Re: beta-tester call draft

[Bernhard Voelker <mail@bernhard-voelker.de>]

On 4/20/24 02:22, Bruno Haible wrote:
> Hi,
>
> It's now time to call for beta-testers of the Python gnulib-tool.
> I plan to post the same text to info-gnu and to planet.gnu.org.
>
> Here is a draft. Please comment!

findutils results ...

>   ---------------------------------------------------------------------
> GNU gnulib: calling for beta-testers
>
> If you are developer on a package that uses GNU gnulib as part of its
> build system:
>
> gnulib-tool has been known for being slow for many years. We have
> listened to your complaints. A rewrite of gnulib-tool in another
> programming language (Python) is ready for beta-testing. It is
> between 8 times and 100 times faster than the original gnulib-tool.
>
> Both implementations should behave identically, that is, produce
> the same generated files and the same output. You can help us ensure
> this, through the following steps:
>
>    1. Make sure you have Python (version 3.7 or newer) installed on
>       your machine.

$ python3 --version
Python 3.11.8

>    2. Update your gnulib checkout. (For some packages, it comes as a
>       git submodule named 'gnulib'.) Like this:
>         $ git pull
>       Set the environment variable GNULIB_SRCDIR, pointing to this checkout.

done: gnulib 237cbf1c

>    3. Set an environment variable that enables checking that the two
>       implementations behave the same:
>         $ export GNULIB_TOOL_IMPL=sh+py

done

>    4. Clean the built files of your package:
>         $ make -k distclean

Used
   $ git clean -xdfq && ./bootstrap && ./configure && && make -k distclean
to get a clean working environment.

>    5. Regenerate the fetched and generated files of your package.
>       Depending on the packge, this may be a command such as
>         $ ./bootstrap --no-git --gnulib-srcdir=$GNULIB_SRCDIR
>       or
>         $ export GNULIB_SRCDIR; ./autopull.sh; ./autogen.sh
>       or, if no such script is available:
>         $ $GNULIB_SRCDIR/gnulib-tool --update
>       If there is a failure, due to differences between the 'sh' and 'py'
>       results, please report it to <bug-gnulib@gnu.org>.

How would such a failure look like? Or how should one check?

   $ ./bootstrap

no error. :-)

Regarding the timings:

$ export GNULIB_TOOL_IMPL=sh
$ time ./bootstrap
...
real	1m29.778s
ser	1m21.919s
sys	0m19.456s

$ export GNULIB_TOOL_IMPL=py
$ time ./bootstrap
...
real	0m26.536s
user	0m22.881s
sys	0m0.884s

$ time AUTORECONF=true ./bootstrap --skip-po
...
real	0m3.369s
user	0m2.979s
sys	0m0.520s

Cool!

>    6. If this invocation was successful, you can trust the rewritten
>       gnulib-tool and use it from now on, by setting the environment
>       variable
>         $ export GNULIB_TOOL_IMPL=py
>
>    7. Continue with
>         $ ./configure
>         $ make
>       as usual.
>
> And enjoy the speed! The rewritten gnulib-tool was implemented by
> Dmitry Selyutin, Collin Funk, and me.
>   ---------------------------------------------------------------------

There will come the question whether there are plans to drop the 'sh' mode,
or if or how long both modes will be maintained in parallel.

Have a nice day,
Berny