There is a number of tests that cover how jpackage bundles modular apps:

test/jdk/tools/jpackage/share/ModulePathTest.java
test/jdk/tools/jpackage/share/ModulePathTest2.java
test/jdk/tools/jpackage/share/ModulePathTest3.java
test/jdk/tools/jpackage/share/NoMPathRuntimeTest.java

The latter three each have a single test case. Test cases were distributed across these tests in this way due to the limitations of jpackage's test lib. These limitations don't exist anymore. Consolidate all these tests into a single one to reduce code duplication.