Function feed

packages/opencode/test/cli/run/stream.transport.test.ts:104–141

(returnValue: R = StreamClosed)

const StreamClosed = undefined as never

function feed<T, R = never>(returnValue: R = StreamClosed) {
  const list: T[] = []
  let done = false
  let wake: (() => void) | undefined

  const wrapped = (async function* (): AsyncGenerator<T, R, unknown> {
    while (!done || list.length > 0) {
      if (list.length === 0) {
        await new Promise<void>((resolve) => {
          wake = resolve
        })
        continue
      }

      const next = list.shift()
      if (!next) {
        continue
      }

      yield next
    }
    return returnValue as R
  })()

  return {
    stream: wrapped,
    push(value: T) {
      list.push(value)
      wake?.()
      wake = undefined
    },
    close() {
      done = true
      wake?.()
      wake = undefined
    },
  }
}

function eventFeed() {
  return feed<SdkEvent>()