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import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'import { proxy } from 'valtio'import { watch } from 'valtio/utils'
const sleep = (ms: number) =>  new Promise((resolve) => {    setTimeout(resolve, ms)  })
describe('watch', () => {  beforeEach(() => {    vi.useFakeTimers()  })
  afterEach(() => {    vi.useRealTimers()  })
  it('should re-run for individual proxy updates', async () => {    const reference = proxy({ value: 'Example' })
    const callback = vi.fn()
    watch((get) => {      get(reference)      callback()    })
    expect(callback).toBeCalledTimes(1)    reference.value = 'Update'    await Promise.resolve()    expect(callback).toBeCalledTimes(2)  })  it('should re-run for multiple proxy updates', async () => {    const A = proxy({ value: 'A' })    const B = proxy({ value: 'B' })
    const callback = vi.fn()
    watch((get) => {      get(A)      get(B)      callback()    })
    expect(callback).toBeCalledTimes(1)    A.value = 'B'    await Promise.resolve()    expect(callback).toBeCalledTimes(2)    B.value = 'C'    await Promise.resolve()    expect(callback).toBeCalledTimes(3)  })  it('should cleanup when state updates', async () => {    const reference = proxy({ value: 'Example' })
    const callback = vi.fn()
    watch((get) => {      get(reference)
      return () => {        callback()      }    })
    expect(callback).toBeCalledTimes(0)    reference.value = 'Update'    await Promise.resolve()    expect(callback).toBeCalledTimes(1)  })  it('should cleanup when stopped', () => {    const callback = vi.fn()
    const stop = watch(() => callback)
    expect(callback).toBeCalledTimes(0)    stop()    expect(callback).toBeCalledTimes(1)  })  it('should cleanup internal effects when stopped', () => {    const callback = vi.fn()
    const stop = watch(() => {      watch(() => {        watch(() => {          watch(() => {            watch(() => () => {              callback()            })          })        })      })    })
    expect(callback).toBeCalledTimes(0)    stop()    expect(callback).toBeCalledTimes(1)  })  it('should not loop infinitely with sync (#382)', () => {    const reference = proxy({ value: 'Example' })
    watch(      (get) => {        get(reference)      },      { sync: true },    )
    reference.value = 'Update'  })  it('should support promise watchers', async () => {    const reference = proxy({ value: 'Example' })
    const callback = vi.fn()
    const waitPromise = sleep(10000)    watch(async (get) => {      await waitPromise      get(reference)      callback()    })
    vi.runAllTimers()    await waitPromise
    expect(callback).toBeCalledTimes(1)    // listener will only be attached after one promise callback due to the await stack    await Promise.resolve()    reference.value = 'Update'    // wait for internal promise    await Promise.resolve()    // wait for next promise resolve call due to promise usage inside of callback    await Promise.resolve()    expect(callback).toBeCalledTimes(2)  })
  it('should not subscribe if the watch is stopped before the promise completes', async () => {    const reference = proxy({ value: 'Example' })
    const callback = vi.fn()
    const waitPromise = sleep(10000)    const stop = watch(async (get) => {      await waitPromise      get(reference)      callback()    })    stop()
    vi.runAllTimers()    await waitPromise
    expect(callback).toBeCalledTimes(1)    // listener will only be attached after one promise callback due to the await stack    await Promise.resolve()    reference.value = 'Update'    // wait for internal promise    await Promise.resolve()    // wait for next promise resolve call due to promise usage inside of callback    await Promise.resolve()    expect(callback).toBeCalledTimes(1)  })})