[Distutils] it's happened - wheels without sdists (flit)

[Paul Moore]

On 1 April 2015 at 00:03, Nick Coghlan <ncoghlan at gmail.com> wrote:
>> It's not quite that simple, I know. But until we work out how to do
>> something useful with a sdist that we can't do with a dev checkout,
>> it's hard to justify treating sdists specially.
>
> I see it as more a matter of eventually migrating to a "devdir -> sdist ->
> wheel -> installed" build & deployment pipeline, where the tools used at
> each stage are only required to support the transition to the next stage
> rather than having to support the whole pipeline as setuptools does.
> (setup.py support would necessarily remain as a backwards compatibility
> requirement)

I wasn't particularly clear - my apologies. By "we" I meant "pip" in
this context. Users expect to be able to do "pip install
/dev/directory" and have it "just work". Internally, pip can dor the
dev->sdist->wheel->install dance, certainly, and that's the ultimate
goal, I agree. What I was trying to say that there's no obvious
benefit to pup from splitting out the dev->sdist and sdist->wheel
step. We can just as easily run setup.py bdist_wheel in a dev
directory directly.

I know we can *also* just run "setup.py install" from a dev directory
(we do now), but there are benefits in not doing so - splitting out
the step of building a wheel lets us cache the wheels and speed up the
process, because installing a wheel is quicker than building from
source. So what I'm saying is that we need similar motivating benefits
to justify splitting out the "build a sdist" step, and it's not yet
clear to me what those would be.

Paul