Re: [gentoo-dev] Ebuild Generators

[Gerion Entrup]

Am Montag, 3. Februar 2020, 13:19:52 CET schrieb Benda Xu:
> Hi Gerion,
>
> Gerion Entrup <gerion.entrup@×××××.de> writes:
>
> >> Yes, that makes a lot of sense.  The R overlay follows this model.  Most
> >> of the ebuilds are automated.  When an ebuild generation fails, we add
> >> the ebuild manually, understand it and then update the generator to
> >> cover it in the future.
> >
> > Is this possible in all cases? I think of adding custom patches,
> > appropriate mapping of dependencies, check for things like desktop
> > icon cache...
>
> That's too complex to handle automatically.  Luckily, in R overlay, such
> packages are less than 5%.  An ebuild generator is based on the
> observation that many language-specific packages are trivial to fetch,
> compile and install.
>
> >> > I'm only "maintaining" an overlay so maybe I'm  missing experience
> >> > but I often have wished a tool that automatically parses the language specific
> >> > packaging files and is able to generate a primitive ebuild out of that.
> >> > Maybe it even can do this in an interactive way:
> >> > "Hey, upstream needs the dependency 'foo'. In the Gentoo packages I have found
> >> > 'dev-bar/foo' and 'dev-util/foo'. What is the correct one?"
> >>
> >> Yes, that's the way R overlay is working.  And I have a similar plan and
> >> proof-of-concept solution for the Java Maven overlay.
> >
> > Nice to hear. I think, it is meaningful to solve all generation with one
> > tool. Maybe it can even "recognize" the used build system and package
> > database. Is this your plan, too?
>
> No, I don't think it possible as far as I can see...  That would be a
> strong AI.
I mean only on a primitive base:
```
if link contains "pypi":
    # it's a Python package from pypi
    handle_pypi()
elif work_tree contains "setup.py":
    # it's a Python package
    handle_generic_python()
elif work_tree contains "meson.build":
    handle_meson_package()
...
```

Best,
Gerion