How to use byteStreamControllerBrandCheckException method in wpt

Best JavaScript code snippet using wpt

readable-stream.js

Source:readable-stream.js

...934    .catch(rethrowAssertionErrorRejection);935  }936  get byobRequest() {937    if (IsReadableByteStreamController(this) === false) {938      throw byteStreamControllerBrandCheckException('byobRequest');939    }940    if (this._byobRequest === undefined && this._pendingPullIntos.length > 0) {941      const firstDescriptor = this._pendingPullIntos[0];942      const view = new Uint8Array(firstDescriptor.buffer,943                                  firstDescriptor.byteOffset + firstDescriptor.bytesFilled,944                                  firstDescriptor.byteLength - firstDescriptor.bytesFilled);945      this._byobRequest = new ReadableStreamBYOBRequest(this, view);946    }947    return this._byobRequest;948  }949  get desiredSize() {950    if (IsReadableByteStreamController(this) === false) {951      throw byteStreamControllerBrandCheckException('desiredSize');952    }953    return ReadableByteStreamControllerGetDesiredSize(this);954  }955  close() {956    if (IsReadableByteStreamController(this) === false) {957      throw byteStreamControllerBrandCheckException('close');958    }959    if (this._closeRequested === true) {960      throw new TypeError('The stream has already been closed; do not close it again!');961    }962    const state = this._controlledReadableStream._state;963    if (state !== 'readable') {964      throw new TypeError(`The stream (in ${state} state) is not in the readable state and cannot be closed`);965    }966    ReadableByteStreamControllerClose(this);967  }968  enqueue(chunk) {969    if (IsReadableByteStreamController(this) === false) {970      throw byteStreamControllerBrandCheckException('enqueue');971    }972    if (this._closeRequested === true) {973      throw new TypeError('stream is closed or draining');974    }975    const state = this._controlledReadableStream._state;976    if (state !== 'readable') {977      throw new TypeError(`The stream (in ${state} state) is not in the readable state and cannot be enqueued to`);978    }979    if (!ArrayBuffer.isView(chunk)) {980      throw new TypeError('You can only enqueue array buffer views when using a ReadableByteStreamController');981    }982    ReadableByteStreamControllerEnqueue(this, chunk);983  }984  error(e) {985    if (IsReadableByteStreamController(this) === false) {986      throw byteStreamControllerBrandCheckException('error');987    }988    const stream = this._controlledReadableStream;989    if (stream._state !== 'readable') {990      throw new TypeError(`The stream is ${stream._state} and so cannot be errored`);991    }992    ReadableByteStreamControllerError(this, e);993  }994  [InternalCancel](reason) {995    if (this._pendingPullIntos.length > 0) {996      const firstDescriptor = this._pendingPullIntos[0];997      firstDescriptor.bytesFilled = 0;998    }999    this._queue = [];1000    this._totalQueuedBytes = 0;1001    return PromiseInvokeOrNoop(this._underlyingByteSource, 'cancel', [reason]);1002  }1003  [InternalPull]() {1004    const stream = this._controlledReadableStream;1005    if (ReadableStreamGetNumReadRequests(stream) === 0) {1006      if (this._totalQueuedBytes > 0) {1007        const entry = this._queue.shift();1008        this._totalQueuedBytes -= entry.byteLength;1009        ReadableByteStreamControllerHandleQueueDrain(this);1010        let view;1011        try {1012          view = new Uint8Array(entry.buffer, entry.byteOffset, entry.byteLength);1013        } catch (viewE) {1014          return Promise.reject(viewE);1015        }1016        return Promise.resolve(CreateIterResultObject(view, false));1017      }1018      const autoAllocateChunkSize = this._autoAllocateChunkSize;1019      if (autoAllocateChunkSize !== undefined) {1020        let buffer;1021        try {1022          buffer = new ArrayBuffer(autoAllocateChunkSize);1023        } catch (bufferE) {1024          return Promise.reject(bufferE);1025        }1026        const pullIntoDescriptor = {1027          buffer,1028          byteOffset: 0,1029          byteLength: autoAllocateChunkSize,1030          bytesFilled: 0,1031          elementSize: 1,1032          ctor: Uint8Array,1033          readerType: 'default'1034        };1035        this._pendingPullIntos.push(pullIntoDescriptor);1036      }1037    } else {1038      assert(this._autoAllocateChunkSize === undefined);1039    }1040    const promise = ReadableStreamAddReadRequest(stream);1041    ReadableByteStreamControllerCallPullIfNeeded(this);1042    return promise;1043  }1044}1045// Abstract operations for the ReadableByteStreamController.1046function IsReadableByteStreamController(x) {1047  if (!typeIsObject(x)) {1048    return false;1049  }1050  if (!Object.prototype.hasOwnProperty.call(x, '_underlyingByteSource')) {1051    return false;1052  }1053  return true;1054}1055function IsReadableStreamBYOBRequest(x) {1056  if (!typeIsObject(x)) {1057    return false;1058  }1059  if (!Object.prototype.hasOwnProperty.call(x, '_associatedReadableByteStreamController')) {1060    return false;1061  }1062  return true;1063}1064function ReadableByteStreamControllerCallPullIfNeeded(controller) {1065  const shouldPull = ReadableByteStreamControllerShouldCallPull(controller);1066  if (shouldPull === false) {1067    return undefined;1068  }1069  if (controller._pulling === true) {1070    controller._pullAgain = true;1071    return undefined;1072  }1073  assert(controller._pullAgain === false);1074  controller._pulling = true;1075  // TODO: Test controller argument1076  const pullPromise = PromiseInvokeOrNoop(controller._underlyingByteSource, 'pull', [controller]);1077  pullPromise.then(1078    () => {1079      controller._pulling = false;1080      if (controller._pullAgain === true) {1081        controller._pullAgain = false;1082        ReadableByteStreamControllerCallPullIfNeeded(controller);1083      }1084    },1085    e => {1086      if (controller._controlledReadableStream._state === 'readable') {1087        ReadableByteStreamControllerError(controller, e);1088      }1089    }1090  )1091  .catch(rethrowAssertionErrorRejection);1092  return undefined;1093}1094function ReadableByteStreamControllerClearPendingPullIntos(controller) {1095  ReadableByteStreamControllerInvalidateBYOBRequest(controller);1096  controller._pendingPullIntos = [];1097}1098function ReadableByteStreamControllerCommitPullIntoDescriptor(stream, pullIntoDescriptor) {1099  assert(stream._state !== 'errored', 'state must not be errored');1100  let done = false;1101  if (stream._state === 'closed') {1102    assert(pullIntoDescriptor.bytesFilled === 0);1103    done = true;1104  }1105  const filledView = ReadableByteStreamControllerConvertPullIntoDescriptor(pullIntoDescriptor);1106  if (pullIntoDescriptor.readerType === 'default') {1107    ReadableStreamFulfillReadRequest(stream, filledView, done);1108  } else {1109    assert(pullIntoDescriptor.readerType === 'byob');1110    ReadableStreamFulfillReadIntoRequest(stream, filledView, done);1111  }1112}1113function ReadableByteStreamControllerConvertPullIntoDescriptor(pullIntoDescriptor) {1114  const bytesFilled = pullIntoDescriptor.bytesFilled;1115  const elementSize = pullIntoDescriptor.elementSize;1116  assert(bytesFilled <= pullIntoDescriptor.byteLength);1117  assert(bytesFilled % elementSize === 0);1118  return new pullIntoDescriptor.ctor(1119      pullIntoDescriptor.buffer, pullIntoDescriptor.byteOffset, bytesFilled / elementSize);1120}1121function ReadableByteStreamControllerEnqueueChunkToQueue(controller, buffer, byteOffset, byteLength) {1122  controller._queue.push({ buffer, byteOffset, byteLength });1123  controller._totalQueuedBytes += byteLength;1124}1125function ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(controller, pullIntoDescriptor) {1126  const elementSize = pullIntoDescriptor.elementSize;1127  const currentAlignedBytes = pullIntoDescriptor.bytesFilled - pullIntoDescriptor.bytesFilled % elementSize;1128  const maxBytesToCopy = Math.min(controller._totalQueuedBytes,1129                                  pullIntoDescriptor.byteLength - pullIntoDescriptor.bytesFilled);1130  const maxBytesFilled = pullIntoDescriptor.bytesFilled + maxBytesToCopy;1131  const maxAlignedBytes = maxBytesFilled - maxBytesFilled % elementSize;1132  let totalBytesToCopyRemaining = maxBytesToCopy;1133  let ready = false;1134  if (maxAlignedBytes > currentAlignedBytes) {1135    totalBytesToCopyRemaining = maxAlignedBytes - pullIntoDescriptor.bytesFilled;1136    ready = true;1137  }1138  const queue = controller._queue;1139  while (totalBytesToCopyRemaining > 0) {1140    const headOfQueue = queue[0];1141    const bytesToCopy = Math.min(totalBytesToCopyRemaining, headOfQueue.byteLength);1142    const destStart = pullIntoDescriptor.byteOffset + pullIntoDescriptor.bytesFilled;1143    ArrayBufferCopy(pullIntoDescriptor.buffer, destStart, headOfQueue.buffer, headOfQueue.byteOffset, bytesToCopy);1144    if (headOfQueue.byteLength === bytesToCopy) {1145      queue.shift();1146    } else {1147      headOfQueue.byteOffset += bytesToCopy;1148      headOfQueue.byteLength -= bytesToCopy;1149    }1150    controller._totalQueuedBytes -= bytesToCopy;1151    ReadableByteStreamControllerFillHeadPullIntoDescriptor(controller, bytesToCopy, pullIntoDescriptor);1152    totalBytesToCopyRemaining -= bytesToCopy;1153  }1154  if (ready === false) {1155    assert(controller._totalQueuedBytes === 0, 'queue must be empty');1156    assert(pullIntoDescriptor.bytesFilled > 0);1157    assert(pullIntoDescriptor.bytesFilled < pullIntoDescriptor.elementSize);1158  }1159  return ready;1160}1161function ReadableByteStreamControllerFillHeadPullIntoDescriptor(controller, size, pullIntoDescriptor) {1162  assert(controller._pendingPullIntos.length === 0 || controller._pendingPullIntos[0] === pullIntoDescriptor);1163  ReadableByteStreamControllerInvalidateBYOBRequest(controller);1164  pullIntoDescriptor.bytesFilled += size;1165}1166function ReadableByteStreamControllerHandleQueueDrain(controller) {1167  assert(controller._controlledReadableStream._state === 'readable');1168  if (controller._totalQueuedBytes === 0 && controller._closeRequested === true) {1169    ReadableStreamClose(controller._controlledReadableStream);1170  } else {1171    ReadableByteStreamControllerCallPullIfNeeded(controller);1172  }1173}1174function ReadableByteStreamControllerInvalidateBYOBRequest(controller) {1175  if (controller._byobRequest === undefined) {1176    return;1177  }1178  controller._byobRequest._associatedReadableByteStreamController = undefined;1179  controller._byobRequest._view = undefined;1180  controller._byobRequest = undefined;1181}1182function ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller) {1183  assert(controller._closeRequested === false);1184  while (controller._pendingPullIntos.length > 0) {1185    if (controller._totalQueuedBytes === 0) {1186      return;1187    }1188    const pullIntoDescriptor = controller._pendingPullIntos[0];1189    if (ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(controller, pullIntoDescriptor) === true) {1190      ReadableByteStreamControllerShiftPendingPullInto(controller);1191      ReadableByteStreamControllerCommitPullIntoDescriptor(controller._controlledReadableStream, pullIntoDescriptor);1192    }1193  }1194}1195function ReadableByteStreamControllerPullInto(controller, view) {1196  const stream = controller._controlledReadableStream;1197  let elementSize = 1;1198  if (view.constructor !== DataView) {1199    elementSize = view.constructor.BYTES_PER_ELEMENT;1200  }1201  const ctor = view.constructor;1202  const pullIntoDescriptor = {1203    buffer: view.buffer,1204    byteOffset: view.byteOffset,1205    byteLength: view.byteLength,1206    bytesFilled: 0,1207    elementSize,1208    ctor,1209    readerType: 'byob'1210  };1211  if (controller._pendingPullIntos.length > 0) {1212    pullIntoDescriptor.buffer = SameRealmTransfer(pullIntoDescriptor.buffer);1213    controller._pendingPullIntos.push(pullIntoDescriptor);1214    // No ReadableByteStreamControllerCallPullIfNeeded() call since:1215    // - No change happens on desiredSize1216    // - The source has already been notified of that there's at least 1 pending read(view)1217    return ReadableStreamAddReadIntoRequest(stream);1218  }1219  if (stream._state === 'closed') {1220    const emptyView = new view.constructor(view.buffer, view.byteOffset, 0);1221    return Promise.resolve(CreateIterResultObject(emptyView, true));1222  }1223  if (controller._totalQueuedBytes > 0) {1224    if (ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(controller, pullIntoDescriptor) === true) {1225      const filledView = ReadableByteStreamControllerConvertPullIntoDescriptor(pullIntoDescriptor);1226      ReadableByteStreamControllerHandleQueueDrain(controller);1227      return Promise.resolve(CreateIterResultObject(filledView, false));1228    }1229    if (controller._closeRequested === true) {1230      const e = new TypeError('Insufficient bytes to fill elements in the given buffer');1231      ReadableByteStreamControllerError(controller, e);1232      return Promise.reject(e);1233    }1234  }1235  pullIntoDescriptor.buffer = SameRealmTransfer(pullIntoDescriptor.buffer);1236  controller._pendingPullIntos.push(pullIntoDescriptor);1237  const promise = ReadableStreamAddReadIntoRequest(stream);1238  ReadableByteStreamControllerCallPullIfNeeded(controller);1239  return promise;1240}1241function ReadableByteStreamControllerRespondInClosedState(controller, firstDescriptor) {1242  firstDescriptor.buffer = SameRealmTransfer(firstDescriptor.buffer);1243  assert(firstDescriptor.bytesFilled === 0, 'bytesFilled must be 0');1244  const stream = controller._controlledReadableStream;1245  while (ReadableStreamGetNumReadIntoRequests(stream) > 0) {1246    const pullIntoDescriptor = ReadableByteStreamControllerShiftPendingPullInto(controller);1247    ReadableByteStreamControllerCommitPullIntoDescriptor(stream, pullIntoDescriptor);1248  }1249}1250function ReadableByteStreamControllerRespondInReadableState(controller, bytesWritten, pullIntoDescriptor) {1251  if (pullIntoDescriptor.bytesFilled + bytesWritten > pullIntoDescriptor.byteLength) {1252    throw new RangeError('bytesWritten out of range');1253  }1254  ReadableByteStreamControllerFillHeadPullIntoDescriptor(controller, bytesWritten, pullIntoDescriptor);1255  if (pullIntoDescriptor.bytesFilled < pullIntoDescriptor.elementSize) {1256    // TODO: Figure out whether we should detach the buffer or not here.1257    return;1258  }1259  ReadableByteStreamControllerShiftPendingPullInto(controller);1260  const remainderSize = pullIntoDescriptor.bytesFilled % pullIntoDescriptor.elementSize;1261  if (remainderSize > 0) {1262    const end = pullIntoDescriptor.byteOffset + pullIntoDescriptor.bytesFilled;1263    const remainder = pullIntoDescriptor.buffer.slice(end - remainderSize, end);1264    ReadableByteStreamControllerEnqueueChunkToQueue(controller, remainder, 0, remainder.byteLength);1265  }1266  pullIntoDescriptor.buffer = SameRealmTransfer(pullIntoDescriptor.buffer);1267  pullIntoDescriptor.bytesFilled -= remainderSize;1268  ReadableByteStreamControllerCommitPullIntoDescriptor(controller._controlledReadableStream, pullIntoDescriptor);1269  ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller);1270}1271function ReadableByteStreamControllerRespondInternal(controller, bytesWritten) {1272  const firstDescriptor = controller._pendingPullIntos[0];1273  const stream = controller._controlledReadableStream;1274  if (stream._state === 'closed') {1275    if (bytesWritten !== 0) {1276      throw new TypeError('bytesWritten must be 0 when calling respond() on a closed stream');1277    }1278    ReadableByteStreamControllerRespondInClosedState(controller, firstDescriptor);1279  } else {1280    assert(stream._state === 'readable');1281    ReadableByteStreamControllerRespondInReadableState(controller, bytesWritten, firstDescriptor);1282  }1283}1284function ReadableByteStreamControllerShiftPendingPullInto(controller) {1285  const descriptor = controller._pendingPullIntos.shift();1286  ReadableByteStreamControllerInvalidateBYOBRequest(controller);1287  return descriptor;1288}1289function ReadableByteStreamControllerShouldCallPull(controller) {1290  const stream = controller._controlledReadableStream;1291  if (stream._state !== 'readable') {1292    return false;1293  }1294  if (controller._closeRequested === true) {1295    return false;1296  }1297  if (controller._started === false) {1298    return false;1299  }1300  if (ReadableStreamHasDefaultReader(stream) && ReadableStreamGetNumReadRequests(stream) > 0) {1301    return true;1302  }1303  if (ReadableStreamHasBYOBReader(stream) && ReadableStreamGetNumReadIntoRequests(stream) > 0) {1304    return true;1305  }1306  if (ReadableByteStreamControllerGetDesiredSize(controller) > 0) {1307    return true;1308  }1309  return false;1310}1311// A client of ReadableByteStreamController may use these functions directly to bypass state check.1312function ReadableByteStreamControllerClose(controller) {1313  const stream = controller._controlledReadableStream;1314  assert(controller._closeRequested === false);1315  assert(stream._state === 'readable');1316  if (controller._totalQueuedBytes > 0) {1317    controller._closeRequested = true;1318    return;1319  }1320  if (controller._pendingPullIntos.length > 0) {1321    const firstPendingPullInto = controller._pendingPullIntos[0];1322    if (firstPendingPullInto.bytesFilled > 0) {1323      const e = new TypeError('Insufficient bytes to fill elements in the given buffer');1324      ReadableByteStreamControllerError(controller, e);1325      throw e;1326    }1327  }1328  ReadableStreamClose(stream);1329}1330function ReadableByteStreamControllerEnqueue(controller, chunk) {1331  const stream = controller._controlledReadableStream;1332  assert(controller._closeRequested === false);1333  assert(stream._state === 'readable');1334  const buffer = chunk.buffer;1335  const byteOffset = chunk.byteOffset;1336  const byteLength = chunk.byteLength;1337  const transferredBuffer = SameRealmTransfer(buffer);1338  if (ReadableStreamHasDefaultReader(stream) === true) {1339    if (ReadableStreamGetNumReadRequests(stream) === 0) {1340      ReadableByteStreamControllerEnqueueChunkToQueue(controller, transferredBuffer, byteOffset, byteLength);1341    } else {1342      assert(controller._queue.length === 0);1343      const transferredView = new Uint8Array(transferredBuffer, byteOffset, byteLength);1344      ReadableStreamFulfillReadRequest(stream, transferredView, false);1345    }1346  } else if (ReadableStreamHasBYOBReader(stream) === true) {1347    // TODO: Ideally in this branch detaching should happen only if the buffer is not consumed fully.1348    ReadableByteStreamControllerEnqueueChunkToQueue(controller, transferredBuffer, byteOffset, byteLength);1349    ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller);1350  } else {1351    assert(IsReadableStreamLocked(stream) === false, 'stream must not be locked');1352    ReadableByteStreamControllerEnqueueChunkToQueue(controller, transferredBuffer, byteOffset, byteLength);1353  }1354}1355function ReadableByteStreamControllerError(controller, e) {1356  const stream = controller._controlledReadableStream;1357  assert(stream._state === 'readable');1358  ReadableByteStreamControllerClearPendingPullIntos(controller);1359  controller._queue = [];1360  ReadableStreamError(stream, e);1361}1362function ReadableByteStreamControllerGetDesiredSize(controller) {1363  return controller._strategyHWM - controller._totalQueuedBytes;1364}1365function ReadableByteStreamControllerRespond(controller, bytesWritten) {1366  bytesWritten = Number(bytesWritten);1367  if (IsFiniteNonNegativeNumber(bytesWritten) === false) {1368    throw new RangeError('bytesWritten must be a finite');1369  }1370  assert(controller._pendingPullIntos.length > 0);1371  ReadableByteStreamControllerRespondInternal(controller, bytesWritten);1372}1373function ReadableByteStreamControllerRespondWithNewView(controller, view) {1374  assert(controller._pendingPullIntos.length > 0);1375  const firstDescriptor = controller._pendingPullIntos[0];1376  if (firstDescriptor.byteOffset + firstDescriptor.bytesFilled !== view.byteOffset) {1377    throw new RangeError('The region specified by view does not match byobRequest');1378  }1379  if (firstDescriptor.byteLength !== view.byteLength) {1380    throw new RangeError('The buffer of view has different capacity than byobRequest');1381  }1382  firstDescriptor.buffer = view.buffer;1383  ReadableByteStreamControllerRespondInternal(controller, view.byteLength);1384}1385// Helper functions for the ReadableStream.1386function streamBrandCheckException(name) {1387  return new TypeError(`ReadableStream.prototype.${name} can only be used on a ReadableStream`);1388}1389// Helper functions for the readers.1390function readerLockException(name) {1391  return new TypeError('Cannot ' + name + ' a stream using a released reader');1392}1393// Helper functions for the ReadableStreamDefaultReader.1394function defaultReaderBrandCheckException(name) {1395  return new TypeError(1396    `ReadableStreamDefaultReader.prototype.${name} can only be used on a ReadableStreamDefaultReader`);1397}1398function defaultReaderClosedPromiseInitialize(reader) {1399  reader._closedPromise = new Promise((resolve, reject) => {1400    reader._closedPromise_resolve = resolve;1401    reader._closedPromise_reject = reject;1402  });1403}1404function defaultReaderClosedPromiseInitializeAsRejected(reader, reason) {1405  reader._closedPromise = Promise.reject(reason);1406  reader._closedPromise_resolve = undefined;1407  reader._closedPromise_reject = undefined;1408}1409function defaultReaderClosedPromiseInitializeAsResolved(reader) {1410  reader._closedPromise = Promise.resolve(undefined);1411  reader._closedPromise_resolve = undefined;1412  reader._closedPromise_reject = undefined;1413}1414function defaultReaderClosedPromiseReject(reader, reason) {1415  assert(reader._closedPromise_resolve !== undefined);1416  assert(reader._closedPromise_reject !== undefined);1417  reader._closedPromise_reject(reason);1418  reader._closedPromise_resolve = undefined;1419  reader._closedPromise_reject = undefined;1420}1421function defaultReaderClosedPromiseResetToRejected(reader, reason) {1422  assert(reader._closedPromise_resolve === undefined);1423  assert(reader._closedPromise_reject === undefined);1424  reader._closedPromise = Promise.reject(reason);1425}1426function defaultReaderClosedPromiseResolve(reader) {1427  assert(reader._closedPromise_resolve !== undefined);1428  assert(reader._closedPromise_reject !== undefined);1429  reader._closedPromise_resolve(undefined);1430  reader._closedPromise_resolve = undefined;1431  reader._closedPromise_reject = undefined;1432}1433// Helper functions for the ReadableStreamDefaultReader.1434function byobReaderBrandCheckException(name) {1435  return new TypeError(1436    `ReadableStreamBYOBReader.prototype.${name} can only be used on a ReadableStreamBYOBReader`);1437}1438// Helper functions for the ReadableStreamDefaultController.1439function defaultControllerBrandCheckException(name) {1440  return new TypeError(1441    `ReadableStreamDefaultController.prototype.${name} can only be used on a ReadableStreamDefaultController`);1442}1443// Helper functions for the ReadableStreamBYOBRequest.1444function byobRequestBrandCheckException(name) {1445  return new TypeError(1446    `ReadableStreamBYOBRequest.prototype.${name} can only be used on a ReadableStreamBYOBRequest`);1447}1448// Helper functions for the ReadableByteStreamController.1449function byteStreamControllerBrandCheckException(name) {1450  return new TypeError(1451    `ReadableByteStreamController.prototype.${name} can only be used on a ReadableByteStreamController`);...

byte-stream-controller.ts

Source:byte-stream-controller.ts

...184   * Returns the current BYOB pull request, or `null` if there isn't one.185   */186  get byobRequest(): ReadableStreamBYOBRequest | null {187    if (!IsReadableByteStreamController(this)) {188      throw byteStreamControllerBrandCheckException('byobRequest');189    }190    if (this._byobRequest === null && this._pendingPullIntos.length > 0) {191      const firstDescriptor = this._pendingPullIntos.peek();192      const view = new Uint8Array(firstDescriptor.buffer,193                                  firstDescriptor.byteOffset + firstDescriptor.bytesFilled,194                                  firstDescriptor.byteLength - firstDescriptor.bytesFilled);195      const byobRequest: ReadableStreamBYOBRequest = Object.create(ReadableStreamBYOBRequest.prototype);196      SetUpReadableStreamBYOBRequest(byobRequest, this, view);197      this._byobRequest = byobRequest;198    }199    return this._byobRequest;200  }201  /**202   * Returns the desired size to fill the controlled stream's internal queue. It can be negative, if the queue is203   * over-full. An underlying byte source ought to use this information to determine when and how to apply backpressure.204   */205  get desiredSize(): number | null {206    if (!IsReadableByteStreamController(this)) {207      throw byteStreamControllerBrandCheckException('desiredSize');208    }209    return ReadableByteStreamControllerGetDesiredSize(this);210  }211  /**212   * Closes the controlled readable stream. Consumers will still be able to read any previously-enqueued chunks from213   * the stream, but once those are read, the stream will become closed.214   */215  close(): void {216    if (!IsReadableByteStreamController(this)) {217      throw byteStreamControllerBrandCheckException('close');218    }219    if (this._closeRequested) {220      throw new TypeError('The stream has already been closed; do not close it again!');221    }222    const state = this._controlledReadableByteStream._state;223    if (state !== 'readable') {224      throw new TypeError(`The stream (in ${state} state) is not in the readable state and cannot be closed`);225    }226    ReadableByteStreamControllerClose(this);227  }228  /**229   * Enqueues the given chunk chunk in the controlled readable stream.230   * The chunk has to be an `ArrayBufferView` instance, or else a `TypeError` will be thrown.231   */232  enqueue(chunk: ArrayBufferView): void;233  enqueue(chunk: ArrayBufferView | undefined): void {234    if (!IsReadableByteStreamController(this)) {235      throw byteStreamControllerBrandCheckException('enqueue');236    }237    assertRequiredArgument(chunk, 1, 'enqueue');238    if (!ArrayBuffer.isView(chunk)) {239      throw new TypeError('chunk must be an array buffer view');240    }241    if (chunk.byteLength === 0) {242      throw new TypeError('chunk must have non-zero byteLength');243    }244    if (chunk.buffer.byteLength === 0) {245      throw new TypeError(`chunk's buffer must have non-zero byteLength`);246    }247    if (this._closeRequested) {248      throw new TypeError('stream is closed or draining');249    }250    const state = this._controlledReadableByteStream._state;251    if (state !== 'readable') {252      throw new TypeError(`The stream (in ${state} state) is not in the readable state and cannot be enqueued to`);253    }254    ReadableByteStreamControllerEnqueue(this, chunk);255  }256  /**257   * Errors the controlled readable stream, making all future interactions with it fail with the given error `e`.258   */259  error(e: any = undefined): void {260    if (!IsReadableByteStreamController(this)) {261      throw byteStreamControllerBrandCheckException('error');262    }263    ReadableByteStreamControllerError(this, e);264  }265  /** @internal */266  [CancelSteps](reason: any): Promise<void> {267    if (this._pendingPullIntos.length > 0) {268      const firstDescriptor = this._pendingPullIntos.peek();269      firstDescriptor.bytesFilled = 0;270    }271    ResetQueue(this);272    const result = this._cancelAlgorithm(reason);273    ReadableByteStreamControllerClearAlgorithms(this);274    return result;275  }276  /** @internal */277  [PullSteps](readRequest: ReadRequest<Uint8Array>): void {278    const stream = this._controlledReadableByteStream;279    assert(ReadableStreamHasDefaultReader(stream));280    if (this._queueTotalSize > 0) {281      assert(ReadableStreamGetNumReadRequests(stream) === 0);282      const entry = this._queue.shift()!;283      this._queueTotalSize -= entry.byteLength;284      ReadableByteStreamControllerHandleQueueDrain(this);285      const view = new Uint8Array(entry.buffer, entry.byteOffset, entry.byteLength);286      readRequest._chunkSteps(view);287      return;288    }289    const autoAllocateChunkSize = this._autoAllocateChunkSize;290    if (autoAllocateChunkSize !== undefined) {291      let buffer: ArrayBuffer;292      try {293        buffer = new ArrayBuffer(autoAllocateChunkSize);294      } catch (bufferE) {295        readRequest._errorSteps(bufferE);296        return;297      }298      const pullIntoDescriptor: DefaultPullIntoDescriptor = {299        buffer,300        byteOffset: 0,301        byteLength: autoAllocateChunkSize,302        bytesFilled: 0,303        elementSize: 1,304        viewConstructor: Uint8Array,305        readerType: 'default'306      };307      this._pendingPullIntos.push(pullIntoDescriptor);308    }309    ReadableStreamAddReadRequest(stream, readRequest);310    ReadableByteStreamControllerCallPullIfNeeded(this);311  }312}313Object.defineProperties(ReadableByteStreamController.prototype, {314  close: { enumerable: true },315  enqueue: { enumerable: true },316  error: { enumerable: true },317  byobRequest: { enumerable: true },318  desiredSize: { enumerable: true }319});320if (typeof Symbol.toStringTag === 'symbol') {321  Object.defineProperty(ReadableByteStreamController.prototype, Symbol.toStringTag, {322    value: 'ReadableByteStreamController',323    configurable: true324  });325}326// Abstract operations for the ReadableByteStreamController.327export function IsReadableByteStreamController(x: any): x is ReadableByteStreamController {328  if (!typeIsObject(x)) {329    return false;330  }331  if (!Object.prototype.hasOwnProperty.call(x, '_controlledReadableByteStream')) {332    return false;333  }334  return true;335}336function IsReadableStreamBYOBRequest(x: any): x is ReadableStreamBYOBRequest {337  if (!typeIsObject(x)) {338    return false;339  }340  if (!Object.prototype.hasOwnProperty.call(x, '_associatedReadableByteStreamController')) {341    return false;342  }343  return true;344}345function ReadableByteStreamControllerCallPullIfNeeded(controller: ReadableByteStreamController): void {346  const shouldPull = ReadableByteStreamControllerShouldCallPull(controller);347  if (!shouldPull) {348    return;349  }350  if (controller._pulling) {351    controller._pullAgain = true;352    return;353  }354  assert(!controller._pullAgain);355  controller._pulling = true;356  // TODO: Test controller argument357  const pullPromise = controller._pullAlgorithm();358  uponPromise(359    pullPromise,360    () => {361      controller._pulling = false;362      if (controller._pullAgain) {363        controller._pullAgain = false;364        ReadableByteStreamControllerCallPullIfNeeded(controller);365      }366    },367    e => {368      ReadableByteStreamControllerError(controller, e);369    }370  );371}372function ReadableByteStreamControllerClearPendingPullIntos(controller: ReadableByteStreamController) {373  ReadableByteStreamControllerInvalidateBYOBRequest(controller);374  controller._pendingPullIntos = new SimpleQueue();375}376function ReadableByteStreamControllerCommitPullIntoDescriptor<T extends ArrayBufferView>(stream: ReadableByteStream,377                                                                                         pullIntoDescriptor: PullIntoDescriptor<T>) {378  assert(stream._state !== 'errored');379  let done = false;380  if (stream._state === 'closed') {381    assert(pullIntoDescriptor.bytesFilled === 0);382    done = true;383  }384  const filledView = ReadableByteStreamControllerConvertPullIntoDescriptor<T>(pullIntoDescriptor);385  if (pullIntoDescriptor.readerType === 'default') {386    ReadableStreamFulfillReadRequest(stream, filledView as unknown as Uint8Array, done);387  } else {388    assert(pullIntoDescriptor.readerType === 'byob');389    ReadableStreamFulfillReadIntoRequest(stream, filledView, done);390  }391}392function ReadableByteStreamControllerConvertPullIntoDescriptor<T extends ArrayBufferView>(pullIntoDescriptor: PullIntoDescriptor<T>): T {393  const bytesFilled = pullIntoDescriptor.bytesFilled;394  const elementSize = pullIntoDescriptor.elementSize;395  assert(bytesFilled <= pullIntoDescriptor.byteLength);396  assert(bytesFilled % elementSize === 0);397  return new pullIntoDescriptor.viewConstructor(398    pullIntoDescriptor.buffer, pullIntoDescriptor.byteOffset, bytesFilled / elementSize) as T;399}400function ReadableByteStreamControllerEnqueueChunkToQueue(controller: ReadableByteStreamController,401                                                         buffer: ArrayBufferLike,402                                                         byteOffset: number,403                                                         byteLength: number) {404  controller._queue.push({ buffer, byteOffset, byteLength });405  controller._queueTotalSize += byteLength;406}407function ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(controller: ReadableByteStreamController,408                                                                     pullIntoDescriptor: PullIntoDescriptor) {409  const elementSize = pullIntoDescriptor.elementSize;410  const currentAlignedBytes = pullIntoDescriptor.bytesFilled - pullIntoDescriptor.bytesFilled % elementSize;411  const maxBytesToCopy = Math.min(controller._queueTotalSize,412                                  pullIntoDescriptor.byteLength - pullIntoDescriptor.bytesFilled);413  const maxBytesFilled = pullIntoDescriptor.bytesFilled + maxBytesToCopy;414  const maxAlignedBytes = maxBytesFilled - maxBytesFilled % elementSize;415  let totalBytesToCopyRemaining = maxBytesToCopy;416  let ready = false;417  if (maxAlignedBytes > currentAlignedBytes) {418    totalBytesToCopyRemaining = maxAlignedBytes - pullIntoDescriptor.bytesFilled;419    ready = true;420  }421  const queue = controller._queue;422  while (totalBytesToCopyRemaining > 0) {423    const headOfQueue = queue.peek();424    const bytesToCopy = Math.min(totalBytesToCopyRemaining, headOfQueue.byteLength);425    const destStart = pullIntoDescriptor.byteOffset + pullIntoDescriptor.bytesFilled;426    CopyDataBlockBytes(pullIntoDescriptor.buffer, destStart, headOfQueue.buffer, headOfQueue.byteOffset, bytesToCopy);427    if (headOfQueue.byteLength === bytesToCopy) {428      queue.shift();429    } else {430      headOfQueue.byteOffset += bytesToCopy;431      headOfQueue.byteLength -= bytesToCopy;432    }433    controller._queueTotalSize -= bytesToCopy;434    ReadableByteStreamControllerFillHeadPullIntoDescriptor(controller, bytesToCopy, pullIntoDescriptor);435    totalBytesToCopyRemaining -= bytesToCopy;436  }437  if (!ready) {438    assert(controller._queueTotalSize === 0);439    assert(pullIntoDescriptor.bytesFilled > 0);440    assert(pullIntoDescriptor.bytesFilled < pullIntoDescriptor.elementSize);441  }442  return ready;443}444function ReadableByteStreamControllerFillHeadPullIntoDescriptor(controller: ReadableByteStreamController,445                                                                size: number,446                                                                pullIntoDescriptor: PullIntoDescriptor) {447  assert(controller._pendingPullIntos.length === 0 || controller._pendingPullIntos.peek() === pullIntoDescriptor);448  ReadableByteStreamControllerInvalidateBYOBRequest(controller);449  pullIntoDescriptor.bytesFilled += size;450}451function ReadableByteStreamControllerHandleQueueDrain(controller: ReadableByteStreamController) {452  assert(controller._controlledReadableByteStream._state === 'readable');453  if (controller._queueTotalSize === 0 && controller._closeRequested) {454    ReadableByteStreamControllerClearAlgorithms(controller);455    ReadableStreamClose(controller._controlledReadableByteStream);456  } else {457    ReadableByteStreamControllerCallPullIfNeeded(controller);458  }459}460function ReadableByteStreamControllerInvalidateBYOBRequest(controller: ReadableByteStreamController) {461  if (controller._byobRequest === null) {462    return;463  }464  controller._byobRequest._associatedReadableByteStreamController = undefined!;465  controller._byobRequest._view = null!;466  controller._byobRequest = null;467}468function ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller: ReadableByteStreamController) {469  assert(!controller._closeRequested);470  while (controller._pendingPullIntos.length > 0) {471    if (controller._queueTotalSize === 0) {472      return;473    }474    const pullIntoDescriptor = controller._pendingPullIntos.peek();475    if (ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(controller, pullIntoDescriptor)) {476      ReadableByteStreamControllerShiftPendingPullInto(controller);477      ReadableByteStreamControllerCommitPullIntoDescriptor(478        controller._controlledReadableByteStream,479        pullIntoDescriptor480      );481    }482  }483}484export function ReadableByteStreamControllerPullInto<T extends ArrayBufferView>(485  controller: ReadableByteStreamController,486  view: T,487  readIntoRequest: ReadIntoRequest<T>488): void {489  const stream = controller._controlledReadableByteStream;490  let elementSize = 1;491  if (view.constructor !== DataView) {492    elementSize = (view.constructor as ArrayBufferViewConstructor<T>).BYTES_PER_ELEMENT;493  }494  const ctor = view.constructor as ArrayBufferViewConstructor<T>;495  const buffer = TransferArrayBuffer(view.buffer);496  const pullIntoDescriptor: BYOBPullIntoDescriptor<T> = {497    buffer,498    byteOffset: view.byteOffset,499    byteLength: view.byteLength,500    bytesFilled: 0,501    elementSize,502    viewConstructor: ctor,503    readerType: 'byob'504  };505  if (controller._pendingPullIntos.length > 0) {506    controller._pendingPullIntos.push(pullIntoDescriptor);507    // No ReadableByteStreamControllerCallPullIfNeeded() call since:508    // - No change happens on desiredSize509    // - The source has already been notified of that there's at least 1 pending read(view)510    ReadableStreamAddReadIntoRequest(stream, readIntoRequest);511    return;512  }513  if (stream._state === 'closed') {514    const emptyView = new ctor(pullIntoDescriptor.buffer, pullIntoDescriptor.byteOffset, 0);515    readIntoRequest._closeSteps(emptyView);516    return;517  }518  if (controller._queueTotalSize > 0) {519    if (ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(controller, pullIntoDescriptor)) {520      const filledView = ReadableByteStreamControllerConvertPullIntoDescriptor<T>(pullIntoDescriptor);521      ReadableByteStreamControllerHandleQueueDrain(controller);522      readIntoRequest._chunkSteps(filledView);523      return;524    }525    if (controller._closeRequested) {526      const e = new TypeError('Insufficient bytes to fill elements in the given buffer');527      ReadableByteStreamControllerError(controller, e);528      readIntoRequest._errorSteps(e);529      return;530    }531  }532  controller._pendingPullIntos.push(pullIntoDescriptor);533  ReadableStreamAddReadIntoRequest<T>(stream, readIntoRequest);534  ReadableByteStreamControllerCallPullIfNeeded(controller);535}536function ReadableByteStreamControllerRespondInClosedState(controller: ReadableByteStreamController,537                                                          firstDescriptor: PullIntoDescriptor) {538  firstDescriptor.buffer = TransferArrayBuffer(firstDescriptor.buffer);539  assert(firstDescriptor.bytesFilled === 0);540  const stream = controller._controlledReadableByteStream;541  if (ReadableStreamHasBYOBReader(stream)) {542    while (ReadableStreamGetNumReadIntoRequests(stream) > 0) {543      const pullIntoDescriptor = ReadableByteStreamControllerShiftPendingPullInto(controller);544      ReadableByteStreamControllerCommitPullIntoDescriptor(stream, pullIntoDescriptor);545    }546  }547}548function ReadableByteStreamControllerRespondInReadableState(controller: ReadableByteStreamController,549                                                            bytesWritten: number,550                                                            pullIntoDescriptor: PullIntoDescriptor) {551  if (pullIntoDescriptor.bytesFilled + bytesWritten > pullIntoDescriptor.byteLength) {552    throw new RangeError('bytesWritten out of range');553  }554  ReadableByteStreamControllerFillHeadPullIntoDescriptor(controller, bytesWritten, pullIntoDescriptor);555  if (pullIntoDescriptor.bytesFilled < pullIntoDescriptor.elementSize) {556    // TODO: Figure out whether we should detach the buffer or not here.557    return;558  }559  ReadableByteStreamControllerShiftPendingPullInto(controller);560  const remainderSize = pullIntoDescriptor.bytesFilled % pullIntoDescriptor.elementSize;561  if (remainderSize > 0) {562    const end = pullIntoDescriptor.byteOffset + pullIntoDescriptor.bytesFilled;563    const remainder = pullIntoDescriptor.buffer.slice(end - remainderSize, end);564    ReadableByteStreamControllerEnqueueChunkToQueue(controller, remainder, 0, remainder.byteLength);565  }566  pullIntoDescriptor.buffer = TransferArrayBuffer(pullIntoDescriptor.buffer);567  pullIntoDescriptor.bytesFilled -= remainderSize;568  ReadableByteStreamControllerCommitPullIntoDescriptor(controller._controlledReadableByteStream, pullIntoDescriptor);569  ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller);570}571function ReadableByteStreamControllerRespondInternal(controller: ReadableByteStreamController, bytesWritten: number) {572  const firstDescriptor = controller._pendingPullIntos.peek();573  const stream = controller._controlledReadableByteStream;574  if (stream._state === 'closed') {575    if (bytesWritten !== 0) {576      throw new TypeError('bytesWritten must be 0 when calling respond() on a closed stream');577    }578    ReadableByteStreamControllerRespondInClosedState(controller, firstDescriptor);579  } else {580    assert(stream._state === 'readable');581    ReadableByteStreamControllerRespondInReadableState(controller, bytesWritten, firstDescriptor);582  }583  ReadableByteStreamControllerCallPullIfNeeded(controller);584}585function ReadableByteStreamControllerShiftPendingPullInto(controller: ReadableByteStreamController): PullIntoDescriptor {586  const descriptor = controller._pendingPullIntos.shift()!;587  ReadableByteStreamControllerInvalidateBYOBRequest(controller);588  return descriptor;589}590function ReadableByteStreamControllerShouldCallPull(controller: ReadableByteStreamController): boolean {591  const stream = controller._controlledReadableByteStream;592  if (stream._state !== 'readable') {593    return false;594  }595  if (controller._closeRequested) {596    return false;597  }598  if (!controller._started) {599    return false;600  }601  if (ReadableStreamHasDefaultReader(stream) && ReadableStreamGetNumReadRequests(stream) > 0) {602    return true;603  }604  if (ReadableStreamHasBYOBReader(stream) && ReadableStreamGetNumReadIntoRequests(stream) > 0) {605    return true;606  }607  const desiredSize = ReadableByteStreamControllerGetDesiredSize(controller);608  assert(desiredSize !== null);609  if (desiredSize! > 0) {610    return true;611  }612  return false;613}614function ReadableByteStreamControllerClearAlgorithms(controller: ReadableByteStreamController) {615  controller._pullAlgorithm = undefined!;616  controller._cancelAlgorithm = undefined!;617}618// A client of ReadableByteStreamController may use these functions directly to bypass state check.619function ReadableByteStreamControllerClose(controller: ReadableByteStreamController) {620  const stream = controller._controlledReadableByteStream;621  if (controller._closeRequested || stream._state !== 'readable') {622    return;623  }624  if (controller._queueTotalSize > 0) {625    controller._closeRequested = true;626    return;627  }628  if (controller._pendingPullIntos.length > 0) {629    const firstPendingPullInto = controller._pendingPullIntos.peek();630    if (firstPendingPullInto.bytesFilled > 0) {631      const e = new TypeError('Insufficient bytes to fill elements in the given buffer');632      ReadableByteStreamControllerError(controller, e);633      throw e;634    }635  }636  ReadableByteStreamControllerClearAlgorithms(controller);637  ReadableStreamClose(stream);638}639function ReadableByteStreamControllerEnqueue(controller: ReadableByteStreamController, chunk: ArrayBufferView) {640  const stream = controller._controlledReadableByteStream;641  if (controller._closeRequested || stream._state !== 'readable') {642    return;643  }644  const buffer = chunk.buffer;645  const byteOffset = chunk.byteOffset;646  const byteLength = chunk.byteLength;647  const transferredBuffer = TransferArrayBuffer(buffer);648  if (ReadableStreamHasDefaultReader(stream)) {649    if (ReadableStreamGetNumReadRequests(stream) === 0) {650      ReadableByteStreamControllerEnqueueChunkToQueue(controller, transferredBuffer, byteOffset, byteLength);651    } else {652      assert(controller._queue.length === 0);653      const transferredView = new Uint8Array(transferredBuffer, byteOffset, byteLength);654      ReadableStreamFulfillReadRequest(stream, transferredView, false);655    }656  } else if (ReadableStreamHasBYOBReader(stream)) {657    // TODO: Ideally in this branch detaching should happen only if the buffer is not consumed fully.658    ReadableByteStreamControllerEnqueueChunkToQueue(controller, transferredBuffer, byteOffset, byteLength);659    ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller);660  } else {661    assert(!IsReadableStreamLocked(stream));662    ReadableByteStreamControllerEnqueueChunkToQueue(controller, transferredBuffer, byteOffset, byteLength);663  }664  ReadableByteStreamControllerCallPullIfNeeded(controller);665}666function ReadableByteStreamControllerError(controller: ReadableByteStreamController, e: any) {667  const stream = controller._controlledReadableByteStream;668  if (stream._state !== 'readable') {669    return;670  }671  ReadableByteStreamControllerClearPendingPullIntos(controller);672  ResetQueue(controller);673  ReadableByteStreamControllerClearAlgorithms(controller);674  ReadableStreamError(stream, e);675}676function ReadableByteStreamControllerGetDesiredSize(controller: ReadableByteStreamController): number | null {677  const stream = controller._controlledReadableByteStream;678  const state = stream._state;679  if (state === 'errored') {680    return null;681  }682  if (state === 'closed') {683    return 0;684  }685  return controller._strategyHWM - controller._queueTotalSize;686}687function ReadableByteStreamControllerRespond(controller: ReadableByteStreamController, bytesWritten: number) {688  bytesWritten = Number(bytesWritten);689  if (!IsFiniteNonNegativeNumber(bytesWritten)) {690    throw new RangeError('bytesWritten must be a finite');691  }692  assert(controller._pendingPullIntos.length > 0);693  ReadableByteStreamControllerRespondInternal(controller, bytesWritten);694}695function ReadableByteStreamControllerRespondWithNewView(controller: ReadableByteStreamController,696                                                        view: ArrayBufferView) {697  assert(controller._pendingPullIntos.length > 0);698  const firstDescriptor = controller._pendingPullIntos.peek();699  if (firstDescriptor.byteOffset + firstDescriptor.bytesFilled !== view.byteOffset) {700    throw new RangeError('The region specified by view does not match byobRequest');701  }702  if (firstDescriptor.byteLength !== view.byteLength) {703    throw new RangeError('The buffer of view has different capacity than byobRequest');704  }705  firstDescriptor.buffer = view.buffer;706  ReadableByteStreamControllerRespondInternal(controller, view.byteLength);707}708export function SetUpReadableByteStreamController(stream: ReadableByteStream,709                                                  controller: ReadableByteStreamController,710                                                  startAlgorithm: () => void | PromiseLike<void>,711                                                  pullAlgorithm: () => Promise<void>,712                                                  cancelAlgorithm: (reason: any) => Promise<void>,713                                                  highWaterMark: number,714                                                  autoAllocateChunkSize: number | undefined) {715  assert(stream._readableStreamController === undefined);716  if (autoAllocateChunkSize !== undefined) {717    assert(NumberIsInteger(autoAllocateChunkSize));718    assert(autoAllocateChunkSize > 0);719  }720  controller._controlledReadableByteStream = stream;721  controller._pullAgain = false;722  controller._pulling = false;723  controller._byobRequest = null;724  // Need to set the slots so that the assert doesn't fire. In the spec the slots already exist implicitly.725  controller._queue = controller._queueTotalSize = undefined!;726  ResetQueue(controller);727  controller._closeRequested = false;728  controller._started = false;729  controller._strategyHWM = highWaterMark;730  controller._pullAlgorithm = pullAlgorithm;731  controller._cancelAlgorithm = cancelAlgorithm;732  controller._autoAllocateChunkSize = autoAllocateChunkSize;733  controller._pendingPullIntos = new SimpleQueue();734  stream._readableStreamController = controller;735  const startResult = startAlgorithm();736  uponPromise(737    promiseResolvedWith(startResult),738    () => {739      controller._started = true;740      assert(!controller._pulling);741      assert(!controller._pullAgain);742      ReadableByteStreamControllerCallPullIfNeeded(controller);743    },744    r => {745      ReadableByteStreamControllerError(controller, r);746    }747  );748}749export function SetUpReadableByteStreamControllerFromUnderlyingSource(750  stream: ReadableByteStream,751  underlyingByteSource: ValidatedUnderlyingByteSource,752  highWaterMark: number753) {754  const controller: ReadableByteStreamController = Object.create(ReadableByteStreamController.prototype);755  let startAlgorithm: () => void | PromiseLike<void> = () => undefined;756  let pullAlgorithm: () => Promise<void> = () => promiseResolvedWith(undefined);757  let cancelAlgorithm: (reason: any) => Promise<void> = () => promiseResolvedWith(undefined);758  if (underlyingByteSource.start !== undefined) {759    startAlgorithm = () => underlyingByteSource.start!(controller);760  }761  if (underlyingByteSource.pull !== undefined) {762    pullAlgorithm = () => underlyingByteSource.pull!(controller);763  }764  if (underlyingByteSource.cancel !== undefined) {765    cancelAlgorithm = reason => underlyingByteSource.cancel!(reason);766  }767  const autoAllocateChunkSize = underlyingByteSource.autoAllocateChunkSize;768  SetUpReadableByteStreamController(769    stream, controller, startAlgorithm, pullAlgorithm, cancelAlgorithm, highWaterMark, autoAllocateChunkSize770  );771}772function SetUpReadableStreamBYOBRequest(request: ReadableStreamBYOBRequest,773                                        controller: ReadableByteStreamController,774                                        view: ArrayBufferView) {775  assert(IsReadableByteStreamController(controller));776  assert(typeof view === 'object');777  assert(ArrayBuffer.isView(view));778  assert(!IsDetachedBuffer(view.buffer));779  request._associatedReadableByteStreamController = controller;780  request._view = view;781}782// Helper functions for the ReadableStreamBYOBRequest.783function byobRequestBrandCheckException(name: string): TypeError {784  return new TypeError(785    `ReadableStreamBYOBRequest.prototype.${name} can only be used on a ReadableStreamBYOBRequest`);786}787// Helper functions for the ReadableByteStreamController.788function byteStreamControllerBrandCheckException(name: string): TypeError {789  return new TypeError(790    `ReadableByteStreamController.prototype.${name} can only be used on a ReadableByteStreamController`);...

Using AI Code Generation

1var test = async_test('Testing byteStreamControllerBrandCheckException method of wpt/resources/testharness.js');2test.step(function()3{4    var byteStreamControllerBrandCheckException = new ReadableStream({5        start(controller) {6            assert_throws(new TypeError(), function() {7                controller.enqueue("a");8            });9            test.done();10        }11    });12    byteStreamControllerBrandCheckException.getReader();13});14function byteStreamControllerBrandCheckException() {15    var rs = new ReadableStream({16        start(controller) {17            assert_throws(new TypeError(), function() {18                controller.enqueue("a");19            });20            done();21        }22    });23    rs.getReader();24}25test(function() {26    var rs = new ReadableStream({27        start(controller) {28            assert_throws(new TypeError(), function() {29                controller.enqueue("a");30            });31            done();32        }33    });34    rs.getReader();35});36promise_test(function() {37    var rs = new ReadableStream({38        start(controller) {39            assert_throws(new TypeError(), function() {40                controller.enqueue("a");41            });42            done();43        }44    });45    return rs.getReader().closed;46});47async_test(function(t) {48    var rs = new ReadableStream({49        start(controller) {50            assert_throws(new TypeError(), function() {51                controller.enqueue("a");52            });53            done();54        }55    });56    rs.getReader().closed.then(t.step_func(function() {57        t.done();58    }));59});60promise_test(function() {61    var rs = new ReadableStream({62        start(controller) {63            assert_throws(new TypeError(), function() {64                controller.enqueue("

Using AI Code Generation

1const test = async () => {2  const { ReadableStream, CountQueuingStrategy } = new WebAssembly.Instance(3    await WebAssembly.instantiateStreaming(fetch("wpt.wasm"), {}),4    {}5  ).exports;6  const stream = new ReadableStream({7    start(controller) {8      controller.enqueue(new Uint8Array([0, 1, 2]));9    },10  });11  const reader = stream.getReader();12  const result = await reader.read();13  const view = new Uint8Array(result.value);14  console.log(view);15};16test();17if (controller[byteStreamControllerBrandCheckException] !== undefined) {18    throw new TypeError();19  }20Error: WebAssembly.instantiateStreaming(): Wasm code generation disallowed by embedder

Using AI Code Generation

1var byteStreamControllerBrandCheckException = wpt.byteStreamControllerBrandCheckException;2var rs = new ReadableStream({3  pull: function(controller) {4    controller.enqueue(1);5  }6});7var reader = rs.getReader();8reader.read().then(function(result) {9  assert_equals(result.value, 1);10  assert_false(result.done);11  var controller = reader.releaseLock();12  assert_throws(byteStreamControllerBrandCheckException, function() {13    controller.enqueue(2);14  });15  return reader.read();16}).then(function(result) {17  assert_equals(result.value, 2);18  assert_false(result.done);19  return reader.read();20}).then(function(result) {21  assert_true(result.done);22}, function(e) {23  assert_unreached(e);24});25test(function() {26  var rs = new ReadableStream({27    pull: function(controller) {28      controller.enqueue(new Uint8Array(1));29    }30  });31  var reader = rs.getReader();32  reader.read().then(function(result) {33    assert_equals(result.value.byteLength, 1);34    assert_false(result.done);35    var controller = reader.releaseLock();36    assert_throws(byteStreamControllerBrandCheckException, function() {37      controller.enqueue(new Uint8Array(1));38    });39    return reader.read();40  }).then(function(result) {41    assert_equals(result.value.byteLength, 1);42    assert_false(result.done);43    return reader.read();44  }).then(function(result) {45    assert_true(result.done);46  }, function(e) {47    assert_unreached(e);48  });49}, 'ReadableStream with byte source: byte stream controller\'s brand check on enqueue()');50test(function() {51  var rs = new ReadableStream({52    pull: function(controller) {53      controller.enqueue(new Uint8Array(1));54    }55  });56  var reader = rs.getReader();57  reader.read().then(function(result) {58    assert_equals(result.value.byteLength, 1);59    assert_false(result.done);60    var controller = reader.releaseLock();61    assert_throws(byteStreamControllerBrandCheckException, function() {

Using AI Code Generation

1test(function() {2  assert_throws(new TypeError(), () => new ByteStreamController({type: "bytes"}));3}, "ByteStreamController constructor should throw when called with a ReadableStream");4function byteStreamControllerBrandCheckException() {5  return new TypeError();6}7function assert_throws(expected, func, description) {8  if (typeof expected === "function") {9    return assert_throws_js(expected, func, description);10  }11  if (typeof expected === "string") {12    return assert_throws_dom(expected, func, description);13  }14  if (typeof expected === "object" && expected !== null) {15    if (expected.name === "TypeError" && expected.message === "ByteStreamController constructor should throw when called with a ReadableStream") {16      return assert_throws_dom("TypeError", func, description);17    }18  }19  throw new Error("assert_throws: invalid expected argument: " + expected);20}21function assert_throws_dom(expected, func, description) {22  if (typeof expected !== "string") {23    throw new Error("assert_throws_dom: invalid expected argument: " + expected);24  }25  var e = assert_throws_js(DOMException, func, description);26  assert_equals(e.name, expected, description);27  return e;28}29function assert_throws_js(expected, func, description) {30  if (typeof expected !== "function") {31    throw new Error("assert_throws_js: invalid expected argument: " + expected);32  }33  var e;34  var message;35  try {36    func();37  } catch (ex) {38    e = ex;39  }40  if (e === undefined) {41    message = "function did not throw an exception";42  } else if (e instanceof expected) {43    return e;44  } else {45    message = "threw " + e + ", expected " + expected.name;46  }47  if (description !== undefined) {48    message = description + ": " + message;49  }50  assert_unreached(message);51}52function assert_unreached(message) {53  assert_true(false, message);54}

Using AI Code Generation

1'use strict';2const byteStreamControllerBrandCheckException = (obj, message) => {3  assert_throws(new TypeError(), () => {4    obj.enqueue('a');5  }, message);6};7test(() => {8  const rs = new ReadableStream({9    start(c) {10      byteStreamControllerBrandCheckException(c, 'controller');11    }12  });13}, 'ReadableStream with byte source: brand check on controller in start method');14test(() => {15  const rs = new ReadableStream({16    pull(c) {17      byteStreamControllerBrandCheckException(c, 'controller');18    }19  });20}, 'ReadableStream with byte source: brand check on controller in pull method');21test(() => {22  const rs = new ReadableStream({23    cancel(c) {24      byteStreamControllerBrandCheckException(c, 'controller');25    }26  });27  rs.cancel();28}, 'ReadableStream with byte source: brand check on controller in cancel method');29test(() => {30  const rs = new ReadableStream({31    start(c) {32      byteStreamControllerBrandCheckException(c.byobRequest, 'byobRequest');33    }34  });35}, 'ReadableStream with byte source: brand check on byobRequest in start method');36test(() => {37  const rs = new ReadableStream({38    pull(c) {39      byteStreamControllerBrandCheckException(c.byobRequest, 'byobRequest');40    }41  });42}, 'ReadableStream with byte source: brand check on byobRequest in pull method');43test(() => {44  const rs = new ReadableStream({45    cancel(c) {46      byteStreamControllerBrandCheckException(c.byobRequest, 'byobRequest');47    }48  });49  rs.cancel();50}, 'ReadableStream with byte source: brand check on byobRequest in cancel method');51test(() => {52  const rs = new ReadableStream({53    start(c) {54      byteStreamControllerBrandCheckException(c.desiredSize, 'desiredSize');55    }56  });57}, 'ReadableStream with byte source: brand check on desiredSize in start method');58test(() => {59  const rs = new ReadableStream({60    pull(c) {61      byteStreamControllerBrandCheckException(c.desiredSize, 'desiredSize');62    }63  });64}, 'ReadableStream with byte source: brand check on desiredSize in pull method');65test(() => {

Using AI Code Generation

1import { byteStreamControllerBrandCheckException } from './resources/test-utils.js';2const controller = new ReadableStream().getReader().read().controller;3byteStreamControllerBrandCheckException(controller);4export function byteStreamControllerBrandCheckException(controller) {5  assert_throws_js(TypeError, () => {6    controller.byobRequest;7  }, 'controller.byobRequest should throw a TypeError exception');8}9export function byteStreamControllerBrandCheckException(controller) {10  assert_throws_js(TypeError, () => {11    controller.byobRequest;12  }, 'controller.byobRequest should throw a TypeError exception');13}14 >  };15>  interface ByteStreamController {16> +  readonly attribute BYOBRequest? byobRequest; 17 >  };18>  interface ReadableStream {19> +  readonly attribute ByteStreamController? controller;

Using AI Code Generation

1var byteStreamControllerBrandCheckException = wpt.byteStreamControllerBrandCheckException;2var byteStreamControllerBrandCheck = wpt.byteStreamControllerBrandCheck;3try {4    byteStreamControllerBrandCheckException(1);5} catch (e) {6    console.log("Exception thrown: " + e);7}8var byteStreamController = new ByteStreamController();9try {10    byteStreamControllerBrandCheckException(byteStreamController);11} catch (e) {12    console.log("Exception thrown: " + e);13}14var byteStreamController = new ByteStreamController();15try {16    byteStreamControllerBrandCheck(byteStreamController);17} catch (e) {18    console.log("Exception thrown: " + e);19}20var byteStreamController = new ByteStreamController();21try {22    console.log(byteStreamControllerBrandCheck(byteStreamController));23} catch (e) {24    console.log("Exception thrown: " + e);25}26var byteStreamController = new ByteStreamController();27try {28    console.log(byteStreamControllerBrandCheck(1));29} catch (e) {30    console.log("Exception thrown: " + e);31}32var byteStreamController = new ByteStreamController();33try {34    console.log(byteStreamControllerBrandCheck("abc"));35} catch (e) {36    console.log("Exception thrown: " + e);37}38var byteStreamController = new ByteStreamController();39try {40    console.log(byteStreamControllerBrandCheck({}));41} catch (e) {42    console.log("Exception thrown: " + e);43}

Using AI Code Generation

1var rs = new ReadableStream({2  start(controller) {3    controller.enqueue(new ArrayBuffer(1));4  }5});6rs.getReader().read().then(({value, done}) => {7  assert_false(done);8  assert_equals(value.byteLength, 1);9});

Using AI Code Generation

1var ReadableStreamBYOBRequest = function (controller) {2    if (!IsReadableByteStreamController(controller)) {3        throw byteStreamControllerBrandCheckException("ReadableStreamBYOBRequest");4    }5    this._associatedReadableByteStreamController = controller;6};7var rs = new ReadableStreamBYOBRequest();

Using AI Code Generation

1import { byteStreamControllerBrandCheckException } from './wpt/resources/testharness.js';2test(() => {3    assert_throws(new RangeError(), () => byteStreamControllerBrandCheckException(undefined));4}, 'ByteStreamControllerBrandCheckException should throw a RangeError when ByteStreamController is passed as undefined');5export function byteStreamControllerBrandCheckException(controller) {6    if (controller === undefined) {7        throw new RangeError();8    }9}10exports.byteStreamControllerBrandCheckException = function(controller) {11    if (controller === undefined) {12        throw new RangeError();13    }14}

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