Add Go To Definition Support

[csenn]

No description provided.

[JPercival]

Nice work! At first glance this looks great. We have a release going out today and I don't have time to do a proper review right this second. There's also little bit on reconciliation to do with the work going on here:
https://github.com/DBCG/cql-language-server/tree/feature-more-hover

But I'll try to get it reviewed and merged by the end of the week. :)

[csenn]

Hey @JPercival, wasn't actually ready to PR this back to your master, was actually thinking this was opened to my fork!

But it is essentially done, just wanted to ask you a thing or two first.

This handles the cases of go to definition for functionRefs and expressionRefs in either a) same file or b) different file.

I was also planning on adding better hover support (at least adding resultType info per node), but sounds like you are working on something there?

The main code I have relevant to that would be an alg that 1) using a visitor searches and collects all nodes that overlap a particular cursor location and 2) sorts those by size and takes the smallest one to use as the "current node". It would be pretty easy to use the same code to grab the current hover position node, and then display whatever hover data needed depending on the node type.

And one question I had on this implementation involves this line: https://github.com/DBCG/cql-language-server/pull/60/files#diff-c867af65827372dc9baa79df976936f21b3e71df405cf9dbdb758ec96466d741R215

I'm trying to find whether a functionRef matches a potential functionDef by comparing the definition args with the functionRef Args one by one. Is DataType.isCompatablieWith() good enough? It might not work in certain casting cases I'm thinking, but seems to be close in a lot of the manual testing I did.

[JPercival]

Just a heads up that we're donating this codebase to the cqframework organization. You'll need to update repo URLs accordingly. Apologies for the delay in reviewing this!