Re: [gentoo-dev] USE=desktop-file request

[Rich Freeman <rich0@gentoo.org>]

On Wed, Jan 6, 2016 at 2:47 PM, tot-to <gentoo-dev.list@tot-to.com> wrote:
>
> It would be great to make the intallation of desktop-files optional,
> but I mostly concerned about the dependency on
> dev-util/desktop-file-utils...
>
> I think such dependency should be either removed, because it's not
> really required or at least be optional.

Most of the packages you referenced inherit the gnome2 eclass, which
inherits the xdg eclass, which adds a DEPEND on desktop-file-utils.

Technically that should mean that it is fine to uninstall
desktop-file-utils after building most of these packages, because it
is only needed at build time.  However, I imagine that if an xdg
eclass function is called which uses these utilities the package build
will fail if you just stick it in package.provided.

If this were purely about installing the desktop files themselves I'd
say to just use the install mask.  I think you could debate whether it
is OK to pull in desktop-file-utils.  That package is just 4 binaries
and their manpages/docs, and of course the runtime dependency of glib.

I'm not sure it is really worth trying to control this via a USE flag
for such a light dependency.  However, strictly speaking this is an
optional build-time dependency, so it probably could be controlled by
flag.  I'm not so keen on making the build-time behavior automagic
based on whether the package happens to be installed and then spamming
elog on every package that uses the xdg eclass to let you know that
you could manually install that package to get your desktop files
back.

I'd have to check but I suspect that portage hangs onto build-time
dependencies by default, probably so that you're not uninstalling them
and reinstalling them anytime you do anything.  Strictly speaking,
however, it would be safe to depclean anything that is only a
build-time dependency (with the understanding that you're going to be
rebuilding it every time it is needed).

--
Rich