drop dependency on gtk2, so librsvg can be made a dependency of gtk2

[neverpanic (Clemens Lang)]

librsvg is required for gtk2 applications to show SVG icons. However, librsvg cannot be made a dependency of gtk2, because librsvg depends on gtk2.

However, librsvg seems to build just fine without gtk2, so could you please consider dropping this dependency?

[pixilla (Bradley Giesbrecht)]

Clements, do you have a patch?

[pixilla (Bradley Giesbrecht)]

Clemens, sorry about misspelling your name.

A while back I wanted an svg converter for makeicns and did not want a big build chain. I created a local port (librsvg-minimal) to test a minimal librsvg build.

​librsvg-minimal

If I renamed this port to "librsvg" would this be a suitable replacement for the current librsvg port? I would like to avoid making problems for librsvg dependent ports.

[neverpanic (Clemens Lang)]

Since librsvg's documentation lacks information on why gtk is a dependency I took a look at the configure script and noticed the following:

1. librsvg will not build the GTK+ theme engine, if gtk2 was not found
2. librsvg will not build rsvg-view or rsvg-view-3, if neither gtk2 nor gtk3 were found
3. librsvg will not generate HTML documentation with gtk-doc, if the gtk-doc port is not installed (which can be worked around by declaring a dependency on gtk-doc)

So, dropping the dependency on gtk is not a no-op, but doable imho. We could move the support for gtk into a variant. I'll propose a patch.

[neverpanic (Clemens Lang)]

Patch against the Portfile

[pixilla (Bradley Giesbrecht)]

Clemens, if a depends_lib librsvg is added to the gtk2 port then the new +gtk variant in your librsvg patch can not depend back to gtk2.

[pixilla (Bradley Giesbrecht)]

See r90665