JavaScript

Language server: vtsls

JavaScript shares the same language server as TypeScript (vtsls). It provides type inference even for plain .js files.

Setup

npm install -g @vtsls/language-server

Requirements

• A package.json at project root
• Optional: jsconfig.json for better type inference

With JSDoc Types

vtsls uses JSDoc annotations for type inference in JavaScript files:

/**
 * @param {string} name
 * @returns {Promise<User>}
 */
async function getUser(name) { ... }

krait hover getUser will show the inferred types.

Supported Operations

• find symbol, list symbols, read symbol
• hover — inferred types from JSDoc
• check — JS semantic errors
• edit replace, insert-after, insert-before
• rename