Shade plugin: Shade more than one artifact

Hi there,

first, apologies, if I am on the wrong list for this topic, maybe there is
a more specific list, so feel free to point me towards it.

I am currently trying to persuade the shade plugin to actually shade more
than one artifact. My goal is to create two different test jars. One, which
contains only the needed infrastructure to use in other projects and
another one, that includes all the tests of the current project, so I can
take that jar, unpack it in another project and run all the tests in the
scope of that project (this is used for a plugin the main project, to make
sure, that this plugin does not accidentally remove features needed for
normal functioning). The plugin cannot be merged or created as a sub-module
of the main project, from which I want to create the jars.

My current (non-working) workflow is to create two jars using the
maven-jar-plugin and let the shade plugin do its work, which it does only
with the default jar.

My current workaround is to have a default mvn profile which creates the
slim test jar and another one, which creates the fat test jar - however I
would like to built both at the same time and deploy them.

The pom.xml from my current workaround can be found at
https://github.com/spinscale/elasticsearch/blob/build/test-jar-profiles/pom.xml#L1501-L1632

I'd love to get some feedback if this is possible at all using the shade
plugin, or if my approach is bad and I am supposed to do something
completely different.

Thanks a lot and have a nice day!

--Alex