CSS Variable LSP (Rust Implementation)

A Language Server Protocol implementation for CSS Variables, written in Rust.

Status: Complete

This is a ground-up Rust rewrite of the TypeScript/Node-based css-variable-lsp, eliminating the Node/npm dependency for the Zed extension.

Features

• CSS parsing for variable definitions and var() usage tracking
• HTML parsing for <style> blocks and inline styles (custom DOM scanner)
• Cascade sorting and specificity calculation
• LSP features: completion, hover, definition, references, rename, diagnostics, document/workspace symbols
• Workspace scanning and color provider (hex/rgb/hsl + named colors)

Building

cargo build --release

Release Assets (Local)

Build and package release assets into dist/ (tar.gz on Unix, zip on Windows):

./scripts/build-release-assets.sh

To build a subset of targets:

./scripts/build-release-assets.sh x86_64-apple-darwin aarch64-apple-darwin

Running

cargo run --release

The LSP server communicates via stdin/stdout using the Language Server Protocol.

Architecture

• main.rs - Entry point, sets up async runtime and LSP server
• lsp_server.rs - LSP protocol handlers (implements tower_lsp::LanguageServer)
• manager.rs - CSS variable manager (stores definitions/usages, DOM trees)
• types.rs - Core data types (CssVariable, CssVariableUsage, Config, etc.)
• parsers/ - CSS and HTML parsing (definitions + var() usages)
• dom_tree.rs - Lightweight HTML scanner for selector matching
• specificity.rs - Specificity calculation and cascade ordering
• workspace.rs - Workspace scanning and file discovery
• runtime_config.rs - CLI/env configuration parsing
• path_display.rs - Path formatting for hover/completion
• color.rs - Color parsing and color provider helpers

Dependencies

• tower-lsp - LSP server framework
• tokio - Async runtime
• globset / walkdir - Workspace scanning
• csscolorparser - Color value parsing
• regex / pathdiff - Parsing helpers and path formatting

License

GPL-3.0