WIT IDL for VSCode

This package is a Visual Studio Code extension to recognize and highlight the WebAssembly Interface Type (WIT) Interface Definition Language (IDL). It can also be used as a bundle in TextMate.

The description of the WIT format can be found at: https://github.com/WebAssembly/component-model/blob/main/design/mvp/WIT.md

Features

This extension provides:

• Basic syntax highlighting of ".wit" files.
• Snippets for worlds and interfaces.
• Basic markdown highlighting in comments.
• Simple list-based autocomplete.
• WIT Syntax Checking: Validate WIT files for common syntax errors and provide diagnostics.

Syntax Validation and Error Display

The extension provides comprehensive WIT syntax validation with error display in VS Code's PROBLEMS pane:

Automatic Validation

• On File Save: Automatically validates WIT files when saved
• On File Open: Validates WIT files when opened in the editor
• Real-time Feedback: Errors appear immediately in the PROBLEMS pane

Manual Commands

• WIT: Check Syntax (Ctrl+Shift+P → "WIT: Check Syntax")

  • Validates the currently active WIT file
  • Shows detailed error information in notifications
  • Displays errors in the PROBLEMS pane

• WIT: Check Syntax in Workspace (Ctrl+Shift+P → "WIT: Check Syntax in Workspace")

  • Validates all WIT files in the workspace
  • Shows progress notification during validation
  • Provides summary of results
  • Creates detailed report in output channel

Error Information

When validation fails, the extension displays:

• Error location: Precise line and column numbers
• Error message: Detailed description of the syntax error
• Context: Additional information about the error
• Related information: Links to relevant documentation or context

PROBLEMS Pane Integration

• Errors appear automatically in VS Code's PROBLEMS pane
• Click on any error to jump directly to the problematic line
• Errors are cleared automatically when files are fixed or closed
• Supports multiple files with errors simultaneously

Code Completion

The extension offers intelligent code completion for WIT files:

• Context-aware suggestions: Provides completion items based on the current context
• Keyword snippets: Includes common WIT keywords and constructs
• Custom snippets: User-defined snippets for faster coding

Command Palette Integration

Easily access extension features through the Command Palette:

• WIT: Check Syntax: Validate the current file's syntax
• WIT: Check Syntax in Workspace: Validate all WIT files in the workspace
• WIT: Show Output Channel: Display the extension's output channel

Installation

From Marketplace

This extension is available on:

• Visual Studio Marketplace: For VS Code users

  • Install directly from VS Code: Search for "WIT IDL" in the Extensions view
  • Or visit: https://marketplace.visualstudio.com/items?itemName=bytecodealliance.wit-idl

• Open VSX Registry: For VSCodium and other compatible editors

  • Install from Open VSX: https://open-vsx.org/extension/bytecodealliance/wit-idl
  • Or install via CLI: ovsx get bytecodealliance.wit-idl

Prerequisites

This extension includes a WebAssembly component that requires the following tools for building:

• Rust (with cargo): Required for building the WebAssembly module
• wasm-pack v0.13.1: Used specifically for the wit-bindgen-wasm subproject

You can install these dependencies by running:

# Install Rust (if not already installed)
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

# Run the setup script to install build tools
npm run setup-wasm

From Source

To install from source, follow these steps:

• Clone the repository: git clone https://github.com/bytecodealliance/vscode-wit.git && cd vscode-wit
• Install build dependencies: npm run setup-wasm
• Run npm commands to install: npm ci && npm run install-extension

Publishing (for maintainers)

This extension is automatically published to both Visual Studio Marketplace and Open VSX Registry through GitHub Actions when a release is created.

Required secrets:

• PAT_VSCE: Personal Access Token for Visual Studio Marketplace
• OVSX_PAT: Personal Access Token for Open VSX Registry

To obtain an Open VSX token:

1. Create an account at https://open-vsx.org/
2. Generate a Personal Access Token from your account settings
3. Add the token as OVSX_PAT in the repository secrets