Worked on refactoring and hardening the Temporal API calendar tests within the tc39/test262 repository, focusing on improving both robustness and maintainability. Consolidated and reorganized calendar-related tests to enhance readability and reduce maintenance overhead, while clarifying file naming and test structure for more efficient continuous integration. Implemented strict validation logic in JavaScript to ensure that invalid calendar parameters consistently raise the appropriate RangeError or TypeError, thereby strengthening regression protection for calendar features. Expanded test coverage for Temporal API calendar behaviors, leveraging skills in API development and testing to enable faster detection of issues and support ongoing standards compliance efforts.