Re: library dependencies and unit/integration testing

[Ted Zlatanov <tzz@lifelogs.com>]

On Mon, 01 Mar 2010 10:59:47 -0700 Tom Tromey <tromey@redhat.com> wrote: 

>>>>>> "Ted" == Ted Zlatanov <tzz@lifelogs.com> writes:
Ted> What capabilities does Emacs offer for tracking library dependencies
Ted> beyond 'require and `load-history'?  I think versions (as stated by the
Ted> Version header) are not tracked and that's a basic requirement.  Then,
Ted> how would a library state it depends on "foo v.1 or later and bar v.2
Ted> exactly"?

Tom> Emacs doesn't provide much.

Tom> package.el defines an extension to the header comments for tracking
Tom> dependencies.  It looks like (example from ruby-compilation):

Tom> ;;; Package-Requires: ((ruby-mode "1.0") (inf-ruby "2.0"))

Tom> This just means that this package requires ruby-mode >= 1.0 and
Tom> inf-ruby > = 2.0.

Jonas thinks this is best left outside the package.  I disagree
slightly: I think a compromise is best, where the package author can
specify the dependencies but the repository maintainer can override
them.  Since Emacs doesn't provide any of these facilities by
convention, perhaps it's time to set them up now.

Ted> In order to ensure these dependencies are tracked correctly, is there a
Ted> *standard* way in Emacs to test if a library loads and runs some basic
Ted> unit and integration tests correctly?

Tom> No.

Tom> For package.el it would be a bad idea to load all packages.  This is
Tom> slow, and loading a package can have undesirable side effects.

I was thinking of using the emacs interpreter in batch mode to run only
a few tests in series, isolated from the testing agent in a whole new
process.  For the majority of libraries that's enough.

Ted