RustyLR LSP

RustyLR LSP provides rich language support for RustyLR grammar files (*.rustylr and rustylr.rs). Language features are powered by the rustylr lsp language server.

Install it from the Visual Studio Marketplace, or run this command from VS Code Quick Open:

ext install ehwan.rustylr-lsp

Features

• Diagnostics & Error Reporting: Real-time diagnostics for grammar syntax errors, unused symbols, conflict resolutions, and more.
• Go to Definition: Quickly navigate to rule definitions, terminal declarations, and precedence rules.
• Find References: Find all occurrences and usages of terminals, non-terminals, and precedence symbols.
• Syntax Highlighting (Semantic Tokens): Distinct, theme-aligned colors for terminal names, non-terminal rules, directives, bindings, location bindings (@loc), and variables ($var).
• Formatting: Automatic document formatter that standardizes directives, separates rules, and indents rule lines and reduce-action bodies.
• Code Actions (Quick Fixes): Fast diagnostic suppression actions using the %allow directive.
• Hover tooltips: Documented explanations and types for terminal tokens, non-terminal rules, keywords, and patterns.
• Inlay Hints: Inline type annotations and reduce action indicators.
• Auto-Completion: Intelligent suggestions for directives, symbols, locations, variables, and diagnostics.

Extension Settings

This extension contributes the following settings to control the language server behavior:

• rustylr.server.command: Path to the rustylr executable. Leave empty to automatically detect or run from Cargo.
• rustylr.server.args: Arguments passed to the language server command. Leave empty for automatic detection; when pointing directly at rustylr, use ["lsp"].
• rustylr.server.cwd: Working directory for the language server.
• rustylr.server.documentPatterns: Additional file globs handled by the RustyLR language server.
• rustylr.semanticTokens.enabled: Toggle semantic token syntax highlighting.

Installation & Requirements

This extension requires the RustyLR Language Server, which is built into the rustylr executable and started with rustylr lsp. The extension checks the server's major.minor version before startup and allows patch-version differences.

1. Install the VSCode Extension

Install RustyLR LSP from the Marketplace, or use VS Code Quick Open:

ext install ehwan.rustylr-lsp

2. Install the Language Server

You can install the RustyLR executable globally using Cargo:

cargo install rustylr

When installed this way, Cargo places the rustylr executable in Cargo's binary directory (commonly ~/.cargo/bin on Unix-like systems). Make sure that directory is in your PATH; the extension looks for rustylr on PATH when rustylr.server.command is empty.

The extension checks the rustylr executable version before starting the language server. If the installed version is not compatible with this extension release, it shows the exact versioned install command for the expected server version.

If you use a custom path instead of automatic detection:

{
  "rustylr.server.command": "/path/to/rustylr",
  "rustylr.server.args": ["lsp"]
}

3. Open a RustyLR Grammar File

Open any *.rustylr file or a file named rustylr.rs. The extension starts rustylr lsp automatically and enables diagnostics, completion, hover, formatting, go to definition, find references, inlay hints, semantic tokens, and quick fixes.

4. For RustyLR Workspace Contributors

If you are developing or contributing to the RustyLR repository:

• The extension will automatically detect built binaries in the target/debug or target/release folders of your repository root.
• If no prebuilt binary is found, it falls back to running the server dynamically using cargo run --package rustylr -- lsp.

Marketplace Status

This extension is published as RustyLR LSP and remains in preview while the RustyLR language server continues to evolve.