16 - until

[Gilfoyle-sy]

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

const count = ref(0)

/**
 * Implement the until function
 */

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

  return {
    toBe,
  }
}

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

<template>
  <p @click="increase">Increase</p>
  <p>count: {{ count }}</p>
</template>