Pentaho Data Integration includes both unit tests and integration tests (which test cross-module operations).
Unit Tests
To run all unit tests in the project and its sub-modules:
mvn test
To debug a single Java unit test on the default port 5005:
cd core
mvn test -Dtest=<<YourTest>> -Dmaven.surefire.debug
Integration Tests
To run integration tests:
mvn verify -DrunITs
To run a specific integration test:
mvn verify -DrunITs -Dit.test=<<YourIT>>
To run a specific integration test in debug mode on port 5005:
mvn verify -DrunITs -Dit.test=<<YourIT>> -Dmaven.failsafe.debug