GNU bug report logs - #38694
26.1; update-*-autoloads fails with local generated-autoload-file

Previous Next

To add a comment to this bug, you must first unarchive it, by sending
a message to control AT debbugs.gnu.org, with unarchive 38694 in the body.
You can then email your comments to 38694 AT debbugs.gnu.org in the normal way.

Toggle the display of automated, internal messages from the tracker.

Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Braun Gábor <braungb88 <at> gmail.com>
To: bug-gnu-emacs <at> gnu.org
Subject: 26.1; update-*-autoloads fails with local generated-autoload-file
Date: Fri, 20 Dec 2019 20:16:29 +0100

Let the current directory have only the following two files:

------------------ test-foo.el -------------------------
;;;###autoload
(defun test-foo-fun ()
  "FOO: a function just for testing."
  t)

;; Local Variables:
;; generated-autoload-file: "foo-autoloads.el"
;; End:
--------------------------------------------------------


------------------ test-bar.el -------------------------
;;;###autoload
(defun test-bar-fun ()
  "BAR: a noop test function."
  nil)
--------------------------------------------------------

1) Do the following:

emacs -Q test-foo.el

M-x update-file-autoloads RET
test-bar.el RET
test-autoloads.el RET


It produces an error message, which I copied from buffer *Messages*:

autoload-generate-file-autoloads: DIRECTORY/test-bar.el:0:0: error: 
wrong-type-argument: (stringp nil)

where in place of DIRECTORY there is the directory the files
above reside.

2) Similar as above but try generating autoloads for the whole
directory:

emacs -Q test-foo.el

M-x update-directory-autoloads RET RET
test-autoloads.el RET


This time the error message is (again from buffer *Messages*):

autoload-generate-file-autoloads: test-bar.el:0:0: error: wrong-type-
argument: (stringp nil)


IMHO, the root of the problem is that update-file-autoloads and
update-directory-autoloads bind generated-autoload-file buffer locally
(as it is a file local variable in test-foo.el) but intend to bind the
default value.  Note that the docstrings of both functions
mention the case of generated-autoload-file being buffer-local, so
they ought to support this case.

As the documented behaviour of these functions do not
depend on the current buffer, I propose to simply switch to a
temporary buffer so that the local settings don't interfere.
This is a preemptive measure of other similar latent problems.

Admittedly, creating a temporary buffer just to bind variables'
default value seems to be wasteful, and I am very interested in
learning a better, more idiomatic approach.

All in all, the patch is the following, adding wrappers
`(with-temp-buffer ...)'.  (The code has not been reindented, 
reformatted
solely to keep the patch readable.)

--- lisp/emacs-lisp/autoload.el
+++ lisp/emacs-lisp/autoload.el
@@ -916,6 +916,9 @@ update-file-autoloads
   (interactive (list (read-file-name "Update autoloads for file: ")
                     current-prefix-arg
                     (read-file-name "Write autoload definitions to 
file: ")))
+  ;; The temporary buffer is only to bind the default value of e.g.,
+  ;; `generated-autoload-file'.  The current buffer is irrelevant.
+  (with-temp-buffer
   (let* ((generated-autoload-file (or outfile generated-autoload-file))
         (autoload-modified-buffers nil)
         ;; We need this only if the output file handles more than one 
input.
@@ -927,6 +930,7 @@ update-file-autoloads
       (if (called-interactively-p 'interactive)
           (message "Autoload section for %s is up to date." file)))
     (if no-autoloads file)))
+  )

 (defun autoload-find-destination (file load-name)
   "Find the destination point of the current buffer's autoloads.
@@ -1028,6 +1032,9 @@ update-directory-autoloads
 file binds `generated-autoload-file' as a file-local variable,
 write its autoloads into the specified file instead."
   (interactive "DUpdate autoloads from directory: ")
+  ;; The temporary buffer is only to bind default value of e.g.,
+  ;; `generated-autoload-file'.  The current buffer is irrelevant.
+  (with-temp-buffer
   (let* ((files-re (let ((tmp nil))
                     (dolist (suf (get-load-suffixes))
                        ;; We don't use module-file-suffix below because
@@ -1142,6 +1149,7 @@ update-directory-autoloads
       ;; In case autoload entries were added to other files because of
       ;; file-local autoload-generated-file settings.
       (autoload-save-buffers))))
+  )

 (define-obsolete-function-alias 'update-autoloads-from-directories
     'update-directory-autoloads "22.1")



Best wishes,

     Gábor


In GNU Emacs 26.1 (build 2, x86_64-pc-linux-gnu, GTK+ Version 3.24.5)
 of 2019-09-23, modified by Debian built on x86-grnet-01
Windowing system distributor 'The X.Org Foundation', version 
11.0.12004000
System Description:	Debian GNU/Linux 10 (buster)

Recent messages:
Generating autoloads for ~/.emacs.d/autoload-test/test-foo.el...
(New file)
Generating autoloads for ~/.emacs.d/autoload-test/test-foo.el...done
Quit
Generating autoloads for ~/.emacs.d/autoload-test/test-bar.el...
(New file)
Generating autoloads for ~/.emacs.d/autoload-test/test-bar.el...done
scroll-down-command: Beginning of buffer
C-c M-w is undefined
scroll-up-command: End of buffer

Configured using:
 'configure --build x86_64-linux-gnu --prefix=/usr
 --sharedstatedir=/var/lib --libexecdir=/usr/lib
 --localstatedir=/var/lib --infodir=/usr/share/info
 --mandir=/usr/share/man --enable-libsystemd --with-pop=yes
 --enable-locallisppath=/etc/emacs:/usr/local/share/emacs/26.1/site-
lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/26.1/site-lisp:/
usr/share/emacs/site-lisp
 --with-sound=alsa --without-gconf --with-mailutils --build
 x86_64-linux-gnu --prefix=/usr --sharedstatedir=/var/lib
 --libexecdir=/usr/lib --localstatedir=/var/lib
 --infodir=/usr/share/info --mandir=/usr/share/man --enable-libsystemd
 --with-pop=yes
 --enable-locallisppath=/etc/emacs:/usr/local/share/emacs/26.1/site-
lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/26.1/site-lisp:/
usr/share/emacs/site-lisp
 --with-sound=alsa --without-gconf --with-mailutils --with-x=yes
 --with-x-toolkit=gtk3 --with-toolkit-scroll-bars 'CFLAGS=-g -O2
 -fdebug-prefix-map=/build/emacs-StqULU/emacs-26.1+1=. -fstack-
protector-strong
 -Wformat -Werror=format-security -Wall' 'CPPFLAGS=-Wdate-time
 -D_FORTIFY_SOURCE=2' LDFLAGS=-Wl,-z,relro'

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND GPM DBUS GSETTINGS NOTIFY
ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11 THREADS LIBSYSTEMD LCMS2

Important settings:
  value of $LANG: hu_HU.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Emacs-Lisp

Minor modes in effect:
  diff-auto-refine-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message rmc puny seq byte-opt bytecomp
byte-compile cconv dired dired-loaddefs format-spec rfc822 mml mml-sec
password-cache epa derived epg epg-config gnus-util rmail rmail-loaddefs
mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils
mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr
mail-utils cl-macs gv pcase ediff-ptch ediff-merg ediff-wind ediff-diff
ediff-mult ediff-help ediff-init cl-loaddefs cl-lib ediff-util ediff
jka-compr thingatpt find-func autoload radix-tree lisp-mnt vc-git
diff-mode easymenu easy-mmode elec-pair time-date mule-util tooltip
eldoc electric uniquify ediff-hook vc-hooks lisp-float-type mwheel
term/x-win x-win term/common-win x-dnd tool-bar dnd fontset image
regexp-opt fringe tabulated-list replace newcomment text-mode elisp-mode
lisp-mode prog-mode register page menu-bar rfn-eshadow isearch timer
select scroll-bar mouse jit-lock font-lock syntax facemenu font-core
term/tty-colors frame cl-generic cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932
hebrew greek romanian slovak czech european ethiopic indian cyrillic
chinese composite charscript charprop case-table epa-hook jka-cmpr-hook
help simple abbrev obarray minibuffer cl-preloaded nadvice loaddefs
button faces cus-face macroexp files text-properties overlay sha1 md5
base64 format env code-pages mule custom widget hashtable-print-readable
backquote dbusbind inotify lcms2 dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty
make-network-process emacs)

Memory information:
((conses 16 116513 9893)
 (symbols 48 22483 1)
 (miscs 40 106 201)
 (strings 32 34406 1337)
 (string-bytes 1 943432)
 (vectors 16 17409)
 (vector-slots 8 538130 13522)
 (floats 8 69 226)
 (intervals 56 380 0)
 (buffers 992 20))

Message #8 received at 38694 <at> debbugs.gnu.org (full text, mbox):

From: Lars Ingebrigtsen <larsi <at> gnus.org>
To: Braun Gábor <braungb88 <at> gmail.com>
Cc: 38694 <at> debbugs.gnu.org
Subject: Re: bug#38694: 26.1; update-*-autoloads fails with local
 generated-autoload-file
Date: Fri, 21 Aug 2020 14:01:53 +0200

Braun Gábor <braungb88 <at> gmail.com> writes:

> Let the current directory have only the following two files:

[...]

> ;; Local Variables:
> ;; generated-autoload-file: "foo-autoloads.el"
> ;; End:

> M-x update-file-autoloads RET
> test-bar.el RET
> test-autoloads.el RET
>
> It produces an error message, which I copied from buffer *Messages*:
>
> autoload-generate-file-autoloads: DIRECTORY/test-bar.el:0:0: error: 
> wrong-type-argument: (stringp nil)

I can confirm this bug.

[...]

> IMHO, the root of the problem is that update-file-autoloads and
> update-directory-autoloads bind generated-autoload-file buffer locally
> (as it is a file local variable in test-foo.el) but intend to bind the
> default value.  Note that the docstrings of both functions
> mention the case of generated-autoload-file being buffer-local, so
> they ought to support this case.
>
> As the documented behaviour of these functions do not
> depend on the current buffer, I propose to simply switch to a
> temporary buffer so that the local settings don't interfere.
> This is a preemptive measure of other similar latent problems.
>
> Admittedly, creating a temporary buffer just to bind variables'
> default value seems to be wasteful, and I am very interested in
> learning a better, more idiomatic approach.

I don't think there is, and that's perhaps unfortunate.  What we have
here is a pretty unusual situation, though.

> +  ;; The temporary buffer is only to bind the default value of e.g.,
> +  ;; `generated-autoload-file'.  The current buffer is irrelevant.
> +  (with-temp-buffer
>    (let* ((generated-autoload-file (or outfile generated-autoload-file))

But I don't think this is the right way to fix this?  We want to heed
the buffer-local value of generated-autoload-file, and we want to bind
the global value of generated-autoload-file, I think?  Otherwise, what
would be the point of

> ;; Local Variables:
> ;; generated-autoload-file: "foo-autoloads.el"
> ;; End:

I'm not very familiar with this code, though, so I may be misreading it.

So the patch would be something like

+  (let ((autoload-file (or outfile generated-autoload-file)))
+    (with-temp-buffer
+      (let* ((generated-autoload-file autoload-file)

Or more complete (with indentation changes) below.

Does that makes sense?

diff --git a/lisp/emacs-lisp/autoload.el b/lisp/emacs-lisp/autoload.el
index 2eef451200..ad39f5642b 100644
--- a/lisp/emacs-lisp/autoload.el
+++ b/lisp/emacs-lisp/autoload.el
@@ -924,17 +924,20 @@ update-file-autoloads
   (interactive (list (read-file-name "Update autoloads for file: ")
 		     current-prefix-arg
 		     (read-file-name "Write autoload definitions to file: ")))
-  (let* ((generated-autoload-file (or outfile generated-autoload-file))
-	 (autoload-modified-buffers nil)
-	 ;; We need this only if the output file handles more than one input.
-	 ;; See https://debbugs.gnu.org/22213#38 and subsequent.
-	 (autoload-timestamps t)
-         (no-autoloads (autoload-generate-file-autoloads file)))
-    (if autoload-modified-buffers
-        (if save-after (autoload-save-buffers))
-      (if (called-interactively-p 'interactive)
-          (message "Autoload section for %s is up to date." file)))
-    (if no-autoloads file)))
+  (let ((autoload-file (or outfile generated-autoload-file)))
+    (with-temp-buffer
+      (let* ((generated-autoload-file autoload-file)
+	     (autoload-modified-buffers nil)
+	     ;; We need this only if the output file handles more than
+	     ;; one input.  See https://debbugs.gnu.org/22213#38 and
+	     ;; subsequent.
+	     (autoload-timestamps t)
+             (no-autoloads (autoload-generate-file-autoloads file)))
+        (if autoload-modified-buffers
+            (if save-after (autoload-save-buffers))
+          (if (called-interactively-p 'interactive)
+              (message "Autoload section for %s is up to date." file)))
+        (if no-autoloads file)))))
 
 (defun autoload-find-destination (file load-name)
   "Find the destination point of the current buffer's autoloads.


-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

Message #13 received at 38694 <at> debbugs.gnu.org (full text, mbox):

From: Lars Ingebrigtsen <larsi <at> gnus.org>
To: Braun Gábor <braungb88 <at> gmail.com>
Cc: 38694 <at> debbugs.gnu.org
Subject: Re: bug#38694: 26.1; update-*-autoloads fails with local
 generated-autoload-file
Date: Fri, 02 Oct 2020 04:37:58 +0200

This has now been fixed in Emacs 28 with the introduction of the new
`make-directory-autoloads' command.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.