You must write commit logs and Pull Requests in English. Because most users could read English, but can't read most of other languages at all.
There are tests for ci-phpunit-test: https://github.com/kenjis/ci-app-for-ci-phpunit-test/tree/master/application/tests
Please write test code for your code and send Pull Request to the repository above. I don't accept your Pull Request if the code coverage is down.
Please update documentation if it is needed.