Tests

[Prince781]

We need to setup a testing infrastructure. A good setup should capture most use cases of VLS and allow us to quickly detect regressions.

[Prince781]

I guess #32 counts as progress on this issue?

[benwaffle]

It's a starting point. But we haven't written any tests yet.

[Prince781]

I think this would be a good newcomer item. At least writing test cases with syntactically invalid documents would be a good start.