:before-until'        (lambda (&rest r) (or  (apply FUNCTION r) (apply OLDFUN r)))
 `:after-while' (lambda (&rest r) (and (apply OLDFUN r) (apply FUNCTION r)))
 `:after-until' (lambda (&rest r) (or  (apply OLDFUN r) (apply FUNCTION r)))

+`:filter-args' (lambda (&rest r) (apply OLDFUN (funcall FUNCTION r)))
+`:filter-return'(lambda (&rest r) (funcall FUNCTION (apply OLDFUN r)))

 If FUNCTION was already added, do nothing.
 PROPS is an alist of additional properties, among which the following have
 a special meaning:
 - `name': a string or symbol.  It can be used to refer to this piece of advice.
 
 If FUNCTION was already added, do nothing.
 PROPS is an alist of additional properties, among which the following have
 a special meaning:
 - `name': a string or symbol.  It can be used to refer to this piece of advice.
 

-PLACE cannot be a simple variable.  Instead it should either be
-\(default-value 'VAR) or (local 'VAR) depending on whether FUNCTION
-should be applied to VAR buffer-locally or globally.
+If PLACE is a simple variable, only its global value will be affected.
+Use (local 'VAR) if you want to apply FUNCTION to VAR buffer-locally.

 
 If one of FUNCTION or OLDFUN is interactive, then the resulting function
 is also interactive.  There are 3 cases:
 
 If one of FUNCTION or OLDFUN is interactive, then the resulting function
 is also interactive.  There are 3 cases:


@@ -249,15 +260,21 @@ is also interactive.  There are 3 cases:
   (cond ((eq 'local (car-safe place))
          (setq place `(advice--buffer-local ,@(cdr place))))
         ((symbolp place)
   (cond ((eq 'local (car-safe place))
          (setq place `(advice--buffer-local ,@(cdr place))))
         ((symbolp place)

-         (error "Use (default-value '%S) or (local '%S)" place place)))
+         (setq place `(default-value ',place))))

   `(advice--add-function ,where (gv-ref ,place) ,function ,props))
 
 ;;;###autoload
 (defun advice--add-function (where ref function props)
   `(advice--add-function ,where (gv-ref ,place) ,function ,props))
 
 ;;;###autoload
 (defun advice--add-function (where ref function props)

-  (unless (advice--member-p function (gv-deref ref))
+  (let ((a (advice--member-p function (cdr (assq 'name props))
+                             (gv-deref ref))))
+    (when a
+      ;; The advice is already present.  Remove the old one, first.
+      (setf (gv-deref ref)
+            (advice--remove-function (gv-deref ref) (advice--car a))))

     (setf (gv-deref ref)
           (advice--make where function (gv-deref ref) props))))
 
     (setf (gv-deref ref)
           (advice--make where function (gv-deref ref) props))))
 

+;;;###autoload

 (defmacro remove-function (place function)
   "Remove the FUNCTION piece of advice from PLACE.
 If FUNCTION was not added to PLACE, do nothing.
 (defmacro remove-function (place function)
   "Remove the FUNCTION piece of advice from PLACE.
 If FUNCTION was not added to PLACE, do nothing.


@@ -272,6 +289,20 @@ of the piece of advice."
     (macroexp-let2 nil new `(advice--remove-function ,getter ,function)
       `(unless (eq ,new ,getter) ,(funcall setter new)))))
 
     (macroexp-let2 nil new `(advice--remove-function ,getter ,function)
       `(unless (eq ,new ,getter) ,(funcall setter new)))))
 

+(defun advice-function-mapc (f function-def)
+  "Apply F to every advice function in FUNCTION-DEF.
+F is called with two arguments: the function that was added, and the
+properties alist that was specified when it was added."
+  (while (advice--p function-def)
+    (funcall f (advice--car function-def) (advice--props function-def))
+    (setq function-def (advice--cdr function-def))))
+
+(defun advice-function-member-p (advice function-def)
+  "Return non-nil if ADVICE is already in FUNCTION-DEF.
+Instead of ADVICE being the actual function, it can also be the `name'
+of the piece of advice."
+  (advice--member-p advice advice function-def))
+

 ;;;; Specific application of add-function to `symbol-function' for advice.
 
 (defun advice--subst-main (old new)
 ;;;; Specific application of add-function to `symbol-function' for advice.
 
 (defun advice--subst-main (old new)


@@ -282,11 +313,10 @@ of the piece of advice."
   (cond
    ((special-form-p def)
     ;; Not worth the trouble trying to handle this, I think.
   (cond
    ((special-form-p def)
     ;; Not worth the trouble trying to handle this, I think.

-    (error "advice-add failure: %S is a special form" symbol))
-   ((and (symbolp def)
-        (eq 'macro (car-safe (ignore-errors (indirect-function def)))))
-    (let ((newval (cons 'macro (cdr (indirect-function def)))))
-      (put symbol 'advice--saved-rewrite (cons def newval))
+    (error "Advice impossible: %S is a special form" symbol))
+   ((and (symbolp def) (macrop def))
+    (let ((newval `(macro . ,(lambda (&rest r) (macroexpand `(,def . ,r))))))
+      (put symbol 'advice--saved-rewrite (cons def (cdr newval)))

       newval))
    ;; `f' might be a pure (hence read-only) cons!
    ((and (eq 'macro (car-safe def))
       newval))
    ;; `f' might be a pure (hence read-only) cons!
    ((and (eq 'macro (car-safe def))


@@ -297,30 +327,39 @@ of the piece of advice."
 (defsubst advice--strip-macro (x)
   (if (eq 'macro (car-safe x)) (cdr x) x))
 
 (defsubst advice--strip-macro (x)
   (if (eq 'macro (car-safe x)) (cdr x) x))
 

+(defun advice--symbol-function (symbol)
+  ;; The value conceptually stored in `symbol-function' is split into two
+  ;; parts:
+  ;; - the normal function definition.
+  ;; - the list of advice applied to it.
+  ;; `advice--symbol-function' is intended to return the second part (i.e. the
+  ;; list of advice, which includes a hole at the end which typically holds the
+  ;; first part, but this function doesn't care much which value is found
+  ;; there).
+  ;; In the "normal" state both parts are combined into a single value stored
+  ;; in the "function slot" of the symbol.  But the way they are combined is
+  ;; different depending on whether the definition is a function or a macro.
+  ;; Also if the function definition is nil (i.e. unbound) or is an autoload,
+  ;; the second part is stashed away temporarily in the `advice--pending'
+  ;; symbol property.
+  (or (get symbol 'advice--pending)
+      (advice--strip-macro (symbol-function symbol))))
+

 (defun advice--defalias-fset (fsetfun symbol newdef)
 (defun advice--defalias-fset (fsetfun symbol newdef)

+  (unless fsetfun (setq fsetfun #'fset))

   (when (get symbol 'advice--saved-rewrite)
     (put symbol 'advice--saved-rewrite nil))
   (setq newdef (advice--normalize symbol newdef))
   (when (get symbol 'advice--saved-rewrite)
     (put symbol 'advice--saved-rewrite nil))
   (setq newdef (advice--normalize symbol newdef))

-  (let* ((olddef (advice--strip-macro
-                 (if (fboundp symbol) (symbol-function symbol))))
-         (oldadv
-          (cond
-          ((null (get symbol 'advice--pending))
-           (or olddef
-               (progn
-                 (message "Delayed advice activation failed for %s: no data"
-                          symbol)
-                 nil)))
-          ((or (not olddef) (autoloadp olddef))
-           (prog1 (get symbol 'advice--pending)
-             (put symbol 'advice--pending nil)))
-           (t (message "Dropping left-over advice--pending for %s" symbol)
-              (put symbol 'advice--pending nil)
-              olddef))))
-    (let* ((snewdef (advice--strip-macro newdef))
-          (snewadv (advice--subst-main oldadv snewdef)))
-      (funcall (or fsetfun #'fset) symbol
-              (if (eq snewdef newdef) snewadv (cons 'macro snewadv))))))
+  (let ((oldadv (advice--symbol-function symbol)))
+    (if (and newdef (not (autoloadp newdef)))
+        (let* ((snewdef (advice--strip-macro newdef))
+               (snewadv (advice--subst-main oldadv snewdef)))
+          (put symbol 'advice--pending nil)
+          (funcall fsetfun symbol
+                   (if (eq snewdef newdef) snewadv (cons 'macro snewadv))))
+      (unless (eq oldadv (get symbol 'advice--pending))
+        (put symbol 'advice--pending (advice--subst-main oldadv nil)))
+      (funcall fsetfun symbol newdef))))

     
 
 ;;;###autoload
     
 
 ;;;###autoload


@@ -331,12 +370,10 @@ is defined as a macro, alias, command, ..."
   ;; TODO:
   ;; - record the advice location, to display in describe-function.
   ;; - change all defadvice in lisp/**/*.el.
   ;; TODO:
   ;; - record the advice location, to display in describe-function.
   ;; - change all defadvice in lisp/**/*.el.

-  ;; - rewrite advice.el on top of this.

   ;; - obsolete advice.el.
   ;; - obsolete advice.el.

-  (let* ((f (and (fboundp symbol) (symbol-function symbol)))
+  (let* ((f (symbol-function symbol))

         (nf (advice--normalize symbol f)))
         (nf (advice--normalize symbol f)))

-    (unless (eq f nf) ;; Most importantly, if nf == nil!
-      (fset symbol nf))
+    (unless (eq f nf) (fset symbol nf))

     (add-function where (cond
                          ((eq (car-safe nf) 'macro) (cdr nf))
                          ;; Reasons to delay installation of the advice:
     (add-function where (cond
                          ((eq (car-safe nf) 'macro) (cdr nf))
                          ;; Reasons to delay installation of the advice:


@@ -358,48 +395,39 @@ is defined as a macro, alias, command, ..."
 ;;;###autoload
 (defun advice-remove (symbol function)
   "Like `remove-function' but for the function named SYMBOL.
 ;;;###autoload
 (defun advice-remove (symbol function)
   "Like `remove-function' but for the function named SYMBOL.

-Contrary to `remove-function', this will work also when SYMBOL is a macro
-and it will not signal an error if SYMBOL is not `fboundp'.
+Contrary to `remove-function', this also works when SYMBOL is a macro
+or an autoload and it preserves `fboundp'.

 Instead of the actual function to remove, FUNCTION can also be the `name'
 of the piece of advice."
 Instead of the actual function to remove, FUNCTION can also be the `name'
 of the piece of advice."

-  (when (fboundp symbol)
-    (let ((f (symbol-function symbol)))
-      ;; Can't use the `if' place here, because the body is too large,
-      ;; resulting in use of code that only works with lexical-scoping.
-      (remove-function (if (eq (car-safe f) 'macro)
-                           (cdr f)
-                         (symbol-function symbol))
-                       function)
-      (unless (advice--p
-               (if (eq (car-safe f) 'macro) (cdr f) (symbol-function symbol)))
-        ;; Not advised any more.
-        (remove-function (get symbol 'defalias-fset-function)
-                         #'advice--defalias-fset)
-        (if (eq (symbol-function symbol)
-                (cdr (get symbol 'advice--saved-rewrite)))
-            (fset symbol (car (get symbol 'advice--saved-rewrite))))))
-    nil))
-
-;; (defun advice-mapc (fun symbol)
-;;   "Apply FUN to every function added as advice to SYMBOL.
-;; FUN is called with a two arguments: the function that was added, and the
-;; properties alist that was specified when it was added."
-;;   (let ((def (or (get symbol 'advice--pending)
-;;                  (if (fboundp symbol) (symbol-function symbol)))))
-;;     (while (advice--p def)
-;;       (funcall fun (advice--car def) (advice--props def))
-;;       (setq def (advice--cdr def)))))
+  (let ((f (symbol-function symbol)))
+    (remove-function (cond ;This is `advice--symbol-function' but as a "place".
+                      ((get symbol 'advice--pending)
+                       (get symbol 'advice--pending))
+                      ((eq (car-safe f) 'macro) (cdr f))
+                      (t (symbol-function symbol)))
+                     function)
+    (unless (advice--p (advice--symbol-function symbol))
+      ;; Not advised any more.
+      (remove-function (get symbol 'defalias-fset-function)
+                       #'advice--defalias-fset)
+      (let ((asr (get symbol 'advice--saved-rewrite)))
+        (and asr (eq (cdr-safe (symbol-function symbol))
+                     (cdr asr))
+             (fset symbol (car (get symbol 'advice--saved-rewrite)))))))
+  nil)
+
+(defun advice-mapc (fun symbol)
+  "Apply FUN to every advice function in SYMBOL.
+FUN is called with a two arguments: the function that was added, and the
+properties alist that was specified when it was added."
+  (advice-function-mapc fun (advice--symbol-function symbol)))

 
 ;;;###autoload
 
 ;;;###autoload

-(defun advice-member-p (advice function-name)
-  "Return non-nil if ADVICE has been added to FUNCTION-NAME.
+(defun advice-member-p (advice symbol)
+  "Return non-nil if ADVICE has been added to SYMBOL.

 Instead of ADVICE being the actual function, it can also be the `name'
 of the piece of advice."
 Instead of ADVICE being the actual function, it can also be the `name'
 of the piece of advice."

-  (advice--member-p advice
-                    (or (get function-name 'advice--pending)
-                       (advice--strip-macro
-                        (if (fboundp function-name)
-                            (symbol-function function-name))))))
+  (advice-function-member-p advice (advice--symbol-function symbol)))

 
 ;; When code is advised, called-interactively-p needs to be taught to skip
 ;; the advising frames.
 
 ;; When code is advised, called-interactively-p needs to be taught to skip
 ;; the advising frames.


@@ -415,7 +443,7 @@ of the piece of advice."
          (get-next-frame
           (lambda ()
             (setq frame1 frame2)
          (get-next-frame
           (lambda ()
             (setq frame1 frame2)

-            (setq frame2 (internal--called-interactively-p--get-frame i))
+            (setq frame2 (backtrace-frame i #'called-interactively-p))

             ;; (message "Advice Frame %d = %S" i frame2)
             (setq i (1+ i)))))
     (when (and (eq (nth 1 frame2) 'apply)
             ;; (message "Advice Frame %d = %S" i frame2)
             (setq i (1+ i)))))
     (when (and (eq (nth 1 frame2) 'apply)