add tests
add tests

Signed-off-by: Aidan Oldershaw <30ef7a6e0d016bc846f26d89dacbd23aceded206@pivotal.io>
Co-authored-by: Bohan Chen <c9a015a7f6482b47c219aa2cbd78ba6c88c0a327@pivotal.io>

concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse