Function waitForOutput

packages/dev-proxy/src/cli.spec.ts:54–90

(
  child: DevProxyCliProcess,
  output: () => string,
  expectedOutput: string,
)

}

const waitForOutput = (
  child: DevProxyCliProcess,
  output: () => string,
  expectedOutput: string,
) => new Promise<void>((resolve, reject) => {
  let timeout: ReturnType<typeof setTimeout>

  function cleanup() {
    clearTimeout(timeout)
    child.stdout.off('data', onData)
    child.stderr.off('data', onData)
    child.off('exit', onExit)
  }

  function onData() {
    if (!output().includes(expectedOutput))
      return

    cleanup()
    resolve()
  }

  function onExit(code: number | null, signal: NodeJS.Signals | null) {
    cleanup()
    reject(new Error(`dev-proxy exited before writing "${expectedOutput}" with code ${code} and signal ${signal}. Output:\n${output()}`))
  }

  timeout = setTimeout(() => {
    cleanup()
    reject(new Error(`Timed out waiting for "${expectedOutput}". Output:\n${output()}`))
  }, 3000)

  child.stdout.on('data', onData)
  child.stderr.on('data', onData)
  child.once('exit', onExit)
  onData()
})

const fetchTextWithRetry = async (url: string) => {
  let lastError: unknown