This ticket relates to
THORN-1309 which was closed due to being out of date. The issue is still present on 2.5.0.
When JaCoCo doesn't output coverage data to a file until the JVM shuts down. If the JVM is terminated forcefully this coverage output will never happen. Looking at org.wildfly.swarm.tools.exec.SwarmProcess it does seem as though the process is simply being forcabley shutdown (it was suggested on
THORN-1309 that on windows the behaviour is slightly different than on Linux) I'm using Windows 10 and the process does seem to be terminating by force, and so no coverage data is actually ever output.