Test cases format

Could we start defining a format for our test cases? I have attached two 
files illustrating a format that I used for a few test cases while 
writing my prototype. Each test case consists of two parts:

1) A SHACL file including instances
2) A manifest file declaring the tests to run and the expected output

Both files are in Turtle, and the manifest file uses a simple ontology 
that can be found at the end of

http://w3c.github.io/data-shapes/shacl/shacl.shacl.ttl

Of course this is just one possible format among many others, I welcome 
alternatives. Yet I would like to point out that it may be beneficial to 
have an RDF based exchange format of such test cases, because people may 
maintain and publish the test cases together with their data models, as 
linked data.

Regards,
Holger