language-tools

• Purpose: Svelte Language Tools provides editor integrations and language support for Svelte files, enabling features like syntax highlighting, diagnostics, and autocompletion. It implements the Language Server Protocol (LSP) to power IDE plugins, including the official VSCode extension.

• Target Audience: Developers working with Svelte, particularly those using IDEs like VSCode or other LSP-compatible editors.

• Key Features:

  • Supports .svelte files, which mix HTMLx and JavaScript (with Svelte-specific runtime behavior).
  • Includes a language server (svelte-language-server) for LSP integration.
  • Provides a CLI tool (svelte-check) for type checking and unused CSS detection.
  • Converts Svelte files to TypeScript (svelte2tsx) for better tooling support.

• Framework Support: Primarily focused on Svelte, with deep integration for its compiler and syntax.

• Packages:

  • svelte-language-server: Core LSP implementation.
  • svelte-check: Command-line diagnostics tool.
  • svelte-vscode: Official VSCode extension.
  • svelte2tsx: Transforms Svelte files into TypeScript-compatible code.

• Development: Built with TypeScript and uses pnpm workspaces. Contributions are welcome, and testing is streamlined with a focus on high-level JavaScript objects.

For more details, see the VSCode extension or LSP implementers list.