16 - until

[guoqiangui]

// 你的答案
<script setup lang="ts">
import { ref, watch, type Ref } from 'vue'

const count = ref(0)

/**
 * Implement the until function
 */

function until<T>(initial: Ref<T>) {
  function toBe(value: T): Promise<void> {
    return new Promise((resolve) => {
      const stop = watch(initial, (newVal) => {
        if (newVal === value) {
          resolve()
          stop()
        }
      })
    })
  }

  return {
    toBe,
  }
}

async function increase() {
  count.value = 0
  setInterval(() => {
    count.value++
  }, 1000)
  await until(count).toBe(3)
  console.log(count.value === 3) // Make sure the output is true
}
</script>

<template>
  <p @click="increase">Increase</p>
</template>