[Zope-dev] Re: buildout 'versions' and 'develop' conflict

[Martijn Faassen]

David Pratt wrote:
> Hi. I agree with Jim. Buildout is doing the right thing. This is not a 
> conflict since you have explicitly identified the software with a 
> version already. I think the right thing to do under the circumstances 
> would be to append a custom versions.cfg to nail the versions you want. 
> KGS versions is a point in time list and it does not apply to the full 
> scope of what buildout is being used for. I believe this should be kept 
> in mind since it serves more than z3.
> 
> Changes to buildout to have it automatically do the 'right' thing opens 
> the implicit versus explicit argument. A developer would then need to be 
> aware of the implicit cases that would cause a different software 
> selection. Much like zcml configuration in zope, I want to tell buildout 
> what to do and have it do it without surprise (or for that matter 
> fighting any implicit nature folks may be inclined to give it). While I 
> understand the concern about the development egg for your build, I would 
> see any move in this direction as corrupting the nature of buildout to 
> 'do what you have told it to do'

I want to tell buildout what to do have it do it without surprise as 
well. I was surprised when it didn't do what I expected: give priority 
to the develop package. Why else would I choose to put it on the develop 
line?

I take it you have run into this and weren't surprised at all, then?

I think the explicit versus implicit discussion has no place here. 
Placing a package on the 'develop' line is a very explicit action, and 
you place it on that line because you want to *develop on it*. Having 
another package being picked up is surprising.

I realize that it has a reason: it does what you tell it do. But lists 
of locked versions are things that are frequently maintained offline - 
even sitting off on some URL, and maintained by someone else. Yes, 
indirectly you are telling buildout about versions, but you may not be 
very aware of it. These are long lists, after all. It'd be nice if these 
lists could be treated as mostly opaque (encapsulation) and that you can 
simply look at what's in setup.py instead.

That is not possible now. You need to *know* that it lists the package 
you are trying to hack on, and you need to know that you need to add it 
to [versions]. The workaround I find myself using frequently now is this:

[versions]
the_package =

I don't see the point when I already say this in 'develop'.

Regards,

Martijn