msw/test/browser/rest-api/response/body/body-binary.test.ts

import fs from 'node:fs'
import { test, expect } from '../../../playwright.extend'

test('responds with a given binary body', async ({ loadExample, fetch }) => {
  await loadExample(new URL('./body-binary.mocks.ts', import.meta.url))

  const res = await fetch('/images/abc-123')
  const status = res.status()
  const body = await res.body()

  const expectedBuffer = fs.readFileSync(
    new URL('../../../../fixtures/image.jpg', import.meta.url),
  )

  expect(status).toBe(200)
  expect(res.fromServiceWorker()).toBe(true)
  expect(new Uint8Array(body)).toEqual(new Uint8Array(expectedBuffer))
})