GNU bug report logs - #21742
25.0.50; Document that ert-deftest expands all macros

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 21742 in the body.
You can then email your comments to 21742 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: immerrr again <immerrr <at> gmail.com>
To: bug-gnu-emacs <at> gnu.org
Subject: 25.0.50; Document that ert-deftest expands all macros
Date: Fri, 23 Oct 2015 11:55:45 +0300

I wrote a library ample-regexps [1] that does some macro magic to extend
rx and ran into an issue with ert when tests started failing without any
explanation.  I started digging and here's what I found.

The library provides a macro called `define-arx` which roughly expands
to ([2])

   (eval-and-compile
     (defvar SOME-VAR ...)
     (defun SOME-FUN (...) ...)
     (defmacro SOME-MACRO (...)
       (SOME-FUN ...))
     ...)

The whole expansion is wrapped into eval-and-compile so that it can be
used in a library during byte-compilation.

I wrote a macro to use in tests that expands to roughly

  (progn
    (define-arx ...)
    (unwind-protect
        ,@body
      (fmakunbound SOME-MACRO)
      (fmakunbound SOME-FUN)
      (makunbound SOME-VAR)))

The macro worked when executed manually, but not during tests.

I started grepping and xref-ing through the code till I found that
ert-deftest includes cl-macrolet which in turn runs macroexpand-all on
the test definition.  Quite expectedly, it expands the define-arx macro
that results in eval-and-compile which is also expanded and all that's
left in the resulting test definition is a symbol.  More importantly,
all side effects, i.e. function/macro definitions happen during test
definition while they should really happen during test execution.

I ended up using (eval (quote (define-arx ...))) to prevent early
expansion, but it would really be nice if this was documented (would
have saved me an hour-something of what-is-going-on and couple hours of
how-do-i-stop-that).  Or if that expansion didn't happen in the first
place, but I guess that's not easy since it does that to expand all the
(should ...) forms and test helpers to improve test run time.

1. https://github.com/immerrr/ample-regexps.el
2. https://github.com/immerrr/ample-regexps.el/blob/8368cc16e724cea1f60755fe40e25fe374b24418/ample-regexps.el#L339-L371



In GNU Emacs 25.0.50.10 (x86_64-unknown-linux-gnu, GTK+ Version 3.4.2)
 of 2015-10-12
Repository revision: 149066dbfc7f11c40f6dbed70a3279153bf3ab7a
Windowing system distributor 'The X.Org Foundation', version 11.0.11103000
System Description:    Ubuntu 12.04.5 LTS

Configured using:
 'configure --prefix=/home/immerrr/.local'

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

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

Major mode: el

Minor modes in effect:
  global-git-commit-mode: t
  global-undo-tree-mode: t
  undo-tree-mode: t
  diff-auto-refine-mode: t
  nameless-mode: t
  whitespace-mode: t
  flycheck-mode: t
  guide-key-mode: t
  global-company-mode: t
  company-mode: t
  pyvenv-mode: t
  paredit-mode: t
  auto-compile-on-save-mode: t
  auto-compile-mode: t
  recentf-mode: t
  shell-dirtrack-mode: t
  async-bytecomp-package-mode: t
  projectile-global-mode: t
  projectile-mode: t
  yas-global-mode: t
  yas-minor-mode: t
  save-place-mode: t
  show-paren-mode: t
  override-global-mode: t
  global-linum-mode: t
  linum-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  size-indication-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
Making completion list... [2 times]

mouse-2, RET: find function's definition
uncompressing bytecomp.el.gz...done
Mark set
Mark saved where search started

Mark set

Making completion list...

Load-path shadows:
/home/immerrr/.emacs.d/elpa/helm-20150921.1209/helm-multi-match hides
/home/immerrr/.emacs.d/elpa/helm-core-20150921.1209/helm-multi-match

Features:
(shadow sort mail-extr emacsbug sendmail yaml-mode gravatar url-cache
git-rebase log-view vc-annotate macrostep ielm goto-chg novice
network-stream nsm starttls warnings company-jedi jedi-core epc ctable
concurrent python bs ag vc-svn find-dired mc-mark-more
multiple-cursors-core rect make-mode magit-blame magit-stash
magit-bisect magit-remote magit-commit magit-sequence magit magit-apply
magit-wip magit-log magit-diff smerge-mode magit-core magit-process
magit-popup magit-mode magit-git crm magit-section magit-utils
git-commit log-edit message rfc822 mml mml-sec mailabbrev gmm-utils
mailheader pcvs-util add-log with-editor server ert ewoc debug align
tabify two-column iso-transl face-remap cc-mode cc-fonts cc-guess
cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs ido seq
eieio-opt speedbar sb-image ezimage dframe trace undo-tree diff misearch
multi-isearch pulse jka-compr executable edebug test-helper
ample-regexps vc vc-dispatcher vc-git diff-mode company-elisp nameless
disp-table whitespace flycheck find-func subr-x guide-key s
ucs-normalize popwin image-file winner wgrep traad request-deferred
request url-http tls url-auth url-gw mail-utils popup python-environment
deferred company-files company-oddmuse company-keywords company-etags
etags xref project company-gtags company-dabbrev-code company-dabbrev
company-capf company-cmake company-xcode company-clang company-semantic
company-eclim company-template company-css company-nxml company-bbdb
company pyvenv paredit auto-compile packed tramp-cache tramp-sh recentf
tree-widget wid-edit helm-projectile helm-files rx image-dired tramp
tramp-compat tramp-loaddefs trampver shell pcomplete format-spec dired-x
dired-aux ffap helm-tags helm-bookmark helm-adaptive helm-info bookmark
pp helm-external helm-net browse-url xml url url-proxy url-privacy
url-expand url-methods url-history url-cookie url-domsuf url-util
url-parse auth-source gnus-util password-cache url-vars mailcap
helm-buffers helm-grep helm-regexp helm-plugin helm-elscreen helm-utils
helm-locate helm-help helm-types helm-config helm-easymenu
async-bytecomp async helm-aliases helm helm-source eieio-compat eieio
eieio-core cl-macs helm-multi-match helm-lib dired projectile grep
compile comint ansi-color ibuf-ext ibuffer thingatpt yasnippet cl gv
saveplace hydra ring lv paren solarized-dark-theme solarized-theme
solarized dash byte-opt edmacro kmacro mmr-bootstrap quelpa-use-package
cl-seq quelpa package-build mm-decode mm-bodies mm-encode mail-parse
rfc2231 rfc2047 rfc2045 ietf-drums mm-util help-fns mail-prsvr json
lisp-mnt use-package bytecomp byte-compile cl-extra help-mode cconv
bind-key easy-mmode cl-loaddefs pcase cl-lib diminish linum-ex
bar-cursor advice mmr-minimal mmr-ediff windmove finder-inf info package
easymenu epg-config time-date mule-util tooltip eldoc electric uniquify
ediff-hook vc-hooks lisp-float-type mwheel x-win term/common-win x-dnd
tool-bar dnd fontset image regexp-opt fringe tabulated-list newcomment
elisp-mode lisp-mode prog-mode register page menu-bar rfn-eshadow timer
select scroll-bar mouse jit-lock font-lock syntax facemenu font-core
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 charscript
case-table epa-hook jka-cmpr-hook help simple abbrev 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
dynamic-setting system-font-setting font-render-setting move-toolbar gtk
x-toolkit x multi-tty make-network-process emacs)

Memory information:
((conses 16 1017131 97896)
 (symbols 48 52825 1)
 (miscs 40 11688 6032)
 (strings 32 126665 12804)
 (string-bytes 1 3827188)
 (vectors 16 85648)
 (vector-slots 8 1983427 52910)
 (floats 8 1126 2620)
 (intervals 56 75316 4827)
 (buffers 976 104)
 (heap 1024 95787 17598))

Message #8 received at 21742 <at> debbugs.gnu.org (full text, mbox):

From: Lars Ingebrigtsen <larsi <at> gnus.org>
To: immerrr again <immerrr <at> gmail.com>
Cc: 21742 <at> debbugs.gnu.org
Subject: Re: bug#21742: 25.0.50; Document that ert-deftest expands all macros
Date: Sat, 12 Oct 2019 21:35:47 +0200

immerrr again <immerrr <at> gmail.com> writes:

> I started grepping and xref-ing through the code till I found that
> ert-deftest includes cl-macrolet which in turn runs macroexpand-all on
> the test definition.  Quite expectedly, it expands the define-arx macro
> that results in eval-and-compile which is also expanded and all that's
> left in the resulting test definition is a symbol.  More importantly,
> all side effects, i.e. function/macro definitions happen during test
> definition while they should really happen during test execution.

I've now added this to the doc string.

-- 
(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.