Remove LSP specific error codes

[Seelengrab]

JSONRPC.jl/src/core.jl

Lines 18 to 30 in 5adc04b

	elseif ex.code == -32099
	"serverErrorStart"
	elseif ex.code == -32000
	"serverErrorEnd"
	elseif ex.code == -32002
	"ServerNotInitialized"
	elseif ex.code == -32001
	"UnknownErrorCode"
	elseif ex.code == -32800
	"RequestCancelled"
	elseif ex.code == -32801
	"ContentModified"
	else

These are not listed in the JSON-RPC specification under section 5.1, so should probably be removed, as they are in the application defined section and may be different for other servers/clients.

A potential fix would be to have a wrapper error in LanguageServer.jl for the (then missing) custom printing, which would be thrown in places where JSON-RPC errors can occur by catching & rethrowing with the wrapper type. If that is acceptable, I can try to make PRs here and at LanguageServer.jl to implement this.

[pfitzseb]

Those are mentioned in the spec:

-32000 to -32099	Server error	Reserved for implementation-defined server-errors.

We are the server after all and chose to define these errors in our implementation.

[Seelengrab]

Yes, but those are specific to LS.jl, right? Other servers using this may have a different error, so patching this library on a per-server basis seems odd. Moreover, some of these truly are application specific, so hardcoding them seems bad.

I have a patch for this locally without resorting to a new error type, which allows other potential users to also hook into the showerror functionality, allowing this to be decoupled from LS.jl.