| 353 | }); |
| 354 | Object.assign(ReadableStreamAsyncIteratorPrototype, { |
| 355 | next() { |
| 356 | const internal = ReadableStreamAsyncIteratorBrand.get(this); |
| 357 | const reader = internal.reader; |
| 358 | const nextSteps = () => { |
| 359 | if (internal.isFinished) |
| 360 | return Promise.resolve({ value:undefined, done:true }); |
| 361 | assert(reader.stream !== undefined); |
| 362 | const promiseRecord = createPromise(); |
| 363 | const readRequest = { |
| 364 | chunkSteps: chunk => resolvePromise(promiseRecord, chunk), |
| 365 | closeSteps: () => { |
| 366 | ReadableStreamDefaultReaderRelease(reader); |
| 367 | resolvePromise(promiseRecord, ReadableStreamAsyncIteratorBrand.token); |
| 368 | }, |
| 369 | errorSteps: e => { |
| 370 | ReadableStreamDefaultReaderRelease(reader); |
| 371 | rejectPromise(promiseRecord, e); |
| 372 | } |
| 373 | }; |
| 374 | ReadableStreamDefaultReaderRead(reader, readRequest); |
| 375 | return promiseRecord.promise.then( |
| 376 | value => { |
| 377 | internal.ongoingPromise = null; |
| 378 | if (value === ReadableStreamAsyncIteratorBrand.token) { |
| 379 | internal.isFinished = true; |
| 380 | return { value: undefined, done: true }; |
| 381 | } |
| 382 | return { value, done: false }; |
| 383 | }, |
| 384 | reason => { |
| 385 | internal.ongoingPromise = null; |
| 386 | internal.isFinished = true; |
| 387 | throw reason; |
| 388 | } |
| 389 | ); |
| 390 | }; |
| 391 | internal.ongoingPromise = internal.ongoingPromise |
| 392 | ? internal.ongoingPromise.then(nextSteps, nextSteps) |
| 393 | : nextSteps(); |
| 394 | return internal.ongoingPromise; |
| 395 | }, |
| 396 | return(value) { |
| 397 | const internal = ReadableStreamAsyncIteratorBrand.get(this); |
| 398 | const reader = internal.reader; |