Swift-MesonLSP

A reimplementation of my Meson language server in Swift.

Current feature set

• Hovering (Documentation often copied verbatim/minimally modified from mesonbuild, CC BY-SA 4.0, same for the entire Sources/MesonDocs directory due to ShareAlike)
• Symbol resolving
• Jump-To-Definition
• Jump-To-Subdir
• A basic set of diagnostics
• Formatting
• Document symbols
• Autocompletion (Somewhat working)
• Inlay hints
• Highlighting
• Automatic subproject/wrap downloads
• Code actions
• Renaming

Limitations

• set_variable/get_variable with non-constant variable name will fail in more complex cases. See here for working patterns
• subdir with non-constant subdir name will fail in more complex cases. See here for working patterns
• Type deduction is not 100% correct yet
• Type definitions may have minor errors regarding:
  • Is this argument optional?
  • What is the type of the argument?

Why a reimplementation?

The first version, written in Vala, had some code maintenance problems because basically everything was done in one file. I had the choice between untangling that mess or rewriting it as cleanly as possible. I have chosen the latter because I wanted to learn Swift.

Installation

Install the language server

Easy way

• For Fedora, a COPR is provided: https://copr.fedorainfracloud.org/coprs/jcwasmx86/Swift-MesonLSP/
• For Arch, you can use the repo from AUR
• For Ubuntu 18.04,20.04,22.04 and Debian Bullseye, Bookworm, Sid you can use: https://github.com/JCWasmx86/swift-mesonlsp-apt-repo
• For Ubuntu 22.04, MacOS 12 and Windows, you can download binaries from the release section: https://github.com/JCWasmx86/Swift-MesonLSP/releases/latest

Compile from source

git clone https://github.com/JCWasmx86/Swift-MesonLSP
cd Swift-MesonLSP
swift build -c release --static-swift-stdlib
sudo cp .build/release/Swift-MesonLSP /usr/local/bin

Or you can use podman (Maybe even docker, but only podman is tested):

DOCKER_BUILDKIT=1 podman build --file docker/Dockerfile --output out --no-cache .
# If you want to use Ubuntu 22.04 as docker image
DOCKER_BUILDKIT=1 podman build --file docker/Dockerfile.ubuntu --output out --no-cache .
# If you want to use Ubuntu 18.04 as docker image
DOCKER_BUILDKIT=1 podman build --file docker/Dockerfile.ubuntu1804 --output out --no-cache .
# If you want to use Ubuntu 20.04 as docker image
DOCKER_BUILDKIT=1 podman build --file docker/Dockerfile.ubuntu2004 --output out --no-cache .

This will place a file "Fedora37.zip" (Or Ubuntu22.04.zip) in the directory out. It contains two statically linked binaries. Copy Swift-MesonLSP to /usr/local/bin.

A debug build is provided, too. Just rename it from Swift-MesonLSP.debug to Swift-MesonLSP and copy it to the right destination.

Connect with your editor

VSCode

Install this fork of vscode-meson: https://github.com/JCWasmx86/vscode-meson

GNOME Builder 45 and GNOME Builder Nightly

You have to do nothing. The editor already has the support code for Swift-MesonLSP. All you have to do is installing the language server.

Kate

Add this JSON to ~/.config/kate/lspclient/settings.json:

{
  "servers": {
    "meson": {
      "command": [
        "Swift-MesonLSP",
        "--lsp"
      ],
      "rootIndicationFileNames": [
        "meson.build",
        "meson_options.txt"
      ],
      "url": "https://github.com/JCWasmx86/Swift-MesonLSP",
      "highlightingModeRegex": "^Meson$"
    }
  }
}

After that, a dialog should be shown asking you to confirm that the language server may be started.

neovim

Add this JSON to :CocConfig:

{
    "languageserver": {
        "meson": {
            "command": "Swift-MesonLSP",
            "args": ["--lsp"],
            "rootPatterns": ["meson.build"],
            "filetypes": ["meson"]
        }
    }
}

Want to contribute?

Take an item from the TODO list in PROGRESS.md and work on it. Feel free to join the matrix channel #mesonlsp:matrix.org

Dependencies

• ConsoleKit - APIs for creating interactive CLI tools. (Used the loghandler from there to have nice logs)
• Perfect-INIParser - A lightweight INI file parser in Server Side Swift
• sourcekit-lsp - Language Server Protocol implementation for Swift and C-based languages. (I used the JSONRPC definitions from them)
• SWCompression - A Swift framework for working with compression, archives and containers.
• swift-argument-parser - Straightforward, type-safe argument parsing for Swift
• swift-crypto - Open-source implementation of a substantial portion of the API of Apple CryptoKit suitable for use on Linux platforms.
• Swifter - Tiny http server engine written in Swift programming language.
• swift-log - A Logging API for Swift
• swift-backtrace - Backtraces for Swift on Linux and Windows
• SwiftTreeSitter - Swift API for the tree-sitter incremental parsing system
• tree-sitter-meson - A tree-sitter grammar for meson.build files. Forked and enhanced by me.

Projects I tested the language server with

• Working fine:
  • Fractal
  • GitG
  • GLib
  • GNOME Builder
  • GNOME Builder Plugins
  • GTK
  • libswiftdemangle
  • Mesa
  • QEMU
  • rustc-demangle
  • Systemd
  • GStreamer
• Somewhat flaky to unusable
  • HelenOS
  • picolibc
  • DPDK