Re: [gentoo-dev] [PATCH 1/3] dev-util/meson: install meson-array script

[William Hubbs]

On Sat, Dec 12, 2020 at 09:22:06PM -0500, Mike Gilbert wrote:
> On Sat, Dec 12, 2020 at 9:09 PM William Hubbs <williamh@g.o> wrote:
> >
> > On Sat, Dec 12, 2020 at 04:25:48PM -0500, Mike Gilbert wrote:
> > > On Sat, Dec 12, 2020 at 3:48 PM William Hubbs <williamh@g.o> wrote:
> > > > If both /usr/bin/python and /usr/bin/python3 are going away, the best
> > > > choice would be to add functionality to python-exec or eselect python to tell us
> > > > the path to the default python interpretor. Once we know that we call it
> > > > directly.
> > >
> > > I don't think they are "going away". There is a USE flag on
> > > dev-lang/python-exec that makes them optional, and I think it will be
> > > forcibly enabled for the foreseeable future.
> > >
> > > > Please do not apply this patch to meson; I think we can figure something
> > > > out that is better.
> > >
> > > I think installing a small script to help translate arguments from one
> > > format to another is a reasonable solution.
> >
> >  I think we should look at the eclass to see if we can provide functions
> >  that can be used by consumers to handle this.
>
> I don't really understand what you mean by this. I am converting one
> internal bash function into an external script so that its python
> dependencies can be better defined and managed.

What I mean is, ebuilds should not be calling _meson_env_array at all
since it is defined and documented as an eclass internal function.

I would like to know more about what the gallium-nine-standalone ebuild
is doing and why it needs to call a meson.eclass internal function.

On the other hand, if _meson_env_array is meant to be called by ebuilds,
we need to rename it and improve the documentation for it in the eclass.

> > Also, I don't think your script will run if native-symlinks is disabled since in
> > that setting /usr/bin/python would not exist.
>
> python_doscript updates the shebang before installing the script.
 
 Ok, I didn't know python_doscript does this, but couldn't we just
 change line 129 in the eclass to "python3 -c ..."?

> > I question the value of the native-symlinks  use flag on python-exec
> > unless there is a way to query the path of the default python
> > interpretor.
>
> Regardless, I don't see how that makes my solution a bad thing. It
> ensures that the code will be executed by a known/support/tested
> version of python.
>

I'm not sure how useful the script is as a command, so I don't think it
should be installed that way, but I do want to hear more about this,
both from you and chewi. :-)

William