Janet LSP
A Language Server (LSP) for the Janet programming language.
Overview
The goal of this project is to provide an augmented editor/tooling experience for Janet, via a self-contained, Language Server Protocol-compliant language server (which is itself implemented in Janet!).
Current features include:
- Auto-completion based on symbols in the Janet Standard Library and defined in user code
- On-hover definition of symbols as returned by
(doc ,symbol)
- Inline compiler errors
- Pop-up signature help
Planned features include:
- Jump to definition/implementation
- Find references from definition/implementation
- Refactoring helps
- Symbol renaming helps
Possible (but de-prioritized) features include:
- Syntax highlighting for Janet via semantic tokens
Desirable, but possibly more complicated/difficult features include:
- Stand-alone (i.e. non-Editor-dependent) usage via API/CLI
Caveats
- MacOS support is mostly untested (but as far as I know there shouldn't be major differences).
- The only editor integration currently tested against is Visual Studio Code.
- I've never written a language server before, so I don't really know what I'm doing. Help me, if you'd like!
Clients (i.e. Editors)
Currently, the only editor tested and known working with Janet LSP is Visual Studio Code, which you can try/take advantage of by installing the Janet++ extension from the VS Code marketplace.
Other editors that implement LSP client protocols, either built-in or through editor extensions, include:
- Emacs
- vim/neovim
- Sublime Text
- Helix
- Kakoune
If you get Janet LSP working with any of these options, please let me know!
Getting Started (for Development)
Clone this project and Build the stand-alone binary and .jimage file
$ git clone https://github.com/CFiggers/janet-lsp
$ cd janet-lsp
$ jpm deps
$ jpm build
Both a stand-alone (albeit dynamically linked) binary executable and a .jimage (Janet image) file will be generated.
Installing
After running the commands above, the following command will copy the janet-lsp
binary to a location that can be executed via the command line.
$ jpm install
Debug Console
Starting in version 0.0.3, you can start a debug console by passing --console
to any invocation of Janet LSP, including any of the following:
$ ./build/janet-lsp --console
OR
$ janet ./build/janet-lsp.jimage --console
OR
$ janet ./src/main.janet --console
In this mode, the LSP will launch a simple RPC server that listens on port 8037 (by default, configurable with the --debug-port
flag). Janet LSPs with version >= 0.0.3
will check for a listening server on port 8037 (or the port specified by --debug-port
) and, if found, transmit anything sent through the (logging/log)
function to be printed out by the debug console.
In the future, the debug console may function as a networked REPL allowing commands to be sent to the running language server process (but right now it functions in listen-only mode).
Contributions
Issues and Pull Requests welcome.
Prior Art
This project is a hard fork from (with much appreciation to) JohnDoneth/janet-language-server, which is Copyright (c) 2022 JohnDoneth and contributors.