Re: Dependency graph for Emacs Lisp files

[phillip.lord@russet.org.uk (Phillip Lord)]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> phillip.lord@russet.org.uk (Phillip Lord) writes:
>
>> `make check` currently uses the a fudge based on name matching between
>> tests and source files, but it missed any other form of
>> dependency. Having something better would be nice. I think autoloads
>> dependencies might be more thatn 3% of the problem, though, but if you
>> add a mechanism based on `require` then an autoload dependency could be
>> added later.
>
> autoloads generally don't lead to compilation breakages, do they?  You
> can't autoload a macro meaningfully, or a variable...

Lots of dependencies happen by side-effect, though.


(defun fred-function-1())
(defmacro fred-macro(&rest body))
(provide 'fred)


(autoload "fred-function-1" "fred")
(defun george-function-1()
   (fred-function-1)
   (fred-macro (george-function-2)))
(provide 'george)


Besides, if this is to work for more than compilation (i.e. testing)
it's not just about compilation breakage. Functional breakage also
counts.


>> Rather than creating "dependency.el", though, why not create an
>> includeable Makefile? That way you might need to delete anything, just
>> let Make to it's dependency thing.
>
> I am no make expert at all, so I don't quite know what that would look
> like.
>
> My thought was that if file A.el depended on file B.el, and B.el has
> changed, then there would just be a step in the compilation process that
> deleted both A.elc and B.elc, and then the rest of the process would
> continue on as before.
>
> (We need to delete B.elc because otherwise `(require B)' in A.el would
> load the old B.elc, and A.el might be byte-compiled before B.el.)


a.elc: a.el b.elc
b.elc: b.el


Changes to b.el would now force a.elc recompilation. If this were in
place then the current name based fudge for tests should work.

a-test.log: a.test.el a.elc


Of course, I have put this forward in simple terms -- Emacs makefile are
in multiple directories, with dependencies between directories, with a
complicated bootstrap, so the reality would be rather more brutal.

Phil