Kw's tests rely on shunit2. The run_tests.sh script automatically detects shunit2 in $PATH in case it is installed in your system. Alternatively, you can have shunit2 source code in tests/ (you can clone it from https://github.com/kward/shunit2).
If you want to run all the tests, try:
./run_tests.sh
List all available test files:
./run_tests.sh list
Or run individual tests with:
./run_tests.sh test TESTFILE1 ...
Kw is already prepared to run tests, build the documentation and check the installation in the github workflow.