[gentoo-dev] Re: Re: [RFC] What features should be included in EAPI 2?

[Steve Long <slong@rathaus.eclipse.co.uk>]

Ciaran McCreesh wrote:

> 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.
Er, that would be the new src_configure?

>> 
>> 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.
>
How so?

From a user point of view, and from a maintenance point of view,
src_configure is very useful.
 
>> 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.
>
Yeah I've always seen src_unpack as being more cogent to preparation of src
files, than to actually untarring stuff. So what? Why make a new phase
which every new dev has to know about, and we have to provide pre_ and
post_ hooks for, when the existing phase covers the usage fine?
 
> (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.)
>
Well it's easy enough to auto-apply patches, given a declaration in the
ebuild (since files for all versions are in the same dir.) It certainly
doesn't need a new phase.
 
>> 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.
> 
So the real, fully-defined, explicit benefit is..