Worked on enhancing the regression testing framework for the OpenLiberty/open-liberty repository by developing a targeted reproduction test for a JPQL CASE parsing bug in EclipseLink. Focused on documenting a scenario where CASE expressions fail to parse if boolean field references omit the entity identifier, the work increased test coverage and improved future debugging efficiency. Leveraged Java and JUnit to expand the regression suite with edge-case tests, ensuring production safety by restricting changes to test code only. Detailed commit messages and explicit bug references were used to aid issue traceability, supporting faster triage and ongoing project maintenance for future development cycles.