On Tue, 19 Aug 2008 23:31:17 +0530
Arun Raghavan <ford_prefect@gentoo.org> wrote:
> Ciaran McCreesh wrote:
> > The benefit is that it's a logically separate action, and will avoid
> > all the silliness of people repeatedly changing their minds about
> > which phase should do the eautoreconf calls and so on.
> 
> a) Is this really an issue for maintainers?

It's not a huge issue, any more than src_configure is. Equally, it's not
expensive to implement.

> b) Does it really matter?

In the grand scheme of things, no. In the grand scheme of things, you
only *need* a single src_ function. From a maintainer convenience
perspective, however, src_prepare is marginally more useful than having
a split src_configure.

> c) So the flow will look like:
> 
> ...
> src_unpack
> src_prepare
> src_configure
> src_compile
> ...
> 
> To me this seems like an unnecessary overgeneralisation.

It's a better mapping of the things ebuilds do than the current set of
functions.

The logic is this: lots of ebuilds end up duplicating src_unpack (or,
in future EAPIs, calling 'default') and then adding things to do
preparation work. Experience suggests that the most common reason for
overriding src_unpack is to do preparation work, not to change how
things are unpacked.

(Number-wise... For Exherbo, where the split's already been made,
custom src_prepare functions are three times more common than custom
src_unpack functions. And that figure's significantly lower than what
Gentoo would see, because with exheres-0 'default' functions you don't
need to write a src_prepare if you're merely applying patches.)

> The *only* potential "benefit" I see here is that at some point of
> time in the nebulous future, it might be possible to tell the PM to
> always skip src_prepare in order to give a system where everything is
> "vanilla".

Such a system wouldn't be usable... Not all of Gentoo's patches are
non-essential.

-- 
Ciaran McCreesh