Make StringResponse handler's roles more obvious

[ches]

This is an incremental refactoring in response to #330 and the discussion that spawned it: #328 (comment)

This does not attempt to solve some broader design issues discussed in #330, it’s just a small localized change to separate the logic for the very different types of requests that StringResponse can be returned for, so it's more obvious that this handler has these different roles. This is in part to help factor out the direct usage of the editor to finish #328. I've made these private functions for now, they're not really handler functions for discrete ENSIME server response message types like the rest of the formal ProtocolHandler interface. They will might eventually fit logically somewhere else.

As I've mentioned elsewhere, I don't really understand the purpose of the :EnDocUri command, it used to print the documentation URL in Vim's message area—which I don't see as useful—but even that is broken on current master (the command actually causes an exception). My guess is that the intent was that it could be useful as a function instead of command, allowing users to do something custom with the URL as a function result. As-is I don't yet see how to cleanly change it to work that way, it would have to be made synchronous. So with this change, I have un-documented the command but left some implementation in place with a TODO (and it no longer causes an exception, just basically a no-op). I could just go all the way and completely remove the command and that handling code right now, WDYT?

[ktonga]

LGTM

[ktonga]

Let's merge it so you can finish with #328

[ches]

Thanks, I guess I need to LGTM myself since I don't know if anyone else is actively reviewing these days 😄

About to step AFK, should be able to wrap up #328 tomorrow.

[ches]

LGTM

[ktonga]

I thought it was configured to need just one LGTM

[ktonga]

The check seems to be not working

[ches]

I thought so too… I'm not going to like this thing if it's broken…

[ktonga]

Re: Doc URI:

I think, if it is possible, it would be nice to add an optional arg to :EnDoc which should act as action. Missing arg means browse (open in browser) and any provided value should be the name of a function that takes a string (the resultant URI) as parameter and performs whatever action is desired. :EnDocUri should be removed.

Open doc as usual:
:EnDoc

Perform custom action with URI:
:EnDoc ShowMessage

Somewhere in the vimrc:

function! ShowMessage(msg)
    echom a:msg
endfunction

[ktonga]

LGTM