Attempt non-blocking io

[euclidianAce]

Rather than using sockets, this pr implements a small C module wrapping around poll(2) to check if stdin has any data. This is preferential to sockets since a suprising amount of clients don't actually support using a socket and only use stdio.

Additionally this implements a very rough outline of an event-loop/async work-queue where documents can cancel type checking on themselves if they've been updated before the check completes. This gives a massive speed boost to textDocument/didChange so I've also reenabled it. (Previously we only checked on textDocument/didSave since typechecking is quite expensive)

closes #3

also a windows implementation will have to be figured out since poll(2) is a unix thing

[svermeulen]

I'd like to use this, but am unclear on how poll.c is being compiled. How is the tealls.poll module being added to lua here?

[euclidianAce]

luarocks make should build the c module and copy the already built lua files to the correct place (to do an in tree build, use luarocks init to make a local ./luarocks that works on a local ./lua_modules) also note that luarocks has no teal integration so you'll have to do cyan build && ./luarocks make to do a full build

A couple notes: I've been pretty busy and haven't looked at this for a bit. So keep in mind this is a pretty rough draft, and if I recall correctly the event loop is pretty eager to just spin the cpu.

[svermeulen]

Thanks, I have it building and running now :)

I was getting errors of the form:

no type information for required module: 'dkjson'
no type information for required module: 'lfs'

But was able to avoid these by adding dkjson.d.tl and lfs.d.tl files to the project. Do you have a better way of providing type definitions for dependencies?

[euclidianAce]

You can find type definitions for some lua modules in the teal-types repo here. We don't have a great way of distributing them so for now you'll just have to manually download them and add them somewhere to your LUA_PATH

[svermeulen]

Just want to mention that for some reason I am finding that some RPCs are not received when using this MR. I can clearly see in the neovim LSP log that they are being sent, but they do not appear in the teal-language-server log anywhere

[svermeulen]

Ok figured out my issue! Turns out you need to explicitly set stdin to be unbuffered like this:

io.stdin:setvbuf  'no'
io.stdout:setvbuf 'no'

Otherwise, poll.c will think that there is no data available when there is