Function createUpdater

packages/core/src/hooks/useSpring.test.tsx:421–460

(Component: React.ComponentType<{ args: [any, any?] }>)

}

function createUpdater(Component: React.ComponentType<{ args: [any, any?] }>) {
  let prevElem: React.JSX.Element | undefined
  let result: Awaited<ReturnType<typeof render>> | undefined

  const context: TestContext = {
    async set(values) {
      Object.assign(this, values)
      if (prevElem) {
        await renderWithContext(prevElem)
      }
    },
  }
  // Ensure `context.set` is ignored.
  Object.defineProperty(context, 'set', {
    value: context.set,
    enumerable: false,
  })

  afterEach(() => {
    result = prevElem = undefined
    for (const key in context) {
      delete (context as any)[key]
    }
  })

  async function renderWithContext(elem: React.JSX.Element) {
    const wrapped = (
      <SpringContextProvider {...context}>{elem}</SpringContextProvider>
    )
    if (result) await result.rerender(wrapped)
    else result = await render(wrapped)
    return result
  }

  type Args = Parameters<typeof useSpring>
  const update = (...args: [Args[0], Args[1]?]) =>
    renderWithContext((prevElem = <Component args={args} />))

  return [update, context] as const
}

function testIsRef(ref: SpringRef | null) {
  const props = [