toBeUndefined()

Wait until the value is undefined.

Signature

toBeUndefined(options?: UntilToMatchOptions): Promise<T>

Parameters

options

• Type: UntilToMatchOptions
• Required: No

Options for timeout behavior.

Returns

A Promise that resolves to undefined when the value is undefined.

Examples

Basic Usage

import until from 'untiljs'

let config = { debug: true }
setTimeout(() => { config = undefined as any }, 500)

const result = await until(() => config).toBeUndefined()
console.log(result) // undefined

Waiting for Deletion

import until from 'untiljs'

let cache: Record<string, any> = { key: 'value' }

function clearCache() {
  cache = undefined as any
}

setTimeout(clearCache, 1000)

await until(() => cache).toBeUndefined()
console.log('Cache cleared')

With Timeout

import until from 'untiljs'

let config = { debug: true }

const result = await until(() => config).toBeUndefined({ timeout: 5000 })

With Vue

import { ref } from 'vue'
import until from 'untiljs'

const config = ref<Config | undefined>({ debug: true })

async function reset() {
  config.value = undefined
  await until(config).toBeUndefined()
  console.log('Config reset')
}

See Also

• toBeNull()
• toBeTruthy()
• not.toBeUndefined()