I maintain two other projects written in Bash (rbenv and ruby-build). I looked, and couldn't find any suitable testing tools for Bash, so I created Bats.
My criteria for deciding what to work on in the open-source world is: do I need something that doesn't yet exist, or something whose existing implementations are unsuitable? If yes, I try to fill the void as best I can, and package it up nicely so others can use it too.
May be unsuitable for you, as you say -- it looks like it takes less typing/punctuation to write the example tests, though.
It was derived from the Git test harness. I'm already using it for a couple of my projects.
In the case of the small command line applications this is probably the ideal way to test them. Obviously if the application is even remotely complex you will want unit tests too which probably should be implemented in the language (so you can test your procedures directly) but there is a case for integration tests as well.
This is also known as the UNIX philosophy :)
Perhaps you could add this to the list of TAP Producers in testanything.org. Here's the link for the Shell producers entry.
http://testanything.org/wiki/index.php/TAP_Producers#SH_.2F_...
There are two other tools that produce TAP in Shell there, but I haven't used any of them. Before going to sleep I decided give it a try to use Bats in Jenkins. Here's the result:
http://www.kinoshita.eti.br/2011/12/30/testing-shell-code-an...
Thanks for sharing.
Cheers, Bruno P. Kinoshita