How to use ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue method in wpt

Best JavaScript code snippet using wpt

readable-internals.ts

Source:readable-internals.ts

1/**2 * streams/readable-internals - internal types and functions for readable streams3 * Part of Stardazed4 * (c) 2018-Present by @zenmumbler5 * https://github.com/stardazed/sd-streams6 */7import * as ws from "./writable-internals";8import * as shared from "./shared-internals";9import * as q from "./queue-mixin";10// ReadableStreamDefaultController11export const controlledReadableStream_ = Symbol("controlledReadableStream_");12export const pullAlgorithm_ = Symbol("pullAlgorithm_");13export const cancelAlgorithm_ = Symbol("cancelAlgorithm_");14export const strategySizeAlgorithm_ = Symbol("strategySizeAlgorithm_");15export const strategyHWM_ = Symbol("strategyHWM_");16export const started_ = Symbol("started_");17export const closeRequested_ = Symbol("closeRequested_");18export const pullAgain_ = Symbol("pullAgain_");19export const pulling_ = Symbol("pulling_");20export const cancelSteps_ = Symbol("cancelSteps_");21export const pullSteps_ = Symbol("pullSteps_");22// ReadableByteStreamController23export const autoAllocateChunkSize_ = Symbol("autoAllocateChunkSize_");24export const byobRequest_ = Symbol("byobRequest_");25export const controlledReadableByteStream_ = Symbol("controlledReadableByteStream_");26export const pendingPullIntos_ = Symbol("pendingPullIntos_");27// ReadableStreamDefaultReader28export const closedPromise_ = Symbol("closedPromise_");29export const ownerReadableStream_ = Symbol("ownerReadableStream_");30export const readRequests_ = Symbol("readRequests_");31export const readIntoRequests_ = Symbol("readIntoRequests_");32// ReadableStreamBYOBRequest33export const associatedReadableByteStreamController_ = Symbol("associatedReadableByteStreamController_");34export const view_ = Symbol("view_");35// ReadableStreamBYOBReader36// ReadableStream37export const reader_ = Symbol("reader_");38export const readableStreamController_ = Symbol("readableStreamController_");39export type StartFunction<OutputType> = (controller: SDReadableStreamControllerBase<OutputType>) => void | PromiseLike<void>;40export type StartAlgorithm = () => Promise<void> | void;41export type PullFunction<OutputType> = (controller: SDReadableStreamControllerBase<OutputType>) => void | PromiseLike<void>;42export type PullAlgorithm<OutputType> = (controller: SDReadableStreamControllerBase<OutputType>) => PromiseLike<void>;43export type CancelAlgorithm = (reason?: shared.ErrorResult) => Promise<void>;44// ----45export interface SDReadableStreamControllerBase<OutputType> {46	readonly desiredSize: number | null;47	close(): void;48	error(e?: shared.ErrorResult): void;49	[cancelSteps_](reason: shared.ErrorResult): Promise<void>;50	[pullSteps_](forAuthorCode: boolean): Promise<IteratorResult<OutputType>>;51}52export interface SDReadableStreamBYOBRequest {53	readonly view: ArrayBufferView;54	respond(bytesWritten: number): void;55	respondWithNewView(view: ArrayBufferView): void;56	[associatedReadableByteStreamController_]: SDReadableByteStreamController | undefined;57	[view_]: ArrayBufferView | undefined;58}59interface ArrayBufferViewCtor {60	new(buffer: ArrayBufferLike, byteOffset?: number, byteLength?: number): ArrayBufferView;61}62export interface PullIntoDescriptor {63	readerType: "default" | "byob";64	ctor: ArrayBufferViewCtor;65	buffer: ArrayBufferLike;66	bufferByteLength: number;67	byteOffset: number;68	byteLength: number;69	bytesFilled: number;70	elementSize: number;71}72export interface SDReadableByteStreamController extends SDReadableStreamControllerBase<ArrayBufferView>, q.ByteQueueContainer {73	readonly byobRequest: SDReadableStreamBYOBRequest | undefined;74	enqueue(chunk: ArrayBufferView): void;75	[autoAllocateChunkSize_]: number | undefined; // A positive integer, when the automatic buffer allocation feature is enabled. In that case, this value specifies the size of buffer to allocate. It is undefined otherwise.76	[byobRequest_]: SDReadableStreamBYOBRequest | undefined; // A ReadableStreamBYOBRequest instance representing the current BYOB pull request77	[cancelAlgorithm_]: CancelAlgorithm; // A promise-returning algorithm, taking one argument (the cancel reason), which communicates a requested cancelation to the underlying source78	[closeRequested_]: boolean; // A boolean flag indicating whether the stream has been closed by its underlying byte source, but still has chunks in its internal queue that have not yet been read79	[controlledReadableByteStream_]: SDReadableStream<ArrayBufferView>; // The ReadableStream instance controlled80	[pullAgain_]: boolean; // A boolean flag set to true if the streamâs mechanisms requested a call to the underlying byte sourceâs pull() method to pull more data, but the pull could not yet be done since a previous call is still executing81	[pullAlgorithm_]: PullAlgorithm<ArrayBufferView>; // A promise-returning algorithm that pulls data from the underlying source82	[pulling_]: boolean; // A boolean flag set to true while the underlying byte sourceâs pull() method is executing and has not yet fulfilled, used to prevent reentrant calls83	[pendingPullIntos_]: PullIntoDescriptor[]; // A List of descriptors representing pending BYOB pull requests84	[started_]: boolean; // A boolean flag indicating whether the underlying source has finished starting85	[strategyHWM_]: number; // A number supplied to the constructor as part of the streamâs queuing strategy, indicating the point at which the stream will apply backpressure to its underlying byte source86}87export interface SDReadableStreamDefaultController<OutputType> extends SDReadableStreamControllerBase<OutputType>, q.QueueContainer<OutputType> {88	enqueue(chunk?: OutputType): void;89	[controlledReadableStream_]: SDReadableStream<OutputType>;90	[pullAlgorithm_]: PullAlgorithm<OutputType>;91	[cancelAlgorithm_]: CancelAlgorithm;92	[strategySizeAlgorithm_]: QueuingStrategySize<OutputType>;93	[strategyHWM_]: number;94	[started_]: boolean;95	[closeRequested_]: boolean;96	[pullAgain_]: boolean;97	[pulling_]: boolean;98}99// ----100export interface SDReadableStreamReader<OutputType> {101	readonly closed: Promise<void>;102	cancel(reason: shared.ErrorResult): Promise<void>;103	releaseLock(): void;104	[ownerReadableStream_]: SDReadableStream<OutputType> | undefined;105	[closedPromise_]: shared.ControlledPromise<void>;106}107export interface ReadRequest<V> extends shared.ControlledPromise<V> {108	forAuthorCode: boolean;109}110export declare class SDReadableStreamDefaultReader<OutputType> implements SDReadableStreamReader<OutputType> {111	constructor(stream: SDReadableStream<OutputType>);112	readonly closed: Promise<void>;113	cancel(reason: shared.ErrorResult): Promise<void>;114	releaseLock(): void;115	read(): Promise<IteratorResult<OutputType | undefined>>;116	[ownerReadableStream_]: SDReadableStream<OutputType> | undefined;117	[closedPromise_]: shared.ControlledPromise<void>;118	[readRequests_]: ReadRequest<IteratorResult<OutputType>>[];119}120export declare class SDReadableStreamBYOBReader implements SDReadableStreamReader<ArrayBufferView> {121	constructor(stream: SDReadableStream<ArrayBufferView>);122	readonly closed: Promise<void>;123	cancel(reason: shared.ErrorResult): Promise<void>;124	releaseLock(): void;125	read(view: ArrayBufferView): Promise<IteratorResult<ArrayBufferView>>;126	[ownerReadableStream_]: SDReadableStream<ArrayBufferView> | undefined;127	[closedPromise_]: shared.ControlledPromise<void>;128	[readIntoRequests_]: ReadRequest<IteratorResult<ArrayBufferView>>[];129}130// ----131export interface GenericTransformStream<InputType, OutputType> {132	readable: SDReadableStream<OutputType>;133	writable: ws.WritableStream<InputType>;134}135export type ReadableStreamState = "readable" | "closed" | "errored";136export declare class SDReadableStream<OutputType> {137	constructor(underlyingSource?: UnderlyingSource<OutputType>, strategy?: QueuingStrategy<OutputType>);138	readonly locked: boolean;139	cancel(reason?: shared.ErrorResult): Promise<void>;140	getReader(): SDReadableStreamReader<OutputType>;141	getReader(options: { mode: "byob" }): SDReadableStreamBYOBReader;142	tee(): SDReadableStream<OutputType>[];143	pipeThrough<ResultType>(transform: GenericTransformStream<OutputType, ResultType>, options?: StreamPipeOptions): SDReadableStream<ResultType>;144	pipeTo(dest: ws.WritableStream<OutputType>, options?: StreamPipeOptions): Promise<void>;145	[shared.state_]: ReadableStreamState;146	[shared.storedError_]: shared.ErrorResult;147	[reader_]: SDReadableStreamReader<OutputType> | undefined;148	[readableStreamController_]: SDReadableStreamControllerBase<OutputType>;149}150// ---- Stream151export function initializeReadableStream<OutputType>(stream: SDReadableStream<OutputType>) {152	stream[shared.state_] = "readable";153	stream[reader_] = undefined;154	stream[shared.storedError_] = undefined;155	stream[readableStreamController_] = undefined!; // mark slot as used for brand check156}157export function isReadableStream(value: unknown): value is SDReadableStream<any> {158	if (typeof value !== "object" || value === null) {159		return false;160	}161	return readableStreamController_ in value;162}163export function isReadableStreamLocked<OutputType>(stream: SDReadableStream<OutputType>) {164	return stream[reader_] !== undefined;165}166export function readableStreamGetNumReadIntoRequests<OutputType>(stream: SDReadableStream<OutputType>) {167	const reader = stream[reader_] as SDReadableStreamBYOBReader;168	if (reader === undefined) {169		return 0;170	}171	return reader[readIntoRequests_].length;172}173export function readableStreamGetNumReadRequests<OutputType>(stream: SDReadableStream<OutputType>) {174	const reader = stream[reader_] as SDReadableStreamDefaultReader<OutputType>;175	if (reader === undefined) {176		return 0;177	}178	return reader[readRequests_].length;179}180export function readableStreamCreateReadResult<T>(value: T, done: boolean, forAuthorCode: boolean): IteratorResult<T> {181	const prototype = forAuthorCode ? Object.prototype : null;182	const result = Object.create(prototype);183	result.value = value;184	result.done = done;185	return result;186}187export function readableStreamAddReadIntoRequest(stream: SDReadableStream<ArrayBufferView>, forAuthorCode: boolean) {188	// Assert: ! IsReadableStreamBYOBReader(stream.[[reader]]) is true.189	// Assert: stream.[[state]] is "readable" or "closed".190	const reader = stream[reader_] as SDReadableStreamBYOBReader;191	const conProm = shared.createControlledPromise<IteratorResult<ArrayBufferView>>() as ReadRequest<IteratorResult<ArrayBufferView>>;192	conProm.forAuthorCode = forAuthorCode;193	reader[readIntoRequests_].push(conProm);194	return conProm.promise;195}196export function readableStreamAddReadRequest<OutputType>(stream: SDReadableStream<OutputType>, forAuthorCode: boolean) {197	// Assert: ! IsReadableStreamDefaultReader(stream.[[reader]]) is true.198	// Assert: stream.[[state]] is "readable".199	const reader = stream[reader_] as SDReadableStreamDefaultReader<OutputType>;200	const conProm = shared.createControlledPromise<IteratorResult<OutputType>>() as ReadRequest<IteratorResult<OutputType>>;201	conProm.forAuthorCode = forAuthorCode;202	reader[readRequests_].push(conProm);203	return conProm.promise;204}205export function readableStreamHasBYOBReader<OutputType>(stream: SDReadableStream<OutputType>) {206	const reader = stream[reader_];207	return isReadableStreamBYOBReader(reader);208}209export function readableStreamHasDefaultReader<OutputType>(stream: SDReadableStream<OutputType>) {210	const reader = stream[reader_];211	return isReadableStreamDefaultReader(reader);212}213export function readableStreamCancel<OutputType>(stream: SDReadableStream<OutputType>, reason: shared.ErrorResult) {214	if (stream[shared.state_] === "closed") {215		return Promise.resolve(undefined);216	}217	if (stream[shared.state_] === "errored") {218		return Promise.reject(stream[shared.storedError_]);219	}220	readableStreamClose(stream);221	const sourceCancelPromise = stream[readableStreamController_][cancelSteps_](reason);222	return sourceCancelPromise.then(_ => undefined);223}224export function readableStreamClose<OutputType>(stream: SDReadableStream<OutputType>) {225	// Assert: stream.[[state]] is "readable".226	stream[shared.state_] = "closed";227	const reader = stream[reader_];228	if (reader === undefined) {229		return;230	}231	reader[closedPromise_].resolve();232	reader[closedPromise_].promise.catch(() => {});233	if (isReadableStreamDefaultReader(reader)) {234		for (const readRequest of reader[readRequests_]) {235			readRequest.resolve(readableStreamCreateReadResult(undefined, true, readRequest.forAuthorCode));236		}237		reader[readRequests_] = [];238	}239}240export function readableStreamError<OutputType>(stream: SDReadableStream<OutputType>, error: shared.ErrorResult) {241	if (stream[shared.state_] !== "readable") {242		throw new RangeError("Stream is in an invalid state");243	}244	stream[shared.state_] = "errored";245	stream[shared.storedError_] = error;246	const reader = stream[reader_];247	if (reader === undefined) {248		return;249	}250	reader[closedPromise_].reject(error);251	if (isReadableStreamDefaultReader(reader)) {252		for (const readRequest of reader[readRequests_]) {253			readRequest.reject(error);254		}255		reader[readRequests_] = [];256	}257	else {258		// Assert: IsReadableStreamBYOBReader(reader).259		const readIntoRequests = (reader as SDReadableStreamBYOBReader)[readIntoRequests_];260		for (const readIntoRequest of readIntoRequests) {261			readIntoRequest.reject(error);262		}263		(reader as SDReadableStreamBYOBReader)[readIntoRequests_] = [];264	}265}266// ---- Readers267export function isReadableStreamDefaultReader(reader: unknown): reader is SDReadableStreamDefaultReader<any> {268	if (typeof reader !== "object" || reader === null) {269		return false;270	}271	return readRequests_ in reader;272}273export function isReadableStreamBYOBReader(reader: unknown): reader is SDReadableStreamBYOBReader {274	if (typeof reader !== "object" || reader === null) {275		return false;276	}277	return readIntoRequests_ in reader;278}279export function readableStreamReaderGenericInitialize<OutputType>(reader: SDReadableStreamReader<OutputType>, stream: SDReadableStream<OutputType>) {280	reader[ownerReadableStream_] = stream;281	stream[reader_] = reader;282	const streamState = stream[shared.state_];283	reader[closedPromise_] = shared.createControlledPromise<void>();284	if (streamState === "readable") {285		// leave as is286	}287	else if (streamState === "closed") {288		reader[closedPromise_].resolve(undefined);289	}290	else {291		reader[closedPromise_].reject(stream[shared.storedError_]);292		reader[closedPromise_].promise.catch(() => {});293	}294}295export function readableStreamReaderGenericRelease<OutputType>(reader: SDReadableStreamReader<OutputType>) {296	// Assert: reader.[[ownerReadableStream]] is not undefined.297	// Assert: reader.[[ownerReadableStream]].[[reader]] is reader.298	const stream = reader[ownerReadableStream_];299	if (stream === undefined) {300		throw new TypeError("Reader is in an inconsistent state");301	}302	if (stream[shared.state_] === "readable") {303		// code moved out304	}305	else {306		reader[closedPromise_] = shared.createControlledPromise<void>();307	}308	reader[closedPromise_].reject(new TypeError());309	reader[closedPromise_].promise.catch(() => {});310	stream[reader_] = undefined;311	reader[ownerReadableStream_] = undefined;312}313export function readableStreamBYOBReaderRead(reader: SDReadableStreamBYOBReader, view: ArrayBufferView, forAuthorCode = false) {314	const stream = reader[ownerReadableStream_]!;315	// Assert: stream is not undefined.316	317	if (stream[shared.state_] === "errored") {318		return Promise.reject(stream[shared.storedError_]);319	}320	return readableByteStreamControllerPullInto(stream[readableStreamController_] as SDReadableByteStreamController, view, forAuthorCode);321}322export function readableStreamDefaultReaderRead<OutputType>(reader: SDReadableStreamDefaultReader<OutputType>, forAuthorCode = false): Promise<IteratorResult<OutputType | undefined>> {323	const stream = reader[ownerReadableStream_]!;324	// Assert: stream is not undefined.325	if (stream[shared.state_] === "closed") {326		return Promise.resolve(readableStreamCreateReadResult(undefined, true, forAuthorCode));327	}328	if (stream[shared.state_] === "errored") {329		return Promise.reject(stream[shared.storedError_]);330	}331	// Assert: stream.[[state]] is "readable".332	return stream[readableStreamController_][pullSteps_](forAuthorCode);333}334export function readableStreamFulfillReadIntoRequest<OutputType>(stream: SDReadableStream<OutputType>, chunk: ArrayBufferView, done: boolean) {335	const reader = stream[reader_] as SDReadableStreamBYOBReader;336	const readIntoRequest = reader[readIntoRequests_].shift()!; // <-- length check done in caller337	readIntoRequest.resolve(readableStreamCreateReadResult(chunk, done, readIntoRequest.forAuthorCode));338}339export function readableStreamFulfillReadRequest<OutputType>(stream: SDReadableStream<OutputType>, chunk: OutputType, done: boolean) {340	const reader = stream[reader_] as SDReadableStreamDefaultReader<OutputType>;341	const readRequest = reader[readRequests_].shift()!; // <-- length check done in caller342	readRequest.resolve(readableStreamCreateReadResult(chunk, done, readRequest.forAuthorCode));343}344// ---- DefaultController345export function setUpReadableStreamDefaultController<OutputType>(stream: SDReadableStream<OutputType>, controller: SDReadableStreamDefaultController<OutputType>, startAlgorithm: StartAlgorithm, pullAlgorithm: PullAlgorithm<OutputType>, cancelAlgorithm: CancelAlgorithm, highWaterMark: number, sizeAlgorithm: QueuingStrategySize<OutputType>) {346	// Assert: stream.[[readableStreamController]] is undefined.347	controller[controlledReadableStream_] = stream;348	q.resetQueue(controller);349	controller[started_] = false;350	controller[closeRequested_] = false;351	controller[pullAgain_] = false;352	controller[pulling_] = false;353	controller[strategySizeAlgorithm_] = sizeAlgorithm;354	controller[strategyHWM_] = highWaterMark;355	controller[pullAlgorithm_] = pullAlgorithm;356	controller[cancelAlgorithm_] = cancelAlgorithm;357	stream[readableStreamController_] = controller;358	const startResult = startAlgorithm();359	Promise.resolve(startResult).then(360		_ => {361			controller[started_] = true;362			// Assert: controller.[[pulling]] is false.363			// Assert: controller.[[pullAgain]] is false.364			readableStreamDefaultControllerCallPullIfNeeded(controller);365		},366		error => {367			readableStreamDefaultControllerError(controller, error);368		}369	);370}371export function isReadableStreamDefaultController(value: unknown): value is SDReadableStreamDefaultController<any> {372	if (typeof value !== "object" || value === null) {373		return false;374	}375	return controlledReadableStream_ in value;376}377export function readableStreamDefaultControllerHasBackpressure<OutputType>(controller: SDReadableStreamDefaultController<OutputType>) {378	return ! readableStreamDefaultControllerShouldCallPull(controller);379}380export function readableStreamDefaultControllerCanCloseOrEnqueue<OutputType>(controller: SDReadableStreamDefaultController<OutputType>) {381	const state = controller[controlledReadableStream_][shared.state_];382	return controller[closeRequested_] === false && state === "readable";383}384export function readableStreamDefaultControllerGetDesiredSize<OutputType>(controller: SDReadableStreamDefaultController<OutputType>) {385	const state = controller[controlledReadableStream_][shared.state_];386	if (state === "errored") {387		return null;388	}389	if (state === "closed") {390		return 0;391	}392	return controller[strategyHWM_] - controller[q.queueTotalSize_];393}394export function readableStreamDefaultControllerClose<OutputType>(controller: SDReadableStreamDefaultController<OutputType>) {395	// Assert: !ReadableStreamDefaultControllerCanCloseOrEnqueue(controller) is true.396	controller[closeRequested_] = true;397	const stream = controller[controlledReadableStream_];398	if (controller[q.queue_].length === 0) {399		readableStreamDefaultControllerClearAlgorithms(controller);400		readableStreamClose(stream);401	}402}403export function readableStreamDefaultControllerEnqueue<OutputType>(controller: SDReadableStreamDefaultController<OutputType>, chunk: OutputType) {404	const stream = controller[controlledReadableStream_];405	// Assert: !ReadableStreamDefaultControllerCanCloseOrEnqueue(controller) is true.406	if (isReadableStreamLocked(stream) && readableStreamGetNumReadRequests(stream) > 0) {407		readableStreamFulfillReadRequest(stream, chunk, false);408	}409	else {410		// Let result be the result of performing controller.[[strategySizeAlgorithm]], passing in chunk,411		// and interpreting the result as an ECMAScript completion value.412		// impl note: assuming that in JS land this just means try/catch with rethrow413		let chunkSize: number;414		try {415			chunkSize = controller[strategySizeAlgorithm_](chunk);416		}417		catch (error) {418			readableStreamDefaultControllerError(controller, error);419			throw error;420		}421		try {422			q.enqueueValueWithSize(controller, chunk, chunkSize);423		}424		catch (error) {425			readableStreamDefaultControllerError(controller, error);426			throw error;427		}428	}429	readableStreamDefaultControllerCallPullIfNeeded(controller);430}431export function readableStreamDefaultControllerError<OutputType>(controller: SDReadableStreamDefaultController<OutputType>, error: shared.ErrorResult) {432	const stream = controller[controlledReadableStream_];433	if (stream[shared.state_] !== "readable") {434		return;435	}436	q.resetQueue(controller);437	readableStreamDefaultControllerClearAlgorithms(controller);438	readableStreamError(stream, error);439}440export function readableStreamDefaultControllerCallPullIfNeeded<OutputType>(controller: SDReadableStreamDefaultController<OutputType>) {441	if (! readableStreamDefaultControllerShouldCallPull(controller)) {442		return;443	}444	if (controller[pulling_]) {445		controller[pullAgain_] = true;446		return;447	}448	if (controller[pullAgain_]) {449		throw new RangeError("Stream controller is in an invalid state.");450	}451	controller[pulling_] = true;452	controller[pullAlgorithm_](controller).then(453		_ => {454			controller[pulling_] = false;455			if (controller[pullAgain_]) {456				controller[pullAgain_] = false;457				readableStreamDefaultControllerCallPullIfNeeded(controller);458			}459		},460		error => {461			readableStreamDefaultControllerError(controller, error);462		}463	);464}465export function readableStreamDefaultControllerShouldCallPull<OutputType>(controller: SDReadableStreamDefaultController<OutputType>) {466	const stream = controller[controlledReadableStream_];467	if (! readableStreamDefaultControllerCanCloseOrEnqueue(controller)) {468		return false;469	}470	if (controller[started_] === false) {471		return false;472	}473	if (isReadableStreamLocked(stream) && readableStreamGetNumReadRequests(stream) > 0) {474		return true;475	}476	const desiredSize = readableStreamDefaultControllerGetDesiredSize(controller);477	if (desiredSize === null) {478		throw new RangeError("Stream is in an invalid state.");479	}480	return desiredSize > 0;481}482export function readableStreamDefaultControllerClearAlgorithms<OutputType>(controller: SDReadableStreamDefaultController<OutputType>) {483	controller[pullAlgorithm_] = undefined!;484	controller[cancelAlgorithm_] = undefined!;485	controller[strategySizeAlgorithm_] = undefined!;486}487// ---- BYOBController488export function setUpReadableByteStreamController(stream: SDReadableStream<ArrayBufferView>, controller: SDReadableByteStreamController, startAlgorithm: StartAlgorithm, pullAlgorithm: PullAlgorithm<ArrayBufferView>, cancelAlgorithm: CancelAlgorithm, highWaterMark: number, autoAllocateChunkSize: number | undefined) {489	// Assert: stream.[[readableStreamController]] is undefined.490	if (stream[readableStreamController_] !== undefined) {491		throw new TypeError("Cannot reuse streams");492	}493	if (autoAllocateChunkSize !== undefined) {494		if (! shared.isInteger(autoAllocateChunkSize) || autoAllocateChunkSize <= 0) {495			throw new RangeError("autoAllocateChunkSize must be a positive, finite integer");496		}497	}498	// Set controller.[[controlledReadableByteStream]] to stream.499	controller[controlledReadableByteStream_] = stream;500	// Set controller.[[pullAgain]] and controller.[[pulling]] to false.501	controller[pullAgain_] = false;502	controller[pulling_] = false;503	readableByteStreamControllerClearPendingPullIntos(controller);504	q.resetQueue(controller);505	controller[closeRequested_] = false;506	controller[started_] = false;507	controller[strategyHWM_] = shared.validateAndNormalizeHighWaterMark(highWaterMark);508	controller[pullAlgorithm_] = pullAlgorithm;509	controller[cancelAlgorithm_] = cancelAlgorithm;510	controller[autoAllocateChunkSize_] = autoAllocateChunkSize;511	controller[pendingPullIntos_] = [];512	stream[readableStreamController_] = controller;513	// Let startResult be the result of performing startAlgorithm.514	const startResult = startAlgorithm();515	Promise.resolve(startResult).then(516		_ => {517			controller[started_] = true;518			// Assert: controller.[[pulling]] is false.519			// Assert: controller.[[pullAgain]] is false.520			readableByteStreamControllerCallPullIfNeeded(controller);521		},522		error => {523			readableByteStreamControllerError(controller, error);524		}525	);526}527export function isReadableStreamBYOBRequest(value: unknown): value is SDReadableStreamBYOBRequest {528	if (typeof value !== "object" || value === null) {529		return false;530	}531	return associatedReadableByteStreamController_ in value;532}533export function isReadableByteStreamController(value: unknown): value is SDReadableByteStreamController {534	if (typeof value !== "object" || value === null) {535		return false;536	}537	return controlledReadableByteStream_ in value;538}539export function readableByteStreamControllerCallPullIfNeeded(controller: SDReadableByteStreamController) {540	if (! readableByteStreamControllerShouldCallPull(controller)) {541		return;542	}543	if (controller[pulling_]) {544		controller[pullAgain_] = true;545		return;546	}547	// Assert: controller.[[pullAgain]] is false.548	controller[pulling_] = true;549	controller[pullAlgorithm_](controller).then(550		_ => {551			controller[pulling_] = false;552			if (controller[pullAgain_]) {553				controller[pullAgain_] = false;554				readableByteStreamControllerCallPullIfNeeded(controller);555			}556		},557		error => {558			readableByteStreamControllerError(controller, error);559		}560	);561}562export function readableByteStreamControllerClearAlgorithms(controller: SDReadableByteStreamController) {563	controller[pullAlgorithm_] = undefined!;564	controller[cancelAlgorithm_] = undefined!;565}566export function readableByteStreamControllerClearPendingPullIntos(controller: SDReadableByteStreamController) {567	readableByteStreamControllerInvalidateBYOBRequest(controller);568	controller[pendingPullIntos_] = [];569}570export function readableByteStreamControllerClose(controller: SDReadableByteStreamController) {571	const stream = controller[controlledReadableByteStream_];572	// Assert: controller.[[closeRequested]] is false.573	// Assert: stream.[[state]] is "readable".574	if (controller[q.queueTotalSize_] > 0) {575		controller[closeRequested_] = true;576		return;577	}578	if (controller[pendingPullIntos_].length > 0) {579		const firstPendingPullInto = controller[pendingPullIntos_][0];580		if (firstPendingPullInto.bytesFilled > 0) {581			const error = new TypeError();582			readableByteStreamControllerError(controller, error);583			throw error;584		}585	}586	readableByteStreamControllerClearAlgorithms(controller);587	readableStreamClose(stream);588}589export function readableByteStreamControllerCommitPullIntoDescriptor(stream: SDReadableStream<ArrayBufferView>, pullIntoDescriptor: PullIntoDescriptor) {590	// Assert: stream.[[state]] is not "errored".591	let done = false;592	if (stream[shared.state_] === "closed") {593		// Assert: pullIntoDescriptor.[[bytesFilled]] is 0.594		done = true;595	}596	const filledView = readableByteStreamControllerConvertPullIntoDescriptor(pullIntoDescriptor);597	if (pullIntoDescriptor.readerType === "default") {598		readableStreamFulfillReadRequest(stream, filledView, done);599	}600	else {601		// Assert: pullIntoDescriptor.[[readerType]] is "byob".602		readableStreamFulfillReadIntoRequest(stream, filledView, done);603	}604}605export function readableByteStreamControllerConvertPullIntoDescriptor(pullIntoDescriptor: PullIntoDescriptor) {606	const { bytesFilled, elementSize } = pullIntoDescriptor;607	// Assert: bytesFilled <= pullIntoDescriptor.byteLength608	// Assert: bytesFilled mod elementSize is 0609	const buffer = shared.transferArrayBuffer(pullIntoDescriptor.buffer);610	return new pullIntoDescriptor.ctor(buffer, pullIntoDescriptor.byteOffset, bytesFilled / elementSize);611}612export function readableByteStreamControllerEnqueue(controller: SDReadableByteStreamController, chunk: ArrayBufferView) {613	const stream = controller[controlledReadableByteStream_];614	// Assert: controller.[[closeRequested]] is false.615	// Assert: stream.[[state]] is "readable".616	const { buffer, byteOffset, byteLength } = chunk;617	618	// If buffer is detached, throw a TypeError619	const transferredBuffer = shared.transferArrayBuffer(buffer);620	if (controller[pendingPullIntos_].length > 0) {621		const firstPendingPullInto = controller[pendingPullIntos_][0];622		// If firstPendingPullInto.buffer is detached throw a TypeError623		firstPendingPullInto.buffer = shared.transferArrayBuffer(firstPendingPullInto.buffer);624	}625	readableByteStreamControllerInvalidateBYOBRequest(controller);626	if (readableStreamHasDefaultReader(stream)) {627		if (readableStreamGetNumReadRequests(stream) === 0) {628			readableByteStreamControllerEnqueueChunkToQueue(controller, transferredBuffer, byteOffset, byteLength);629		}630		else {631			// Assert: controller.[[queue]] is empty.632			const transferredView = new Uint8Array(transferredBuffer, byteOffset, byteLength);633			readableStreamFulfillReadRequest(stream, transferredView, false);634		}635	}636	else if (readableStreamHasBYOBReader(stream)) {637		readableByteStreamControllerEnqueueChunkToQueue(controller, transferredBuffer, byteOffset, byteLength);638		readableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller);639	}640	else {641		// Assert: !IsReadableStreamLocked(stream) is false.642		readableByteStreamControllerEnqueueChunkToQueue(controller, transferredBuffer, byteOffset, byteLength);643	}644	readableByteStreamControllerCallPullIfNeeded(controller);645}646export function readableByteStreamControllerEnqueueChunkToQueue(controller: SDReadableByteStreamController, buffer: ArrayBufferLike, byteOffset: number, byteLength: number) {647	controller[q.queue_].push({ buffer, byteOffset, byteLength });648	controller[q.queueTotalSize_] += byteLength;649}650export function readableByteStreamControllerError(controller: SDReadableByteStreamController, error: shared.ErrorResult) {651	const stream = controller[controlledReadableByteStream_];652	if (stream[shared.state_] !== "readable") {653		return;654	}655	readableByteStreamControllerClearPendingPullIntos(controller);656	q.resetQueue(controller);657	readableByteStreamControllerClearAlgorithms(controller);658	readableStreamError(stream, error);659}660export function readableByteStreamControllerFillHeadPullIntoDescriptor(_controller: SDReadableByteStreamController, size: number, pullIntoDescriptor: PullIntoDescriptor) {661	// Assert: either controller.[[pendingPullIntos]] is empty, or the first element of controller.[[pendingPullIntos]] is pullIntoDescriptor.662	// Assert: controller.[[byobRequest]] is null663	pullIntoDescriptor.bytesFilled += size;664}665export function readableByteStreamControllerFillPullIntoDescriptorFromQueue(controller: SDReadableByteStreamController, pullIntoDescriptor: PullIntoDescriptor) {666	const elementSize = pullIntoDescriptor.elementSize;667	const currentAlignedBytes = pullIntoDescriptor.bytesFilled - (pullIntoDescriptor.bytesFilled % elementSize);668	const maxBytesToCopy = Math.min(controller[q.queueTotalSize_], pullIntoDescriptor.byteLength - pullIntoDescriptor.bytesFilled);669	const maxBytesFilled = pullIntoDescriptor.bytesFilled + maxBytesToCopy;670	const maxAlignedBytes = maxBytesFilled - (maxBytesFilled % elementSize);671	let totalBytesToCopyRemaining = maxBytesToCopy;672	let ready = false;673	if (maxAlignedBytes > currentAlignedBytes) {674		totalBytesToCopyRemaining = maxAlignedBytes - pullIntoDescriptor.bytesFilled;675		ready = true;676	}677	const queue = controller[q.queue_];678	while (totalBytesToCopyRemaining > 0) {679		const headOfQueue = queue.front()!;680		const bytesToCopy = Math.min(totalBytesToCopyRemaining, headOfQueue.byteLength);681		const destStart = pullIntoDescriptor.byteOffset + pullIntoDescriptor.bytesFilled;682		shared.copyDataBlockBytes(pullIntoDescriptor.buffer, destStart, headOfQueue.buffer, headOfQueue.byteOffset, bytesToCopy);683		if (headOfQueue.byteLength === bytesToCopy) {684			queue.shift();685		}686		else {687			headOfQueue.byteOffset += bytesToCopy;688			headOfQueue.byteLength -= bytesToCopy;689		}690		controller[q.queueTotalSize_] -= bytesToCopy;691		readableByteStreamControllerFillHeadPullIntoDescriptor(controller, bytesToCopy, pullIntoDescriptor);692		totalBytesToCopyRemaining -= bytesToCopy;693	}694	if (! ready) {695		// Assert: controller[queueTotalSize_] === 0696		// Assert: pullIntoDescriptor.bytesFilled > 0697		// Assert: pullIntoDescriptor.bytesFilled < pullIntoDescriptor.elementSize698	}699	return ready;700}701export function readableByteStreamControllerGetDesiredSize(controller: SDReadableByteStreamController) {702	const stream = controller[controlledReadableByteStream_];703	const state = stream[shared.state_];704	if (state === "errored") {705		return null;706	}707	if (state === "closed") {708		return 0;709	}710	return controller[strategyHWM_] - controller[q.queueTotalSize_];711}712export function readableByteStreamControllerHandleQueueDrain(controller: SDReadableByteStreamController) {713	// Assert: controller.[[controlledReadableByteStream]].[[state]] is "readable".714	if (controller[q.queueTotalSize_] === 0 && controller[closeRequested_]) {715		readableByteStreamControllerClearAlgorithms(controller);716		readableStreamClose(controller[controlledReadableByteStream_]);717	}718	else {719		readableByteStreamControllerCallPullIfNeeded(controller);720	}721}722export function readableByteStreamControllerInvalidateBYOBRequest(controller: SDReadableByteStreamController) {723	const byobRequest = controller[byobRequest_];724	if (byobRequest === undefined) {725		return;726	}727	byobRequest[associatedReadableByteStreamController_] = undefined;728	byobRequest[view_] = undefined;729	controller[byobRequest_] = undefined;730}731export function readableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller: SDReadableByteStreamController) {732	// Assert: controller.[[closeRequested]] is false.733	const pendingPullIntos = controller[pendingPullIntos_];734	while (pendingPullIntos.length > 0) {735		if (controller[q.queueTotalSize_] === 0) {736			return;737		}738		const pullIntoDescriptor = pendingPullIntos[0];739		if (readableByteStreamControllerFillPullIntoDescriptorFromQueue(controller, pullIntoDescriptor)) {740			readableByteStreamControllerShiftPendingPullInto(controller);741			readableByteStreamControllerCommitPullIntoDescriptor(controller[controlledReadableByteStream_], pullIntoDescriptor);742		}743	}744}745export function readableByteStreamControllerPullInto(controller: SDReadableByteStreamController, view: ArrayBufferView, forAuthorCode: boolean) {746	const stream = controller[controlledReadableByteStream_];747	const elementSize = (view as Uint8Array).BYTES_PER_ELEMENT || 1; // DataView exposes this in Webkit as 1, is not present in FF or Blink748	const ctor = view.constructor as Uint8ArrayConstructor; // the typecast here is just for TS typing, it does not influence buffer creation749	const byteOffset = view.byteOffset;750	const byteLength = view.byteLength;751	// In Ref Impl: this can fail (detached) and needs to result in byobReader.read failure752	let buffer = shared.transferArrayBuffer(view.buffer);753	const pullIntoDescriptor: PullIntoDescriptor = { buffer, bufferByteLength: buffer.byteLength, byteOffset, byteLength, bytesFilled: 0, elementSize, ctor, readerType: "byob" };754	if (controller[pendingPullIntos_].length > 0) {755		controller[pendingPullIntos_].push(pullIntoDescriptor);756		return readableStreamAddReadIntoRequest(stream, forAuthorCode);757	}758	if (stream[shared.state_] === "closed") {759		const emptyView = new ctor(pullIntoDescriptor.buffer, pullIntoDescriptor.byteOffset, 0);760		return Promise.resolve(readableStreamCreateReadResult(emptyView, true, forAuthorCode));761	}762	if (controller[q.queueTotalSize_] > 0) {763		if (readableByteStreamControllerFillPullIntoDescriptorFromQueue(controller, pullIntoDescriptor)) {764			const filledView = readableByteStreamControllerConvertPullIntoDescriptor(pullIntoDescriptor);765			readableByteStreamControllerHandleQueueDrain(controller);766			return Promise.resolve(readableStreamCreateReadResult(filledView, false, forAuthorCode));767		}768		if (controller[closeRequested_]) {769			const error = new TypeError();770			readableByteStreamControllerError(controller, error);771			return Promise.reject(error);772		}773	}774	controller[pendingPullIntos_].push(pullIntoDescriptor);775	const promise = readableStreamAddReadIntoRequest(stream, forAuthorCode);776	readableByteStreamControllerCallPullIfNeeded(controller);777	return promise;778}779export function readableByteStreamControllerRespond(controller: SDReadableByteStreamController, bytesWritten: number) {780	bytesWritten = Number(bytesWritten);781	if (! shared.isFiniteNonNegativeNumber(bytesWritten)) {782		throw new RangeError("bytesWritten must be a finite, non-negative number");783	}784	// Assert: controller.[[pendingPullIntos]] is not empty.785	const firstDescriptor = controller[pendingPullIntos_][0];786	const state = controller[controlledReadableByteStream_][shared.state_];787	if (state === "closed") {788		if (bytesWritten !== 0) {789			throw new TypeError('bytesWritten must be 0 when calling respond() on a closed stream');790		}791	}792	else {793		// Assert: state === "readable"794		if (firstDescriptor.bytesFilled + bytesWritten > firstDescriptor.byteLength) {795			throw new RangeError("bytesWritten out of range");796		}	 797	}798	firstDescriptor.buffer = shared.transferArrayBuffer(firstDescriptor.buffer);799	readableByteStreamControllerRespondInternal(controller, bytesWritten);800}801export function readableByteStreamControllerRespondInClosedState(controller: SDReadableByteStreamController, _firstDescriptor: PullIntoDescriptor) {802	// Assert: firstDescriptor.[[bytesFilled]] is 0.803	const stream = controller[controlledReadableByteStream_];804	if (readableStreamHasBYOBReader(stream)) {805		while (readableStreamGetNumReadIntoRequests(stream) > 0) {806			const pullIntoDescriptor = readableByteStreamControllerShiftPendingPullInto(controller)!;807			readableByteStreamControllerCommitPullIntoDescriptor(stream, pullIntoDescriptor);808		}809	}810}811export function readableByteStreamControllerRespondInReadableState(controller: SDReadableByteStreamController, bytesWritten: number, pullIntoDescriptor: PullIntoDescriptor) {812	// Assert: pullIntoDescriptor.[[bytesFilled]] + bytesWritten <= pullIntoDescriptor.[[byteLength]]813	readableByteStreamControllerFillHeadPullIntoDescriptor(controller, bytesWritten, pullIntoDescriptor);814	if (pullIntoDescriptor.bytesFilled < pullIntoDescriptor.elementSize) {815		return;816	}817	readableByteStreamControllerShiftPendingPullInto(controller);818	const remainderSize = pullIntoDescriptor.bytesFilled % pullIntoDescriptor.elementSize;819	if (remainderSize > 0) {820		const end = pullIntoDescriptor.byteOffset + pullIntoDescriptor.bytesFilled;821		const remainder = shared.cloneArrayBuffer(pullIntoDescriptor.buffer, end - remainderSize, remainderSize, ArrayBuffer);822		readableByteStreamControllerEnqueueChunkToQueue(controller, remainder, 0, remainder.byteLength);823	}824	pullIntoDescriptor.bytesFilled -= remainderSize;825	readableByteStreamControllerCommitPullIntoDescriptor(controller[controlledReadableByteStream_], pullIntoDescriptor);826	readableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller);827}828export function readableByteStreamControllerRespondInternal(controller: SDReadableByteStreamController, bytesWritten: number) {829	const firstDescriptor = controller[pendingPullIntos_][0];830	// Assert: canTransferArrayBuffer(firstDescriptor.buffer)831	readableByteStreamControllerInvalidateBYOBRequest(controller);832	const stream = controller[controlledReadableByteStream_];833	if (stream[shared.state_] === "closed") {834		// Assert: bytesWritten === 0835		readableByteStreamControllerRespondInClosedState(controller, firstDescriptor);836	}837	else {838		// Assert: stream.[[state]] is "readable".839		// Assert: bytesWritten > 0840		readableByteStreamControllerRespondInReadableState(controller, bytesWritten, firstDescriptor);841	}842	readableByteStreamControllerCallPullIfNeeded(controller);843}844export function readableByteStreamControllerRespondWithNewView(controller: SDReadableByteStreamController, view: ArrayBufferView) {845	// Assert: controller.[[pendingPullIntos]] is not empty.846	// Assert: view.buffer is not detached847	const firstDescriptor = controller[pendingPullIntos_][0];848	const state = controller[controlledReadableByteStream_][shared.state_];849	if (state === "closed") {850		if (view.byteLength !== 0) {851			throw new TypeError("The view's length must be 0 when calling respondWithNewView() on a closed stream");852		}853	}854	else {855		// Assert: state === "readable"856		if (view.byteLength === 0) {857			throw new RangeError("The view's length must be greater than 0 when calling respondWithNewView() on a readable stream");858		}	 859	}860	if (firstDescriptor.byteOffset + firstDescriptor.bytesFilled !== view.byteOffset) {861		throw new RangeError("The region specified by view does not match byobRequest");862	} 863	if (firstDescriptor.bufferByteLength !== view.buffer.byteLength) {864		throw new RangeError("The buffer of view has different capacity than byobRequest");865	}866	firstDescriptor.buffer = shared.transferArrayBuffer(view.buffer);867	readableByteStreamControllerRespondInternal(controller, view.byteLength);868}869export function readableByteStreamControllerShiftPendingPullInto(controller: SDReadableByteStreamController) {870	// Assert: controller.[[byobRequest]] is null871	const descriptor = controller[pendingPullIntos_].shift();872	return descriptor;873}874export function readableByteStreamControllerShouldCallPull(controller: SDReadableByteStreamController) {875	// Let stream be controller.[[controlledReadableByteStream]].876	const stream = controller[controlledReadableByteStream_];877	if (stream[shared.state_] !== "readable") {878		return false;879	}880	if (controller[closeRequested_]) {881		return false;882	}883	if (! controller[started_]) {884		return false;885	}886	if (readableStreamHasDefaultReader(stream) && readableStreamGetNumReadRequests(stream) > 0) {887		return true;888	}889	if (readableStreamHasBYOBReader(stream) && readableStreamGetNumReadIntoRequests(stream) > 0) {890		return true;891	}892	const desiredSize = readableByteStreamControllerGetDesiredSize(controller);893	// Assert: desiredSize is not null.894	return desiredSize! > 0;895}896export function setUpReadableStreamBYOBRequest(request: SDReadableStreamBYOBRequest, controller: SDReadableByteStreamController, view: ArrayBufferView) {897	if (! isReadableByteStreamController(controller)) {898		throw new TypeError();899	}900	if (! ArrayBuffer.isView(view)) {901		throw new TypeError();902	}903	// Assert: !IsDetachedBuffer(view.[[ViewedArrayBuffer]]) is false.904	request[associatedReadableByteStreamController_] = controller;905	request[view_] = view;...

byte-stream-controller.ts

Source:byte-stream-controller.ts

...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);...

readable_byte_stream_controller.ts

Source:readable_byte_stream_controller.ts

...287      transferredBuffer,288      byteOffset,289      byteLength290    );291    ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(292      controller293    );294  } else {295    Assert(296      IsReadableStreamLocked(stream) === false,297      "stream should not be locked"298    );299    ReadableByteStreamControllerEnqueueChunkToQueue(300      controller,301      transferredBuffer,302      byteOffset,303      byteLength304    );305  }306  ReadableByteStreamControllerCallPullIfNeeded(controller);307}308export function ReadableByteStreamControllerEnqueueChunkToQueue(309  controller: ReadableByteStreamController,310  buffer: ArrayBuffer,311  byteOffset: number,312  byteLength: number313) {314  controller.queue.push({315    buffer,316    byteOffset,317    byteLength318  });319  controller.queueTotalSize += byteLength;320}321export function ReadableByteStreamControllerError(322  controller: ReadableByteStreamController,323  e324) {325  const stream = controller.controlledReadableByteStream;326  if (stream.state !== "readable") {327    return;328  }329  ReadableByteStreamControllerClearPendingPullIntos(controller);330  ResetQueue(controller);331  ReadableByteStreamControllerClearAlgorithms(controller);332  ReadableStreamError(controller.controlledReadableByteStream, e);333}334export function ReadableByteStreamControllerFillHeadPullIntoDescriptor(335  controller: ReadableByteStreamController,336  size: number,337  pullIntoDescriptor: PullIntoDescriptor338) {339  Assert(340    controller.pendingPullIntos.length === 0 ||341      controller.pendingPullIntos[0] === pullIntoDescriptor342  );343  ReadableByteStreamControllerInvalidateBYOBRequest(controller);344  pullIntoDescriptor.bytesFilled += size;345}346export function ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(347  controller: ReadableByteStreamController,348  pullIntoDescriptor: PullIntoDescriptor349): boolean {350  const { elementSize } = pullIntoDescriptor;351  const currentAlignedBytes =352    pullIntoDescriptor.bytesFilled -353    (pullIntoDescriptor.bytesFilled % elementSize);354  const maxBytesToCopy = Math.min(355    controller.queueTotalSize,356    pullIntoDescriptor.byteLength - pullIntoDescriptor.bytesFilled357  );358  const maxBytesFilled = pullIntoDescriptor.bytesFilled + maxBytesToCopy;359  const maxAlignedBytes = maxBytesFilled - (maxBytesFilled % elementSize);360  let totalBytesToCopyRemaining = maxBytesToCopy;361  let ready = false;362  if (maxAlignedBytes > currentAlignedBytes) {363    totalBytesToCopyRemaining =364      maxAlignedBytes - pullIntoDescriptor.bytesFilled;365    ready = true;366  }367  const { queue } = controller;368  while (totalBytesToCopyRemaining > 0) {369    const headOfQueue = queue[0];370    const bytesToCopy = Math.min(371      totalBytesToCopyRemaining,372      headOfQueue.byteLength373    );374    const destStart =375      pullIntoDescriptor.byteOffset + pullIntoDescriptor.bytesFilled;376    const srcView = new Uint8Array(377      headOfQueue.buffer,378      headOfQueue.byteOffset,379      headOfQueue.byteLength380    );381    const destView = new Uint8Array(382      pullIntoDescriptor.buffer,383      destStart,384      bytesToCopy385    );386    for (let i = 0; i < bytesToCopy; i++) {387      destView[i] = srcView[i];388    }389    if (headOfQueue.byteLength === bytesToCopy) {390      queue.shift();391    } else {392      headOfQueue.byteOffset += bytesToCopy;393      headOfQueue.byteLength -= bytesToCopy;394    }395    controller.queueTotalSize -= bytesToCopy;396    ReadableByteStreamControllerFillHeadPullIntoDescriptor(397      controller,398      bytesToCopy,399      pullIntoDescriptor400    );401    totalBytesToCopyRemaining -= bytesToCopy;402  }403  if (ready === false) {404    Assert(controller.queueTotalSize === 0);405    Assert(pullIntoDescriptor.bytesFilled > 0);406    Assert(pullIntoDescriptor.bytesFilled < pullIntoDescriptor.elementSize);407  }408  return ready;409}410export function ReadableByteStreamControllerGetDesiredSize(411  controller: ReadableByteStreamController412): number | null {413  const stream = controller.controlledReadableByteStream;414  const { state } = stream;415  if (state === "errored") {416    return null;417  }418  if (state === "closed") {419    return 0;420  }421  return controller.strategyHWM - controller.queueTotalSize;422}423export function ReadableByteStreamControllerHandleQueueDrain(424  controller: ReadableByteStreamController425) {426  Assert(controller.controlledReadableByteStream.state === "readable");427  if (controller.queueTotalSize === 0 && controller.closeRequested) {428    ReadableByteStreamControllerClearAlgorithms(controller);429    ReadableStreamClose(controller.controlledReadableByteStream);430  } else {431    ReadableByteStreamControllerCallPullIfNeeded(controller);432  }433}434export function ReadableByteStreamControllerInvalidateBYOBRequest(435  controller: ReadableByteStreamController436) {437  if (controller._byobRequest === void 0) {438    return;439  }440  controller._byobRequest.associatedReadableByteStreamController = void 0;441  controller._byobRequest._view = void 0;442  controller._byobRequest = void 0;443}444export function ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(445  controller: ReadableByteStreamController446) {447  Assert(controller.closeRequested === false);448  while (controller.pendingPullIntos.length > 0) {449    if (controller.queueTotalSize === 0) {450      return;451    }452    const pullIntoDescriptor = controller.pendingPullIntos[0];453    if (454      ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(455        controller,456        pullIntoDescriptor457      ) === true458    ) {459      ReadableByteStreamControllerShiftPendingPullInto(controller);460      ReadableByteStreamControllerCommitPullIntoDescriptor(461        controller.controlledReadableByteStream,462        pullIntoDescriptor463      );464    }465  }466}467const TypedArraySizeMap = {468  Int8Array: [1, Int8Array],469  Uint8Array: [1, Uint8Array],470  Uint8ClampedArray: [1, Uint8ClampedArray],471  Int16Array: [2, Int16Array],472  Uint16Array: [2, Uint16Array],473  Int32Array: [4, Int32Array],474  Uint32Array: [4, Uint32Array],475  Float32Array: [4, Float32Array],476  Float64Array: [8, Float64Array]477};478export function ReadableByteStreamControllerPullInto(479  controller: ReadableByteStreamController,480  view: ArrayBufferView,481  forAuthorCode?: boolean482): Promise<any> {483  const stream = controller.controlledReadableByteStream;484  let elementSize = 1;485  let ctor = DataView;486  const ctorName = view.constructor.name;487  if (TypedArraySizeMap[ctorName]) {488    [elementSize, ctor] = TypedArraySizeMap[ctorName];489  }490  const { byteOffset, byteLength } = view;491  const buffer = TransferArrayBuffer(view.buffer);492  const pullIntoDescriptor: PullIntoDescriptor = {493    buffer,494    byteOffset,495    byteLength,496    bytesFilled: 0,497    elementSize,498    ctor,499    readerType: "byob"500  };501  if (controller.pendingPullIntos.length > 0) {502    controller.pendingPullIntos.push(pullIntoDescriptor);503    return ReadableStreamAddReadIntoRequest(stream, forAuthorCode);504  }505  if (stream.state === "closed") {506    const emptyView = new ctor(507      pullIntoDescriptor.buffer,508      pullIntoDescriptor.byteOffset,509      0510    );511    return Promise.resolve(512      ReadableStreamCreateReadResult(emptyView, true, forAuthorCode)513    );514  }515  if (controller.queueTotalSize > 0) {516    if (517      ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(518        controller,519        pullIntoDescriptor520      )521    ) {522      const filedView = ReadableByteStreamControllerConvertPullIntoDescriptor(523        pullIntoDescriptor524      );525      ReadableByteStreamControllerHandleQueueDrain(controller);526      return Promise.resolve(527        ReadableStreamCreateReadResult(filedView, false, forAuthorCode)528      );529    }530    if (controller.closeRequested) {531      const e = new TypeError();532      ReadableByteStreamControllerError(controller, e);533      return Promise.reject(e);534    }535  }536  controller.pendingPullIntos.push(pullIntoDescriptor);537  const promise = ReadableStreamAddReadIntoRequest(stream, forAuthorCode);538  ReadableByteStreamControllerCallPullIfNeeded(controller);539  return promise;540}541export function ReadableByteStreamControllerRespond(542  controller: ReadableByteStreamController,543  bytesWritten: number544): void {545  if (IsFiniteNonNegativeNumber(bytesWritten) === false) {546    throw new RangeError();547  }548  Assert(controller.pendingPullIntos.length > 0);549  ReadableByteStreamControllerRespondInternal(controller, bytesWritten);550}551export function ReadableByteStreamControllerRespondInClosedState(552  controller: ReadableByteStreamController,553  firstDescriptor: PullIntoDescriptor554) {555  firstDescriptor.buffer = TransferArrayBuffer(firstDescriptor.buffer);556  Assert(firstDescriptor.bytesFilled === 0);557  const stream = controller.controlledReadableByteStream;558  if (ReadableStreamHasBYOBReader(stream)) {559    while (ReadableStreamGetNumReadIntoRequests(stream) > 0) {560      const pullIntoDescriptor = ReadableByteStreamControllerShiftPendingPullInto(561        controller562      );563      ReadableByteStreamControllerCommitPullIntoDescriptor(564        stream,565        pullIntoDescriptor566      );567    }568  }569}570export function ReadableByteStreamControllerRespondInReadableState(571  controller: ReadableByteStreamController,572  bytesWritten: number,573  pullIntoDescriptor: PullIntoDescriptor574) {575  if (576    pullIntoDescriptor.bytesFilled + bytesWritten >577    pullIntoDescriptor.byteLength578  ) {579    throw new RangeError();580  }581  ReadableByteStreamControllerFillHeadPullIntoDescriptor(582    controller,583    bytesWritten,584    pullIntoDescriptor585  );586  if (pullIntoDescriptor.bytesFilled < pullIntoDescriptor.elementSize) {587    return;588  }589  ReadableByteStreamControllerShiftPendingPullInto(controller);590  const remainderSize =591    pullIntoDescriptor.bytesFilled % pullIntoDescriptor.elementSize;592  if (remainderSize > 0) {593    const end = pullIntoDescriptor.byteOffset + pullIntoDescriptor.bytesFilled;594    const remainder = CloneArrayBuffer(595      pullIntoDescriptor.buffer,596      end - remainderSize,597      remainderSize598    );599    ReadableByteStreamControllerEnqueueChunkToQueue(600      controller,601      remainder,602      0,603      remainder.byteLength604    );605  }606  pullIntoDescriptor.buffer = TransferArrayBuffer(pullIntoDescriptor.buffer);607  pullIntoDescriptor.bytesFilled =608    pullIntoDescriptor.bytesFilled - remainderSize;609  ReadableByteStreamControllerCommitPullIntoDescriptor(610    controller.controlledReadableByteStream,611    pullIntoDescriptor612  );613  ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller);614}615function CloneArrayBuffer(616  srcBuffer: ArrayBuffer,617  srcByteOffset: number,618  srcLength: number619): ArrayBuffer {620  const ret = new ArrayBuffer(srcLength);621  const retView = new DataView(ret);622  const srcView = new DataView(srcBuffer, srcByteOffset, srcLength);623  for (let i = 0; i < srcLength; i++) {624    retView[i] = srcView[i];625  }626  return ret;627}...

Using AI Code Generation

1var rs = new ReadableStream({2  pull: function(controller) {3    var view = new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);4    var byobRequest = controller.byobRequest;5    byobRequest.respondWithNewView(view);6    controller.close();7  }8});9var reader = rs.getReader({ mode: 'byob' });10var result = reader.read(new Uint8Array(10));11result.then(function(r) {12  var view = r.value;13  var buffer = view.buffer;14  var byteOffset = view.byteOffset;15  var byteLength = view.byteLength;16  console.log('view.buffer=' + buffer);17  console.log('view.byteOffset=' + byteOffset);18  console.log('view.byteLength=' + byteLength);19  console.log('view=' + view);20});21result.catch(function(e) {22  console.log('read() failed: ' + e);23});

Using AI Code Generation

1var rs = new ReadableStream({2  start: function(controller) {3    controller.enqueue(new Uint8Array([1, 2, 3]));4  }5});6var reader = rs.getReader();7var readPromise = reader.read();8var pullPromise = readPromise.then(function(result) {9  assert_array_equals(result.value, [1, 2, 3], 'read() should fulfill with the enqueued chunk');10  return reader.read();11});12pullPromise.then(function(result) {13  assert_true(result.done, 'read() should fulfill with done:true');14  assert_array_equals(result.value, [], 'read() should fulfill with an empty array');15}, function(e) {16  assert_unreached('read() should not reject: ' + e);17}).then($DONE, $DONE);18var rs = new ReadableStream({19  start: function(controller) {20    controller.enqueue(new Uint8Array([1, 2, 3]));21  }22});23var reader = rs.getReader();24var readPromise = reader.read(new Uint8Array(4));25var pullPromise = readPromise.then(function(result) {26  assert_array_equals(result.value, [1, 2, 3], 'read() should fulfill with the enqueued chunk');27  return reader.read(new Uint8Array(4));28});29pullPromise.then(function(result) {30  assert_true(result.done, 'read() should fulfill with done:true');31  assert_array_equals(result.value, [], 'read() should fulfill with an empty array');32}, function(e) {33  assert_unreached('read() should not reject: ' + e);34}).then($DONE, $DONE);35var rs = new ReadableStream({36  start: function(controller) {37    controller.enqueue(new Uint8Array([1, 2, 3]));38  }39});40var reader = rs.getReader();41var readIntoPromise = reader.read(new Uint8Array(4));42var pullPromise = readIntoPromise.then(function(result) {43  assert_array_equals(result.value, [1, 2, 3

Using AI Code Generation

1var rs = new ReadableStream({2  pull: function(controller) {3    controller.enqueue(new Uint8Array([0x01, 0x02, 0x03]));4    controller.close();5  }6});7var reader = rs.getReader();8var result = reader.read();9result.then(function(result) {10  assert_array_equals(result.value, [0x01, 0x02, 0x03], 'value');11  assert_true(result.done, 'done');12});13var rs = new ReadableStream({14  pull: function(controller) {15    controller.enqueue(new Uint8Array([0x01, 0x02, 0x03]));16    controller.close();17  }18});19var reader = rs.getReader();20var result = reader.read();21result.then(function(result) {22  assert_array_equals(result.value, [0x01, 0x02, 0x03], 'value');23  assert_true(result.done, 'done');24});25var rs = new ReadableStream({26  pull: function(controller) {27    controller.enqueue(new Uint8Array([0x01, 0x02, 0x03]));28    controller.close();29  }30});31var reader = rs.getReader();32var result = reader.read();33result.then(function(result) {34  assert_array_equals(result.value, [0x01, 0x02, 0x03], 'value');35  assert_true(result.done, 'done');36});37var rs = new ReadableStream({38  pull: function(controller) {39    controller.enqueue(new Uint8Array([0x01, 0x02, 0x03]));40    controller.close();41  }42});43var reader = rs.getReader();44var result = reader.read();45result.then(function(result) {46  assert_array_equals(result.value, [

Using AI Code Generation

1var rs = new ReadableStream({2    pull: function (controller) {3        var view = new Uint8Array(16);4        controller.enqueue(view);5        controller.close();6    }7});8var reader = rs.getReader();9var readPromise = reader.read();10readPromise.then(function (result) {11    var view = result.value;12    assert_equals(view.length, 16, 'view length');13    assert_true(view instanceof Uint8Array, 'view type');14    assert_false(result.done, 'done');15});16var readPromise2 = reader.read();17readPromise2.then(function (result) {18    assert_true(result.done, 'done');19});20readPromise2.catch(function (e) {21    assert_unreached(e);22});23readPromise.catch(function (e) {24    assert_unreached(e);25});26var rs = new ReadableStream({27    pull: function (controller) {28        var view = new Uint8Array(16);29        controller.enqueue(view);30        controller.close();31    }32});33var reader = rs.getReader();34var readPromise = reader.read();35readPromise.then(function (result) {36    var view = result.value;37    assert_equals(view.length, 16, 'view length');38    assert_true(view instanceof Uint8Array, 'view type');39    assert_false(result.done, 'done');40});41var readPromise2 = reader.read();42readPromise2.then(function (result) {43    assert_true(result.done, 'done');44});45readPromise2.catch(function (e) {46    assert_unreached(e);47});48readPromise.catch(function (e) {49    assert_unreached(e);50});51var rs = new ReadableStream({52    pull: function (controller) {53        var view = new Uint8Array(16);54        controller.enqueue(view);55        controller.error();56    }57});58var reader = rs.getReader();59var readPromise = reader.read();60readPromise.then(function (result) {61    var view = result.value;62    assert_equals(view.length, 16, 'view length');63    assert_true(view instanceof Uint8

Using AI Code Generation

1var t = async_test("ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue method should throw a TypeError if this is not a ReadableByteStreamController instance.");2var rs = new ReadableStream({3    start: function(c) {4        t.step(function() {5            assert_throws(new TypeError(), function() {6                ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue.call(c, {});7            });8        });9        t.done();10    }11});12rs.getReader().read(new Uint8Array());

Using AI Code Generation

1var rs = new ReadableStream({2  pullIntoDescriptor: function() {3    return new ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(this);4  }5});6rs.pullIntoDescriptor();7var rs = new ReadableStream({8  respond: function() {9    return new ReadableByteStreamControllerRespond(this, 1);10  }11});12rs.respond();

Using AI Code Generation

1var rbs = new ReadableByteStream();2var controller = rbs.getController();3var pullIntoDescriptor = {bytesFilled: 0, elementSize: 1, byteLength: 2, byteOffset: 0, buffer: new ArrayBuffer(2), ctor: Uint8Array, type: "bytes"};4controller.enqueue(new Uint8Array([1,2,3,4]));5controller.enqueue(new Uint8Array([5,6,7,8]));6controller.close();7var result = controller.processPullIntoDescriptorsUsingQueue(pullIntoDescriptor);8assert_equals(result, 2);9assert_equals(pullIntoDescriptor.bytesFilled, 2);10assert_equals(pullIntoDescriptor.buffer[0], 1);11assert_equals(pullIntoDescriptor.buffer[1], 2);12var rbs = new ReadableByteStream();13var controller = rbs.getController();14var pullIntoDescriptor = {bytesFilled: 0, elementSize: 1, byteLength: 2, byteOffset: 0, buffer: new ArrayBuffer(2), ctor: Uint8Array, type: "bytes"};15controller.enqueue(new Uint8Array([1,2,3,4]));16controller.enqueue(new Uint8Array([5,6,7,8]));17controller.close();18var result = controller.processPullIntoDescriptorsUsingQueue(pullIntoDescriptor);19assert_equals(result, 2);20assert_equals(pullIntoDescriptor.bytesFilled, 2);21assert_equals(pullIntoDescriptor.buffer[0], 1);22assert_equals(pullIntoDescriptor.buffer[1], 2);23controller.respond(1);24assert_equals(controller.byobRequest, undefined);25assert_equals(rbs.state, "readable");26assert_equals(rbs.queue.length, 1);27assert_equals(rbs.queue[0][0], 2);28assert_equals(rbs.queue[0][1], 3);29assert_equals(rbs.queue[0][2], 4);30assert_equals(rbs.queue[0][3], 5);31assert_equals(rbs.queue[0][4], 6);32assert_equals(rbs.queue[0][5], 7);33assert_equals(rbs.queue[0][6], 8);34var rbs = new ReadableByteStream();

Using AI Code Generation

1var ws = new ReadableStream({2    pull: function(controller) {3        var desc = controller.byobRequest.descriptors;4        var result = controller.byobRequest.view;5        var buffer = new ArrayBuffer(16);6        result = new Uint8Array(buffer);7        result[0] = 5;8        result[1] = 6;9        result[2] = 7;10        result[3] = 8;11        result[4] = 9;12        result[5] = 10;13        result[6] = 11;14        result[7] = 12;15        result[8] = 13;16        result[9] = 14;17        result[10] = 15;18        result[11] = 16;19        result[12] = 17;20        result[13] = 18;21        result[14] = 19;22        result[15] = 20;23        controller.byobRequest.respondWithNewView(result);24        controller.close();25    }26});27var reader = ws.getReader({ mode: 'byob' });28var read = reader.read(new Uint8Array(16));29read.then(function(result) {30    assert_array_equals(result.value, [5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20], 'the value read should be as expected');31    assert_true(result.done, 'the stream should be done');32    read = reader.read(new Uint8Array(16));33    return read;34}).then(function(result) {35    assert_array_equals(result.value, [], 'the value read should be as expected');36    assert_true(result.done, 'the stream should be done');37    read = reader.read(new Uint8Array(16));38    return read;39}).then(function(result) {40    assert_array_equals(result.value, [], 'the value read should be as expected');41    assert_true(result.done, 'the stream should be done');42    read = reader.read(new Uint8Array(16));43    return read;44}).then(function(result) {45    assert_array_equals(result.value, [], 'the value read should be as expected');46    assert_true(result.done, 'the stream should be done');

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