napi-rs/examples/napi/__tests__/generator.spec.ts

import ava from 'ava'

const { Fib, Fib2, Fib3 } = (await import('../index.js')).default

const test = process.env.WASI_TEST ? ava.skip : ava

for (const [index, factory] of [
  () => new Fib(),
  () => Fib2.create(0),
  () => new Fib3(0, 1),
].entries()) {
  test(`should be able to stop a generator #${index}`, (t) => {
    const fib = factory()
    const gen = fib[Symbol.iterator]
    t.is(typeof gen, 'function')
    const iterator = gen()
    t.deepEqual(iterator.next(), {
      done: false,
      value: 1,
    })
    iterator.next()
    iterator.next()
    iterator.next()
    iterator.next()
    t.deepEqual(iterator.next(), {
      done: false,
      value: 8,
    })
    t.deepEqual(iterator.return?.(), {
      done: true,
    })
    t.deepEqual(iterator.next(), {
      done: true,
    })
  })

  test(`should be able to throw to generator #${index}`, (t) => {
    const fib = factory()
    const gen = fib[Symbol.iterator]
    t.is(typeof gen, 'function')
    const iterator = gen()
    t.deepEqual(iterator.next(), {
      done: false,
      value: 1,
    })
    iterator.next()
    iterator.next()
    iterator.next()
    iterator.next()
    t.deepEqual(iterator.next(), {
      done: false,
      value: 8,
    })
    t.throws(() => iterator.throw!(new Error()))
    t.deepEqual(iterator.next(), {
      done: true,
    })
  })
}