IntelliJ content module integrating Grails test runs with the IDE's code-coverage tooling.
Content module org.apache.grails.intellij.module.coverage, shipped as lib/modules/org.apache.grails.intellij.module.coverage.jar.
Its descriptor declares <plugin id="Coverage"/>. This matters: depending on the com.intellij.modules.coverage alias instead caused a NoClassDefFoundError at IDE startup, because the alias does not carry the classes. A content module's <dependencies> must name the class-bearing plugin id.