Cheryl Li focused on improving test quality within the freeCodeCamp/freeCodeCamp repository, specifically addressing a formatting issue in the Curriculum module’s generateSignature test. She identified and resolved a missing space in the expected output, which previously led to unclear test results and potential false negatives. By refining the test expectation using JavaScript and established testing patterns, Cheryl enhanced the reliability of the test suite and contributed to smoother onboarding for new contributors. Her work demonstrated careful debugging and adherence to test-driven development practices, ensuring that curriculum learning outcomes remained accurate and that future regressions in test formatting were prevented.