Hi Christian,
The trick with Papyrus Compare is that it no longer uses Collaborative Modeling's build or target platform, but rather its own. It's still embedded in the Collaborative Modeling build however.
The actual target platforms for Papyrus Compare are located under plugins/compare/targetplatforms. You can also check the build locally by building Papyrus Compare only via:
cd plugins/compare
mvn verify
or
mvn verify -Dtarget.stream=nightly
The first one will build against a more stable set of dependencies (I won't call it release, as it includes an integration build for EMF Compare), whereas the second one will build against nightlies. If you only need to add a dependency for your tests, then it should be sufficient to modify compare.tests-nightly and compare.tests-release (Both need to work, but the Collaborative Modeling Gerrit job is currently configured to build the Nightly stream)
You may find some more info on the new wiki page for Papyrus Compare [1]
HTH,
Camille
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