Extend support for nf-test 🚀

[sateeshperi]

There are several ways that the language server might be useful for checking .nf.test files, which is now the testing standard for nf-core and several nextflow pipelines.

Some common things that the server can check for are:

• missing , in multiple assertions in then block
• inputs are not numbered like input[0]
  (will add more)

Would like to know if this is something that the server can check for ?

[maxulysse]

@lukfor any extra ideas?

[bentsherman]

The nf-test scripts would require a custom parser for their syntax, or to re-use the Groovy parser with some custom AST visitors to validate the raw Groovy code

I am considering this, but I am also considering adding a native testing syntax into the Nextflow language based on nf-test. That would also be the proper way to deliver some of the highly requested features for nf-test like better inputs and cloud execution.

So I'm not sure if it's worth all the effort to support nf-test as it currently exists

[sateeshperi]

cc @lukfor