Hi Ian,

For our internal dependencies between jbosstools components, we don't use the target-platform. Most of JBoss Tools developers have their dependencies opened as project in the workspace.

for you use-case, you could:
* either import the bundle you depend on in your workspace. The benefit is that you can see and change its code, which can be helpful, or
* create your own target platform and include into it the test bundles

    <location includeAllPlatforms="false" includeMode="slicer" type="InstallableUnit" includeSource="true">
      <repository location="http://download.jboss.org/jbosstools/updates/nightly/integrationtests/4.1.kepler/"/>
      <unit id="org.jboss.tools.tests" version="0.0.0"/>
      <!-- version 0.0.0 will select the best version, so if version changes on site, you won't need to update it there -->
    </location>

Hope this helps. Feel free to ask for more if necessary.
You might also discuss with Max (Andersen) about whether your plugin should already be shaped as a JBoss Tools component and part of a future JBoss Tools release.

--
Mickael Istria
Eclipse developer at JBoss, by Red Hat
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