VitestでIn-source testing

setup

code:vitest.config.ts

/// <reference types="vitest" />

import { defineConfig } from 'vite'

export default defineConfig({

test: {

},

})

tsconfig.ts

code:ts

{

"compilerOptions": {

"types": [

"vitest/importMeta" ←これ

]

}

}

code: src/index.ts

// the implementation

export function add(...args: number[]) {

return args.reduce((a, b) => a + b, 0)

}

// in-source test suites

if (import.meta.vitest) {

const { it, expect } = import.meta.vitest

it('add', () => {

expect(add()).toBe(0)

expect(add(1)).toBe(1)

expect(add(1, 2, 3)).toBe(6)

})

}