[Zope3-dev] Re: [Zope-dev] Re: More arguments for "z" (was Re: Zope and zope)

[Casey Duncan]

On Thu, 15 Apr 2004 10:31:39 -0400
Barry Warsaw <barry at zope.com> wrote:

> On Thu, 2004-04-15 at 10:23, Jim Fulton wrote:
> 
> > Each separately distributed package will have a DEPENDENCIES.cfg
> > that is created by hand and that *constrains* dependencies on other
> > packages. It makes explicit the intended dependencies. Dependencies
> > not listed here are bugs.  Adding depenencies to this file should be
> > considered a big deal.
> 
> That's very comforting!  I like that it forces developers to be
> deliberate when adding cross-subpackage dependencies.

Additionally (and Jim and I have discussed this amongst ourselves) I
feel strongly that the dependancies should be enforced by tests. That
is, if you introduce and errant dependancy (by adding an import to a new
package not in the stdlib or DEPENDANCIES.cfg) that it break a
dependancy test.

The dependancy tests might need to be separate from unittests because
they would probably require an import hook or somesuch. Perhaps a tool
like pychecker could be leveraged or extended to provide this service.
At a minimum this test would need to be run before packaging a
distribution, but ideally would happen more often.

Some of the reasons that undesired dependancies are added is because A.
it is very easy to do and B. very few people know what dependencies
would be undesireable. Having an automated way to verify dependancies
would put the onus on each developer to make those decisions with much
more careful consideration.

-Casey