@skybloxsystems/ticket-bot/Bot/node_modules/web-streams-polyfill/dist/polyfill.es6.mjs.map

Main

{"version":3,"file":"polyfill.es6.mjs","sources":["../src/stub/symbol.ts","../src/utils.ts","../src/lib/helpers/miscellaneous.ts","../src/lib/helpers/webidl.ts","../src/lib/simple-queue.ts","../src/lib/readable-stream/generic-reader.ts","../src/lib/abstract-ops/internal-methods.ts","../src/stub/number-isfinite.ts","../src/stub/math-trunc.ts","../src/lib/validators/basic.ts","../src/lib/validators/readable-stream.ts","../src/lib/readable-stream/default-reader.ts","../src/target/es5/stub/async-iterator-prototype.ts","../src/lib/readable-stream/async-iterator.ts","../src/stub/number-isnan.ts","../src/lib/abstract-ops/ecmascript.ts","../src/lib/abstract-ops/miscellaneous.ts","../src/lib/abstract-ops/queue-with-sizes.ts","../src/lib/readable-stream/byte-stream-controller.ts","../src/lib/readable-stream/byob-reader.ts","../src/lib/abstract-ops/queuing-strategy.ts","../src/lib/validators/queuing-strategy.ts","../src/lib/validators/underlying-sink.ts","../src/lib/validators/writable-stream.ts","../src/lib/abort-signal.ts","../src/lib/writable-stream.ts","../src/stub/native.ts","../src/stub/dom-exception.ts","../src/lib/readable-stream/pipe.ts","../src/lib/readable-stream/default-controller.ts","../src/lib/readable-stream/tee.ts","../src/lib/validators/underlying-source.ts","../src/lib/validators/reader-options.ts","../src/lib/validators/iterator-options.ts","../src/lib/validators/pipe-options.ts","../src/lib/validators/readable-writable-pair.ts","../src/lib/readable-stream.ts","../src/lib/validators/queuing-strategy-init.ts","../src/lib/byte-length-queuing-strategy.ts","../src/lib/count-queuing-strategy.ts","../src/lib/validators/transformer.ts","../src/lib/transform-stream.ts","../src/polyfill.ts"],"sourcesContent":["/// <reference lib=\"es2015.symbol\" />\n\nconst SymbolPolyfill: (description?: string) => symbol =\n  typeof Symbol === 'function' && typeof Symbol.iterator === 'symbol' ?\n    Symbol :\n    description => `Symbol(${description})` as any as symbol;\n\nexport default SymbolPolyfill;\n","/// <reference lib=\"dom\" />\n\nexport function noop(): undefined {\n  return undefined;\n}\n\nfunction getGlobals() {\n  if (typeof self !== 'undefined') {\n    return self;\n  } else if (typeof window !== 'undefined') {\n    return window;\n  } else if (typeof global !== 'undefined') {\n    return global;\n  }\n  return undefined;\n}\n\nexport const globals = getGlobals();\n","import { noop } from '../../utils';\nimport { AssertionError } from '../../stub/assert';\n\nexport function typeIsObject(x: any): x is object {\n  return (typeof x === 'object' && x !== null) || typeof x === 'function';\n}\n\nexport const rethrowAssertionErrorRejection: (e: any) => void =\n  DEBUG ? e => {\n    // Used throughout the reference implementation, as `.catch(rethrowAssertionErrorRejection)`, to ensure any errors\n    // get shown. There are places in the spec where we do promise transformations and purposefully ignore or don't\n    // expect any errors, but assertion errors are always problematic.\n    if (e && e instanceof AssertionError) {\n      setTimeout(() => {\n        throw e;\n      }, 0);\n    }\n  } : noop;\n","import { globals } from '../../utils';\nimport { rethrowAssertionErrorRejection } from './miscellaneous';\nimport assert from '../../stub/assert';\n\nconst originalPromise = Promise;\nconst originalPromiseThen = Promise.prototype.then;\nconst originalPromiseResolve = Promise.resolve.bind(originalPromise);\nconst originalPromiseReject = Promise.reject.bind(originalPromise);\n\nexport function newPromise<T>(executor: (\n  resolve: (value: T | PromiseLike<T>) => void,\n  reject: (reason?: any) => void\n) => void): Promise<T> {\n  return new originalPromise(executor);\n}\n\nexport function promiseResolvedWith<T>(value: T | PromiseLike<T>): Promise<T> {\n  return originalPromiseResolve(value);\n}\n\nexport function promiseRejectedWith<T = never>(reason: any): Promise<T> {\n  return originalPromiseReject(reason);\n}\n\nexport function PerformPromiseThen<T, TResult1 = T, TResult2 = never>(\n  promise: Promise<T>,\n  onFulfilled?: (value: T) => TResult1 | PromiseLike<TResult1>,\n  onRejected?: (reason: any) => TResult2 | PromiseLike<TResult2>): Promise<TResult1 | TResult2> {\n  // There doesn't appear to be any way to correctly emulate the behaviour from JavaScript, so this is just an\n  // approximation.\n  return originalPromiseThen.call(promise, onFulfilled, onRejected) as Promise<TResult1 | TResult2>;\n}\n\nexport function uponPromise<T>(\n  promise: Promise<T>,\n  onFulfilled?: (value: T) => void | PromiseLike<void>,\n  onRejected?: (reason: any) => void | PromiseLike<void>): void {\n  PerformPromiseThen(\n    PerformPromiseThen(promise, onFulfilled, onRejected),\n    undefined,\n    rethrowAssertionErrorRejection\n  );\n}\n\nexport function uponFulfillment<T>(promise: Promise<T>, onFulfilled: (value: T) => void | PromiseLike<void>): void {\n  uponPromise(promise, onFulfilled);\n}\n\nexport function uponRejection(promise: Promise<unknown>, onRejected: (reason: any) => void | PromiseLike<void>): void {\n  uponPromise(promise, undefined, onRejected);\n}\n\nexport function transformPromiseWith<T, TResult1 = T, TResult2 = never>(\n  promise: Promise<T>,\n  fulfillmentHandler?: (value: T) => TResult1 | PromiseLike<TResult1>,\n  rejectionHandler?: (reason: any) => TResult2 | PromiseLike<TResult2>): Promise<TResult1 | TResult2> {\n  return PerformPromiseThen(promise, fulfillmentHandler, rejectionHandler);\n}\n\nexport function setPromiseIsHandledToTrue(promise: Promise<unknown>): void {\n  PerformPromiseThen(promise, undefined, rethrowAssertionErrorRejection);\n}\n\nexport const queueMicrotask: (fn: () => void) => void = (() => {\n  const globalQueueMicrotask = globals && globals.queueMicrotask;\n  if (typeof globalQueueMicrotask === 'function') {\n    return globalQueueMicrotask;\n  }\n\n  const resolvedPromise = promiseResolvedWith(undefined);\n  return (fn: () => void) => PerformPromiseThen(resolvedPromise, fn);\n})();\n\nexport function reflectCall<T, A extends any[], R>(F: (this: T, ...fnArgs: A) => R, V: T, args: A): R {\n  if (typeof F !== 'function') {\n    throw new TypeError('Argument is not a function');\n  }\n  return Function.prototype.apply.call(F, V, args);\n}\n\nexport function promiseCall<T, A extends any[], R>(F: (this: T, ...fnArgs: A) => R | PromiseLike<R>,\n                                                   V: T,\n                                                   args: A): Promise<R> {\n  assert(typeof F === 'function');\n  assert(V !== undefined);\n  assert(Array.isArray(args));\n  try {\n    return promiseResolvedWith(reflectCall(F, V, args));\n  } catch (value) {\n    return promiseRejectedWith(value);\n  }\n}\n","import assert from '../stub/assert';\n\n// Original from Chromium\n// https://chromium.googlesource.com/chromium/src/+/0aee4434a4dba42a42abaea9bfbc0cd196a63bc1/third_party/blink/renderer/core/streams/SimpleQueue.js\n\nconst QUEUE_MAX_ARRAY_SIZE = 16384;\n\ninterface Node<T> {\n  _elements: T[];\n  _next: Node<T> | undefined;\n}\n\n/**\n * Simple queue structure.\n *\n * Avoids scalability issues with using a packed array directly by using\n * multiple arrays in a linked list and keeping the array size bounded.\n */\nexport class SimpleQueue<T> {\n  private _front: Node<T>;\n  private _back: Node<T>;\n  private _cursor = 0;\n  private _size = 0;\n\n  constructor() {\n    // _front and _back are always defined.\n    this._front = {\n      _elements: [],\n      _next: undefined\n    };\n    this._back = this._front;\n    // The cursor is used to avoid calling Array.shift().\n    // It contains the index of the front element of the array inside the\n    // front-most node. It is always in the range [0, QUEUE_MAX_ARRAY_SIZE).\n    this._cursor = 0;\n    // When there is only one node, size === elements.length - cursor.\n    this._size = 0;\n  }\n\n  get length(): number {\n    return this._size;\n  }\n\n  // For exception safety, this method is structured in order:\n  // 1. Read state\n  // 2. Calculate required state mutations\n  // 3. Perform state mutations\n  push(element: T): void {\n    const oldBack = this._back;\n    let newBack = oldBack;\n    assert(oldBack._next === undefined);\n    if (oldBack._elements.length === QUEUE_MAX_ARRAY_SIZE - 1) {\n      newBack = {\n        _elements: [],\n        _next: undefined\n      };\n    }\n\n    // push() is the mutation most likely to throw an exception, so it\n    // goes first.\n    oldBack._elements.push(element);\n    if (newBack !== oldBack) {\n      this._back = newBack;\n      oldBack._next = newBack;\n    }\n    ++this._size;\n  }\n\n  // Like push(), shift() follows the read -> calculate -> mutate pattern for\n  // exception safety.\n  shift(): T {\n    assert(this._size > 0); // must not be called on an empty queue\n\n    const oldFront = this._front;\n    let newFront = oldFront;\n    const oldCursor = this._cursor;\n    let newCursor = oldCursor + 1;\n\n    const elements = oldFront._elements;\n    const element = elements[oldCursor];\n\n    if (newCursor === QUEUE_MAX_ARRAY_SIZE) {\n      assert(elements.length === QUEUE_MAX_ARRAY_SIZE);\n      assert(oldFront._next !== undefined);\n      newFront = oldFront._next!;\n      newCursor = 0;\n    }\n\n    // No mutations before this point.\n    --this._size;\n    this._cursor = newCursor;\n    if (oldFront !== newFront) {\n      this._front = newFront;\n    }\n\n    // Permit shifted element to be garbage collected.\n    elements[oldCursor] = undefined!;\n\n    return element;\n  }\n\n  // The tricky thing about forEach() is that it can be called\n  // re-entrantly. The queue may be mutated inside the callback. It is easy to\n  // see that push() within the callback has no negative effects since the end\n  // of the queue is checked for on every iteration. If shift() is called\n  // repeatedly within the callback then the next iteration may return an\n  // element that has been removed. In this case the callback will be called\n  // with undefined values until we either \"catch up\" with elements that still\n  // exist or reach the back of the queue.\n  forEach(callback: (element: T) => void): void {\n    let i = this._cursor;\n    let node = this._front;\n    let elements = node._elements;\n    while (i !== elements.length || node._next !== undefined) {\n      if (i === elements.length) {\n        assert(node._next !== undefined);\n        assert(i === QUEUE_MAX_ARRAY_SIZE);\n        node = node._next!;\n        elements = node._elements;\n        i = 0;\n        if (elements.length === 0) {\n          break;\n        }\n      }\n      callback(elements[i]);\n      ++i;\n    }\n  }\n\n  // Return the element that would be returned if shift() was called now,\n  // without modifying the queue.\n  peek(): T {\n    assert(this._size > 0); // must not be called on an empty queue\n\n    const front = this._front;\n    const cursor = this._cursor;\n    return front._elements[cursor];\n  }\n}\n","import assert from '../../stub/assert';\nimport { ReadableStream, ReadableStreamCancel, ReadableStreamReader } from '../readable-stream';\nimport { newPromise, setPromiseIsHandledToTrue } from '../helpers/webidl';\n\nexport function ReadableStreamReaderGenericInitialize<R>(reader: ReadableStreamReader<R>, stream: ReadableStream<R>) {\n  reader._ownerReadableStream = stream;\n  stream._reader = reader;\n\n  if (stream._state === 'readable') {\n    defaultReaderClosedPromiseInitialize(reader);\n  } else if (stream._state === 'closed') {\n    defaultReaderClosedPromiseInitializeAsResolved(reader);\n  } else {\n    assert(stream._state === 'errored');\n\n    defaultReaderClosedPromiseInitializeAsRejected(reader, stream._storedError);\n  }\n}\n\n// A client of ReadableStreamDefaultReader and ReadableStreamBYOBReader may use these functions directly to bypass state\n// check.\n\nexport function ReadableStreamReaderGenericCancel(reader: ReadableStreamReader<any>, reason: any): Promise<undefined> {\n  const stream = reader._ownerReadableStream;\n  assert(stream !== undefined);\n  return ReadableStreamCancel(stream, reason);\n}\n\nexport function ReadableStreamReaderGenericRelease(reader: ReadableStreamReader<any>) {\n  assert(reader._ownerReadableStream !== undefined);\n  assert(reader._ownerReadableStream._reader === reader);\n\n  if (reader._ownerReadableStream._state === 'readable') {\n    defaultReaderClosedPromiseReject(\n      reader,\n      new TypeError(`Reader was released and can no longer be used to monitor the stream's closedness`));\n  } else {\n    defaultReaderClosedPromiseResetToRejected(\n      reader,\n      new TypeError(`Reader was released and can no longer be used to monitor the stream's closedness`));\n  }\n\n  reader._ownerReadableStream._reader = undefined;\n  reader._ownerReadableStream = undefined!;\n}\n\n// Helper functions for the readers.\n\nexport function readerLockException(name: string): TypeError {\n  return new TypeError('Cannot ' + name + ' a stream using a released reader');\n}\n\n// Helper functions for the ReadableStreamDefaultReader.\n\nexport function defaultReaderClosedPromiseInitialize(reader: ReadableStreamReader<any>) {\n  reader._closedPromise = newPromise((resolve, reject) => {\n    reader._closedPromise_resolve = resolve;\n    reader._closedPromise_reject = reject;\n  });\n}\n\nexport function defaultReaderClosedPromiseInitializeAsRejected(reader: ReadableStreamReader<any>, reason: any) {\n  defaultReaderClosedPromiseInitialize(reader);\n  defaultReaderClosedPromiseReject(reader, reason);\n}\n\nexport function defaultReaderClosedPromiseInitializeAsResolved(reader: ReadableStreamReader<any>) {\n  defaultReaderClosedPromiseInitialize(reader);\n  defaultReaderClosedPromiseResolve(reader);\n}\n\nexport function defaultReaderClosedPromiseReject(reader: ReadableStreamReader<any>, reason: any) {\n  if (reader._closedPromise_reject === undefined) {\n    return;\n  }\n\n  setPromiseIsHandledToTrue(reader._closedPromise);\n  reader._closedPromise_reject(reason);\n  reader._closedPromise_resolve = undefined;\n  reader._closedPromise_reject = undefined;\n}\n\nexport function defaultReaderClosedPromiseResetToRejected(reader: ReadableStreamReader<any>, reason: any) {\n  assert(reader._closedPromise_resolve === undefined);\n  assert(reader._closedPromise_reject === undefined);\n\n  defaultReaderClosedPromiseInitializeAsRejected(reader, reason);\n}\n\nexport function defaultReaderClosedPromiseResolve(reader: ReadableStreamReader<any>) {\n  if (reader._closedPromise_resolve === undefined) {\n    return;\n  }\n\n  reader._closedPromise_resolve(undefined);\n  reader._closedPromise_resolve = undefined;\n  reader._closedPromise_reject = undefined;\n}\n","export const AbortSteps = Symbol('[[AbortSteps]]');\nexport const ErrorSteps = Symbol('[[ErrorSteps]]');\nexport const CancelSteps = Symbol('[[CancelSteps]]');\nexport const PullSteps = Symbol('[[PullSteps]]');\n","/// <reference lib=\"es2015.core\" />\n\n// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isFinite#Polyfill\nconst NumberIsFinite: typeof Number.isFinite = Number.isFinite || function (x) {\n  return typeof x === 'number' && isFinite(x);\n};\n\nexport default NumberIsFinite;\n","/// <reference lib=\"es2015.core\" />\n\n// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/trunc#Polyfill\nconst MathTrunc: typeof Math.trunc = Math.trunc || function (v) {\n  return v < 0 ? Math.ceil(v) : Math.floor(v);\n};\n\nexport default MathTrunc;\n","import NumberIsFinite from '../../stub/number-isfinite';\nimport MathTrunc from '../../stub/math-trunc';\n\n// https://heycam.github.io/webidl/#idl-dictionaries\nexport function isDictionary(x: any): x is object | null {\n  return typeof x === 'object' || typeof x === 'function';\n}\n\nexport function assertDictionary(obj: unknown,\n                                 context: string): asserts obj is object | null | undefined {\n  if (obj !== undefined && !isDictionary(obj)) {\n    throw new TypeError(`${context} is not an object.`);\n  }\n}\n\nexport type AnyFunction = (...args: any[]) => any;\n\n// https://heycam.github.io/webidl/#idl-callback-functions\nexport function assertFunction(x: unknown, context: string): asserts x is AnyFunction {\n  if (typeof x !== 'function') {\n    throw new TypeError(`${context} is not a function.`);\n  }\n}\n\n// https://heycam.github.io/webidl/#idl-object\nexport function isObject(x: any): x is object {\n  return (typeof x === 'object' && x !== null) || typeof x === 'function';\n}\n\nexport function assertObject(x: unknown,\n                             context: string): asserts x is object {\n  if (!isObject(x)) {\n    throw new TypeError(`${context} is not an object.`);\n  }\n}\n\nexport function assertRequiredArgument<T extends any>(x: T | undefined,\n                                                      position: number,\n                                                      context: string): asserts x is T {\n  if (x === undefined) {\n    throw new TypeError(`Parameter ${position} is required in '${context}'.`);\n  }\n}\n\nexport function assertRequiredField<T extends any>(x: T | undefined,\n                                                   field: string,\n                                                   context: string): asserts x is T {\n  if (x === undefined) {\n    throw new TypeError(`${field} is required in '${context}'.`);\n  }\n}\n\n// https://heycam.github.io/webidl/#idl-unrestricted-double\nexport function convertUnrestrictedDouble(value: unknown): number {\n  return Number(value);\n}\n\nfunction censorNegativeZero(x: number): number {\n  return x === 0 ? 0 : x;\n}\n\nfunction integerPart(x: number): number {\n  return censorNegativeZero(MathTrunc(x));\n}\n\n// https://heycam.github.io/webidl/#idl-unsigned-long-long\nexport function convertUnsignedLongLongWithEnforceRange(value: unknown, context: string): number {\n  const lowerBound = 0;\n  const upperBound = Number.MAX_SAFE_INTEGER;\n\n  let x = Number(value);\n  x = censorNegativeZero(x);\n\n  if (!NumberIsFinite(x)) {\n    throw new TypeError(`${context} is not a finite number`);\n  }\n\n  x = integerPart(x);\n\n  if (x < lowerBound || x > upperBound) {\n    throw new TypeError(`${context} is outside the accepted range of ${lowerBound} to ${upperBound}, inclusive`);\n  }\n\n  if (!NumberIsFinite(x) || x === 0) {\n    return 0;\n  }\n\n  // TODO Use BigInt if supported?\n  // let xBigInt = BigInt(integerPart(x));\n  // xBigInt = BigInt.asUintN(64, xBigInt);\n  // return Number(xBigInt);\n\n  return x;\n}\n","import { IsReadableStream, ReadableStream } from '../readable-stream';\n\nexport function assertReadableStream(x: unknown, context: string): asserts x is ReadableStream {\n  if (!IsReadableStream(x)) {\n    throw new TypeError(`${context} is not a ReadableStream.`);\n  }\n}\n","import assert from '../../stub/assert';\nimport { SimpleQueue } from '../simple-queue';\nimport {\n  ReadableStreamReaderGenericCancel,\n  ReadableStreamReaderGenericInitialize,\n  ReadableStreamReaderGenericRelease,\n  readerLockException\n} from './generic-reader';\nimport { IsReadableStreamLocked, ReadableStream } from '../readable-stream';\nimport { typeIsObject } from '../helpers/miscellaneous';\nimport { PullSteps } from '../abstract-ops/internal-methods';\nimport { newPromise, promiseRejectedWith } from '../helpers/webidl';\nimport { assertRequiredArgument } from '../validators/basic';\nimport { assertReadableStream } from '../validators/readable-stream';\n\n/**\n * A result returned by {@link ReadableStreamDefaultReader.read}.\n *\n * @public\n */\nexport type ReadableStreamDefaultReadResult<T> = {\n  done: false;\n  value: T;\n} | {\n  done: true;\n  value?: undefined;\n}\n\n// Abstract operations for the ReadableStream.\n\nexport function AcquireReadableStreamDefaultReader<R>(stream: ReadableStream): ReadableStreamDefaultReader<R> {\n  return new ReadableStreamDefaultReader(stream);\n}\n\n// ReadableStream API exposed for controllers.\n\nexport function ReadableStreamAddReadRequest<R>(stream: ReadableStream<R>,\n                                                readRequest: ReadRequest<R>): void {\n  assert(IsReadableStreamDefaultReader(stream._reader));\n  assert(stream._state === 'readable');\n\n  (stream._reader! as ReadableStreamDefaultReader<R>)._readRequests.push(readRequest);\n}\n\nexport function ReadableStreamFulfillReadRequest<R>(stream: ReadableStream<R>, chunk: R | undefined, done: boolean) {\n  const reader = stream._reader as ReadableStreamDefaultReader<R>;\n\n  assert(reader._readRequests.length > 0);\n\n  const readRequest = reader._readRequests.shift()!;\n  if (done) {\n    readRequest._closeSteps();\n  } else {\n    readRequest._chunkSteps(chunk!);\n  }\n}\n\nexport function ReadableStreamGetNumReadRequests<R>(stream: ReadableStream<R>): number {\n  return (stream._reader as ReadableStreamDefaultReader<R>)._readRequests.length;\n}\n\nexport function ReadableStreamHasDefaultReader(stream: ReadableStream): boolean {\n  const reader = stream._reader;\n\n  if (reader === undefined) {\n    return false;\n  }\n\n  if (!IsReadableStreamDefaultReader(reader)) {\n    return false;\n  }\n\n  return true;\n}\n\n// Readers\n\nexport interface ReadRequest<R> {\n  _chunkSteps(chunk: R): void;\n\n  _closeSteps(): void;\n\n  _errorSteps(e: any): void;\n}\n\n/**\n * A default reader vended by a {@link ReadableStream}.\n *\n * @public\n */\nexport class ReadableStreamDefaultReader<R = any> {\n  /** @internal */\n  _ownerReadableStream!: ReadableStream<R>;\n  /** @internal */\n  _closedPromise!: Promise<undefined>;\n  /** @internal */\n  _closedPromise_resolve?: (value?: undefined) => void;\n  /** @internal */\n  _closedPromise_reject?: (reason: any) => void;\n  /** @internal */\n  _readRequests: SimpleQueue<ReadRequest<R>>;\n\n  constructor(stream: ReadableStream<R>) {\n    assertRequiredArgument(stream, 1, 'ReadableStreamDefaultReader');\n    assertReadableStream(stream, 'First parameter');\n\n    if (IsReadableStreamLocked(stream)) {\n      throw new TypeError('This stream has already been locked for exclusive reading by another reader');\n    }\n\n    ReadableStreamReaderGenericInitialize(this, stream);\n\n    this._readRequests = new SimpleQueue();\n  }\n\n  /**\n   * Returns a promise that will be fulfilled when the stream becomes closed,\n   * or rejected if the stream ever errors or the reader's lock is released before the stream finishes closing.\n   */\n  get closed(): Promise<undefined> {\n    if (!IsReadableStreamDefaultReader(this)) {\n      return promiseRejectedWith(defaultReaderBrandCheckException('closed'));\n    }\n\n    return this._closedPromise;\n  }\n\n  /**\n   * If the reader is active, behaves the same as {@link ReadableStream.cancel | stream.cancel(reason)}.\n   */\n  cancel(reason: any = undefined): Promise<void> {\n    if (!IsReadableStreamDefaultReader(this)) {\n      return promiseRejectedWith(defaultReaderBrandCheckException('cancel'));\n    }\n\n    if (this._ownerReadableStream === undefined) {\n      return promiseRejectedWith(readerLockException('cancel'));\n    }\n\n    return ReadableStreamReaderGenericCancel(this, reason);\n  }\n\n  /**\n   * Returns a promise that allows access to the next chunk from the stream's internal queue, if available.\n   *\n   * If reading a chunk causes the queue to become empty, more data will be pulled from the underlying source.\n   */\n  read(): Promise<ReadableStreamDefaultReadResult<R>> {\n    if (!IsReadableStreamDefaultReader(this)) {\n      return promiseRejectedWith(defaultReaderBrandCheckException('read'));\n    }\n\n    if (this._ownerReadableStream === undefined) {\n      return promiseRejectedWith(readerLockException('read from'));\n    }\n\n    let resolvePromise!: (result: ReadableStreamDefaultReadResult<R>) => void;\n    let rejectPromise!: (reason: any) => void;\n    const promise = newPromise<ReadableStreamDefaultReadResult<R>>((resolve, reject) => {\n      resolvePromise = resolve;\n      rejectPromise = reject;\n    });\n    const readRequest: ReadRequest<R> = {\n      _chunkSteps: chunk => resolvePromise({ value: chunk, done: false }),\n      _closeSteps: () => resolvePromise({ value: undefined, done: true }),\n      _errorSteps: e => rejectPromise(e)\n    };\n    ReadableStreamDefaultReaderRead(this, readRequest);\n    return promise;\n  }\n\n  /**\n   * Releases the reader's lock on the corresponding stream. After the lock is released, the reader is no longer active.\n   * If the associated stream is errored when the lock is released, the reader will appear errored in the same way\n   * from now on; otherwise, the reader will appear closed.\n   *\n   * A reader's lock cannot be released while it still has a pending read request, i.e., if a promise returned by\n   * the reader's {@link ReadableStreamDefaultReader.read | read()} method has not yet been settled. Attempting to\n   * do so will throw a `TypeError` and leave the reader locked to the stream.\n   */\n  releaseLock(): void {\n    if (!IsReadableStreamDefaultReader(this)) {\n      throw defaultReaderBrandCheckException('releaseLock');\n    }\n\n    if (this._ownerReadableStream === undefined) {\n      return;\n    }\n\n    if (this._readRequests.length > 0) {\n      throw new TypeError('Tried to release a reader lock when that reader has pending read() calls un-settled');\n    }\n\n    ReadableStreamReaderGenericRelease(this);\n  }\n}\n\nObject.defineProperties(ReadableStreamDefaultReader.prototype, {\n  cancel: { enumerable: true },\n  read: { enumerable: true },\n  releaseLock: { enumerable: true },\n  closed: { enumerable: true }\n});\nif (typeof Symbol.toStringTag === 'symbol') {\n  Object.defineProperty(ReadableStreamDefaultReader.prototype, Symbol.toStringTag, {\n    value: 'ReadableStreamDefaultReader',\n    configurable: true\n  });\n}\n\n// Abstract operations for the readers.\n\nexport function IsReadableStreamDefaultReader<R = any>(x: any): x is ReadableStreamDefaultReader<R> {\n  if (!typeIsObject(x)) {\n    return false;\n  }\n\n  if (!Object.prototype.hasOwnProperty.call(x, '_readRequests')) {\n    return false;\n  }\n\n  return x instanceof ReadableStreamDefaultReader;\n}\n\nexport function ReadableStreamDefaultReaderRead<R>(reader: ReadableStreamDefaultReader<R>,\n                                                   readRequest: ReadRequest<R>): void {\n  const stream = reader._ownerReadableStream;\n\n  assert(stream !== undefined);\n\n  stream._disturbed = true;\n\n  if (stream._state === 'closed') {\n    readRequest._closeSteps();\n  } else if (stream._state === 'errored') {\n    readRequest._errorSteps(stream._storedError);\n  } else {\n    assert(stream._state === 'readable');\n    stream._readableStreamController[PullSteps](readRequest as ReadRequest<any>);\n  }\n}\n\n// Helper functions for the ReadableStreamDefaultReader.\n\nfunction defaultReaderBrandCheckException(name: string): TypeError {\n  return new TypeError(\n    `ReadableStreamDefaultReader.prototype.${name} can only be used on a ReadableStreamDefaultReader`);\n}\n","/// <reference lib=\"es2018.asynciterable\" />\n\nexport let AsyncIteratorPrototype: AsyncIterable<any> | undefined;\n\nif (typeof Symbol.asyncIterator === 'symbol') {\n  // We're running inside a ES2018+ environment, but we're compiling to an older syntax.\n  // We cannot access %AsyncIteratorPrototype% without non-ES2018 syntax, but we can re-create it.\n  AsyncIteratorPrototype = {\n    // 25.1.3.1 %AsyncIteratorPrototype% [ @@asyncIterator ] ( )\n    // https://tc39.github.io/ecma262/#sec-asynciteratorprototype-asynciterator\n    [Symbol.asyncIterator](this: AsyncIterator<any>) {\n      return this;\n    }\n  };\n  Object.defineProperty(AsyncIteratorPrototype, Symbol.asyncIterator, { enumerable: false });\n}\n","/// <reference lib=\"es2018.asynciterable\" />\n\nimport { ReadableStream } from '../readable-stream';\nimport {\n  AcquireReadableStreamDefaultReader,\n  ReadableStreamDefaultReader,\n  ReadableStreamDefaultReaderRead,\n  ReadableStreamDefaultReadResult,\n  ReadRequest\n} from './default-reader';\nimport {\n  ReadableStreamReaderGenericCancel,\n  ReadableStreamReaderGenericRelease,\n  readerLockException\n} from './generic-reader';\nimport assert from '../../stub/assert';\nimport { AsyncIteratorPrototype } from '@@target/stub/async-iterator-prototype';\nimport { typeIsObject } from '../helpers/miscellaneous';\nimport {\n  newPromise,\n  promiseRejectedWith,\n  promiseResolvedWith,\n  queueMicrotask,\n  transformPromiseWith\n} from '../helpers/webidl';\n\n/**\n * An async iterator returned by {@link ReadableStream.values}.\n *\n * @public\n */\nexport interface ReadableStreamAsyncIterator<R> extends AsyncIterator<R> {\n  next(): Promise<IteratorResult<R, undefined>>;\n\n  return(value?: any): Promise<IteratorResult<any>>;\n}\n\nexport class ReadableStreamAsyncIteratorImpl<R> {\n  private readonly _reader: ReadableStreamDefaultReader<R>;\n  private readonly _preventCancel: boolean;\n  private _ongoingPromise: Promise<ReadableStreamDefaultReadResult<R>> | undefined = undefined;\n  private _isFinished = false;\n\n  constructor(reader: ReadableStreamDefaultReader<R>, preventCancel: boolean) {\n    this._reader = reader;\n    this._preventCancel = preventCancel;\n  }\n\n  next(): Promise<ReadableStreamDefaultReadResult<R>> {\n    const nextSteps = () => this._nextSteps();\n    this._ongoingPromise = this._ongoingPromise ?\n      transformPromiseWith(this._ongoingPromise, nextSteps, nextSteps) :\n      nextSteps();\n    return this._ongoingPromise;\n  }\n\n  return(value: any): Promise<ReadableStreamDefaultReadResult<any>> {\n    const returnSteps = () => this._returnSteps(value);\n    return this._ongoingPromise ?\n      transformPromiseWith(this._ongoingPromise, returnSteps, returnSteps) :\n      returnSteps();\n  }\n\n  private _nextSteps(): Promise<ReadableStreamDefaultReadResult<R>> {\n    if (this._isFinished) {\n      return Promise.resolve({ value: undefined, done: true });\n    }\n\n    const reader = this._reader;\n    if (reader._ownerReadableStream === undefined) {\n      return promiseRejectedWith(readerLockException('iterate'));\n    }\n\n    let resolvePromise!: (result: ReadableStreamDefaultReadResult<R>) => void;\n    let rejectPromise!: (reason: any) => void;\n    const promise = newPromise<ReadableStreamDefaultReadResult<R>>((resolve, reject) => {\n      resolvePromise = resolve;\n      rejectPromise = reject;\n    });\n    const readRequest: ReadRequest<R> = {\n      _chunkSteps: chunk => {\n        this._ongoingPromise = undefined;\n        // This needs to be delayed by one microtask, otherwise we stop pulling too early which breaks a test.\n        // FIXME Is this a bug in the specification, or in the test?\n        queueMicrotask(() => resolvePromise({ value: chunk, done: false }));\n      },\n      _closeSteps: () => {\n        this._ongoingPromise = undefined;\n        this._isFinished = true;\n        ReadableStreamReaderGenericRelease(reader);\n        resolvePromise({ value: undefined, done: true });\n      },\n      _errorSteps: reason => {\n        this._ongoingPromise = undefined;\n        this._isFinished = true;\n        ReadableStreamReaderGenericRelease(reader);\n        rejectPromise(reason);\n      }\n    };\n    ReadableStreamDefaultReaderRead(reader, readRequest);\n    return promise;\n  }\n\n  private _returnSteps(value: any): Promise<ReadableStreamDefaultReadResult<any>> {\n    if (this._isFinished) {\n      return Promise.resolve({ value, done: true });\n    }\n    this._isFinished = true;\n\n    const reader = this._reader;\n    if (reader._ownerReadableStream === undefined) {\n      return promiseRejectedWith(readerLockException('finish iterating'));\n    }\n\n    assert(reader._readRequests.length === 0);\n\n    if (!this._preventCancel) {\n      const result = ReadableStreamReaderGenericCancel(reader, value);\n      ReadableStreamReaderGenericRelease(reader);\n      return transformPromiseWith(result, () => ({ value, done: true }));\n    }\n\n    ReadableStreamReaderGenericRelease(reader);\n    return promiseResolvedWith({ value, done: true });\n  }\n}\n\ndeclare class ReadableStreamAsyncIteratorInstance<R> implements ReadableStreamAsyncIterator<R> {\n  /** @interal */\n  _asyncIteratorImpl: ReadableStreamAsyncIteratorImpl<R>;\n\n  next(): Promise<IteratorResult<R, undefined>>;\n\n  return(value?: any): Promise<IteratorResult<any>>;\n}\n\nconst ReadableStreamAsyncIteratorPrototype: ReadableStreamAsyncIteratorInstance<any> = {\n  next(this: ReadableStreamAsyncIteratorInstance<any>): Promise<ReadableStreamDefaultReadResult<any>> {\n    if (!IsReadableStreamAsyncIterator(this)) {\n      return promiseRejectedWith(streamAsyncIteratorBrandCheckException('next'));\n    }\n    return this._asyncIteratorImpl.next();\n  },\n\n  return(this: ReadableStreamAsyncIteratorInstance<any>, value: any): Promise<ReadableStreamDefaultReadResult<any>> {\n    if (!IsReadableStreamAsyncIterator(this)) {\n      return promiseRejectedWith(streamAsyncIteratorBrandCheckException('return'));\n    }\n    return this._asyncIteratorImpl.return(value);\n  }\n} as any;\nif (AsyncIteratorPrototype !== undefined) {\n  Object.setPrototypeOf(ReadableStreamAsyncIteratorPrototype, AsyncIteratorPrototype);\n}\n\n// Abstract operations for the ReadableStream.\n\nexport function AcquireReadableStreamAsyncIterator<R>(stream: ReadableStream<R>,\n                                                      preventCancel: boolean): ReadableStreamAsyncIterator<R> {\n  const reader = AcquireReadableStreamDefaultReader<R>(stream);\n  const impl = new ReadableStreamAsyncIteratorImpl(reader, preventCancel);\n  const iterator: ReadableStreamAsyncIteratorInstance<R> = Object.create(ReadableStreamAsyncIteratorPrototype);\n  iterator._asyncIteratorImpl = impl;\n  return iterator;\n}\n\nfunction IsReadableStreamAsyncIterator<R = any>(x: any): x is ReadableStreamAsyncIterator<R> {\n  if (!typeIsObject(x)) {\n    return false;\n  }\n\n  if (!Object.prototype.hasOwnProperty.call(x, '_asyncIteratorImpl')) {\n    return false;\n  }\n\n  try {\n    // noinspection SuspiciousTypeOfGuard\n    return (x as ReadableStreamAsyncIteratorInstance<any>)._asyncIteratorImpl instanceof\n      ReadableStreamAsyncIteratorImpl;\n  } catch {\n    return false;\n  }\n}\n\n// Helper functions for the ReadableStream.\n\nfunction streamAsyncIteratorBrandCheckException(name: string): TypeError {\n  return new TypeError(`ReadableStreamAsyncIterator.${name} can only be used on a ReadableSteamAsyncIterator`);\n}\n","/// <reference lib=\"es2015.core\" />\n\n// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isNaN#Polyfill\nconst NumberIsNaN: typeof Number.isNaN = Number.isNaN || function (x) {\n  // eslint-disable-next-line no-self-compare\n  return x !== x;\n};\n\nexport default NumberIsNaN;\n","export function CreateArrayFromList<T extends any[]>(elements: T): T {\n  // We use arrays to represent lists, so this is basically a no-op.\n  // Do a slice though just in case we happen to depend on the unique-ness.\n  return elements.slice() as T;\n}\n\nexport function CopyDataBlockBytes(dest: ArrayBuffer,\n                                   destOffset: number,\n                                   src: ArrayBuffer,\n                                   srcOffset: number,\n                                   n: number) {\n  new Uint8Array(dest).set(new Uint8Array(src, srcOffset, n), destOffset);\n}\n\n// Not implemented correctly\nexport function TransferArrayBuffer<T extends ArrayBufferLike>(O: T): T {\n  return O;\n}\n\n// Not implemented correctly\n// eslint-disable-next-line @typescript-eslint/no-unused-vars\nexport function CanTransferArrayBuffer(O: ArrayBufferLike): boolean {\n  return true;\n}\n\n// Not implemented correctly\n// eslint-disable-next-line @typescript-eslint/no-unused-vars\nexport function IsDetachedBuffer(O: ArrayBufferLike): boolean {\n  return false;\n}\n\nexport function ArrayBufferSlice(buffer: ArrayBufferLike, begin: number, end: number): ArrayBufferLike {\n  // ArrayBuffer.prototype.slice is not available on IE10\n  // https://www.caniuse.com/mdn-javascript_builtins_arraybuffer_slice\n  if (buffer.slice) {\n    return buffer.slice(begin, end);\n  }\n  const length = end - begin;\n  const slice = new ArrayBuffer(length);\n  CopyDataBlockBytes(slice, 0, buffer, begin, length);\n  return slice;\n}\n","import NumberIsNaN from '../../stub/number-isnan';\nimport { ArrayBufferSlice } from './ecmascript';\n\nexport function IsNonNegativeNumber(v: number): boolean {\n  if (typeof v !== 'number') {\n    return false;\n  }\n\n  if (NumberIsNaN(v)) {\n    return false;\n  }\n\n  if (v < 0) {\n    return false;\n  }\n\n  return true;\n}\n\nexport function CloneAsUint8Array(O: ArrayBufferView): Uint8Array {\n  const buffer = ArrayBufferSlice(O.buffer, O.byteOffset, O.byteOffset + O.byteLength);\n  return new Uint8Array(buffer);\n}\n","import assert from '../../stub/assert';\nimport { SimpleQueue } from '../simple-queue';\nimport { IsNonNegativeNumber } from './miscellaneous';\n\nexport interface QueueContainer<T> {\n  _queue: SimpleQueue<T>;\n  _queueTotalSize: number;\n}\n\nexport interface QueuePair<T> {\n  value: T;\n  size: number;\n}\n\nexport function DequeueValue<T>(container: QueueContainer<QueuePair<T>>): T {\n  assert('_queue' in container && '_queueTotalSize' in container);\n  assert(container._queue.length > 0);\n\n  const pair = container._queue.shift()!;\n  container._queueTotalSize -= pair.size;\n  if (container._queueTotalSize < 0) {\n    container._queueTotalSize = 0;\n  }\n\n  return pair.value;\n}\n\nexport function EnqueueValueWithSize<T>(container: QueueContainer<QueuePair<T>>, value: T, size: number) {\n  assert('_queue' in container && '_queueTotalSize' in container);\n\n  if (!IsNonNegativeNumber(size) || size === Infinity) {\n    throw new RangeError('Size must be a finite, non-NaN, non-negative number.');\n  }\n\n  container._queue.push({ value, size });\n  container._queueTotalSize += size;\n}\n\nexport function PeekQueueValue<T>(container: QueueContainer<QueuePair<T>>): T {\n  assert('_queue' in container && '_queueTotalSize' in container);\n  assert(container._queue.length > 0);\n\n  const pair = container._queue.peek();\n  return pair.value;\n}\n\nexport function ResetQueue<T>(container: QueueContainer<T>) {\n  assert('_queue' in container && '_queueTotalSize' in container);\n\n  container._queue = new SimpleQueue<T>();\n  container._queueTotalSize = 0;\n}\n","import assert from '../../stub/assert';\nimport { SimpleQueue } from '../simple-queue';\nimport { ResetQueue } from '../abstract-ops/queue-with-sizes';\nimport {\n  ReadableStreamAddReadRequest,\n  ReadableStreamFulfillReadRequest,\n  ReadableStreamGetNumReadRequests,\n  ReadableStreamHasDefaultReader,\n  ReadRequest\n} from './default-reader';\nimport {\n  ReadableStreamAddReadIntoRequest,\n  ReadableStreamFulfillReadIntoRequest,\n  ReadableStreamGetNumReadIntoRequests,\n  ReadableStreamHasBYOBReader,\n  ReadIntoRequest\n} from './byob-reader';\nimport NumberIsInteger from '../../stub/number-isinteger';\nimport {\n  IsReadableStreamLocked,\n  ReadableByteStream,\n  ReadableStreamClose,\n  ReadableStreamError\n} from '../readable-stream';\nimport { ValidatedUnderlyingByteSource } from './underlying-source';\nimport { typeIsObject } from '../helpers/miscellaneous';\nimport {\n  ArrayBufferSlice,\n  CanTransferArrayBuffer,\n  CopyDataBlockBytes,\n  IsDetachedBuffer,\n  TransferArrayBuffer\n} from '../abstract-ops/ecmascript';\nimport { CancelSteps, PullSteps } from '../abstract-ops/internal-methods';\nimport { promiseResolvedWith, uponPromise } from '../helpers/webidl';\nimport { assertRequiredArgument, convertUnsignedLongLongWithEnforceRange } from '../validators/basic';\n\n/**\n * A pull-into request in a {@link ReadableByteStreamController}.\n *\n * @public\n */\nexport class ReadableStreamBYOBRequest {\n  /** @internal */\n  _associatedReadableByteStreamController!: ReadableByteStreamController;\n  /** @internal */\n  _view!: ArrayBufferView | null;\n\n  private constructor() {\n    throw new TypeError('Illegal constructor');\n  }\n\n  /**\n   * Returns the view for writing in to, or `null` if the BYOB request has already been responded to.\n   */\n  get view(): ArrayBufferView | null {\n    if (!IsReadableStreamBYOBRequest(this)) {\n      throw byobRequestBrandCheckException('view');\n    }\n\n    return this._view;\n  }\n\n  /**\n   * Indicates to the associated readable byte stream that `bytesWritten` bytes were written into\n   * {@link ReadableStreamBYOBRequest.view | view}, causing the result be surfaced to the consumer.\n   *\n   * After this method is called, {@link ReadableStreamBYOBRequest.view | view} will be transferred and no longer\n   * modifiable.\n   */\n  respond(bytesWritten: number): void;\n  respond(bytesWritten: number | undefined): void {\n    if (!IsReadableStreamBYOBRequest(this)) {\n      throw byobRequestBrandCheckException('respond');\n    }\n    assertRequiredArgument(bytesWritten, 1, 'respond');\n    bytesWritten = convertUnsignedLongLongWithEnforceRange(bytesWritten, 'First parameter');\n\n    if (this._associatedReadableByteStreamController === undefined) {\n      throw new TypeError('This BYOB request has been invalidated');\n    }\n\n    if (IsDetachedBuffer(this._view!.buffer)) {\n      throw new TypeError(`The BYOB request's buffer has been detached and so cannot be used as a response`);\n    }\n\n    assert(this._view!.byteLength > 0);\n    assert(this._view!.buffer.byteLength > 0);\n\n    ReadableByteStreamControllerRespond(this._associatedReadableByteStreamController, bytesWritten);\n  }\n\n  /**\n   * Indicates to the associated readable byte stream that instead of writing into\n   * {@link ReadableStreamBYOBRequest.view | view}, the underlying byte source is providing a new `ArrayBufferView`,\n   * which will be given to the consumer of the readable byte stream.\n   *\n   * After this method is called, `view` will be transferred and no longer modifiable.\n   */\n  respondWithNewView(view: ArrayBufferView): void;\n  respondWithNewView(view: ArrayBufferView | undefined): void {\n    if (!IsReadableStreamBYOBRequest(this)) {\n      throw byobRequestBrandCheckException('respondWithNewView');\n    }\n    assertRequiredArgument(view, 1, 'respondWithNewView');\n\n    if (!ArrayBuffer.isView(view)) {\n      throw new TypeError('You can only respond with array buffer views');\n    }\n\n    if (this._associatedReadableByteStreamController === undefined) {\n      throw new TypeError('This BYOB request has been invalidated');\n    }\n\n    if (IsDetachedBuffer(view.buffer)) {\n      throw new TypeError('The given view\\'s buffer has been detached and so cannot be used as a response');\n    }\n\n    ReadableByteStreamControllerRespondWithNewView(this._associatedReadableByteStreamController, view);\n  }\n}\n\nObject.defineProperties(ReadableStreamBYOBRequest.prototype, {\n  respond: { enumerable: true },\n  respondWithNewView: { enumerable: true },\n  view: { enumerable: true }\n});\nif (typeof Symbol.toStringTag === 'symbol') {\n  Object.defineProperty(ReadableStreamBYOBRequest.prototype, Symbol.toStringTag, {\n    value: 'ReadableStreamBYOBRequest',\n    configurable: true\n  });\n}\n\ninterface ArrayBufferViewConstructor<T extends ArrayBufferView = ArrayBufferView> {\n  new(buffer: ArrayBufferLike, byteOffset: number, length?: number): T;\n\n  readonly prototype: T;\n  readonly BYTES_PER_ELEMENT: number;\n}\n\ninterface ByteQueueElement {\n  buffer: ArrayBufferLike;\n  byteOffset: number;\n  byteLength: number;\n}\n\ntype PullIntoDescriptor<T extends ArrayBufferView = ArrayBufferView> =\n  DefaultPullIntoDescriptor\n  | BYOBPullIntoDescriptor<T>;\n\ninterface DefaultPullIntoDescriptor {\n  buffer: ArrayBufferLike;\n  bufferByteLength: number;\n  byteOffset: number;\n  byteLength: number;\n  bytesFilled: number;\n  elementSize: number;\n  viewConstructor: ArrayBufferViewConstructor<Uint8Array>;\n  readerType: 'default';\n}\n\ninterface BYOBPullIntoDescriptor<T extends ArrayBufferView = ArrayBufferView> {\n  buffer: ArrayBufferLike;\n  bufferByteLength: number;\n  byteOffset: number;\n  byteLength: number;\n  bytesFilled: number;\n  elementSize: number;\n  viewConstructor: ArrayBufferViewConstructor<T>;\n  readerType: 'byob';\n}\n\n/**\n * Allows control of a {@link ReadableStream | readable byte stream}'s state and internal queue.\n *\n * @public\n */\nexport class ReadableByteStreamController {\n  /** @internal */\n  _controlledReadableByteStream!: ReadableByteStream;\n  /** @internal */\n  _queue!: SimpleQueue<ByteQueueElement>;\n  /** @internal */\n  _queueTotalSize!: number;\n  /** @internal */\n  _started!: boolean;\n  /** @internal */\n  _closeRequested!: boolean;\n  /** @internal */\n  _pullAgain!: boolean;\n  /** @internal */\n  _pulling !: boolean;\n  /** @internal */\n  _strategyHWM!: number;\n  /** @internal */\n  _pullAlgorithm!: () => Promise<void>;\n  /** @internal */\n  _cancelAlgorithm!: (reason: any) => Promise<void>;\n  /** @internal */\n  _autoAllocateChunkSize: number | undefined;\n  /** @internal */\n  _byobRequest: ReadableStreamBYOBRequest | null;\n  /** @internal */\n  _pendingPullIntos!: SimpleQueue<PullIntoDescriptor>;\n\n  private constructor() {\n    throw new TypeError('Illegal constructor');\n  }\n\n  /**\n   * Returns the current BYOB pull request, or `null` if there isn't one.\n   */\n  get byobRequest(): ReadableStreamBYOBRequest | null {\n    if (!IsReadableByteStreamController(this)) {\n      throw byteStreamControllerBrandCheckException('byobRequest');\n    }\n\n    return ReadableByteStreamControllerGetBYOBRequest(this);\n  }\n\n  /**\n   * Returns the desired size to fill the controlled stream's internal queue. It can be negative, if the queue is\n   * over-full. An underlying byte source ought to use this information to determine when and how to apply backpressure.\n   */\n  get desiredSize(): number | null {\n    if (!IsReadableByteStreamController(this)) {\n      throw byteStreamControllerBrandCheckException('desiredSize');\n    }\n\n    return ReadableByteStreamControllerGetDesiredSize(this);\n  }\n\n  /**\n   * Closes the controlled readable stream. Consumers will still be able to read any previously-enqueued chunks from\n   * the stream, but once those are read, the stream will become closed.\n   */\n  close(): void {\n    if (!IsReadableByteStreamController(this)) {\n      throw byteStreamControllerBrandCheckException('close');\n    }\n\n    if (this._closeRequested) {\n      throw new TypeError('The stream has already been closed; do not close it again!');\n    }\n\n    const state = this._controlledReadableByteStream._state;\n    if (state !== 'readable') {\n      throw new TypeError(`The stream (in ${state} state) is not in the readable state and cannot be closed`);\n    }\n\n    ReadableByteStreamControllerClose(this);\n  }\n\n  /**\n   * Enqueues the given chunk chunk in the controlled readable stream.\n   * The chunk has to be an `ArrayBufferView` instance, or else a `TypeError` will be thrown.\n   */\n  enqueue(chunk: ArrayBufferView): void;\n  enqueue(chunk: ArrayBufferView | undefined): void {\n    if (!IsReadableByteStreamController(this)) {\n      throw byteStreamControllerBrandCheckException('enqueue');\n    }\n\n    assertRequiredArgument(chunk, 1, 'enqueue');\n    if (!ArrayBuffer.isView(chunk)) {\n      throw new TypeError('chunk must be an array buffer view');\n    }\n    if (chunk.byteLength === 0) {\n      throw new TypeError('chunk must have non-zero byteLength');\n    }\n    if (chunk.buffer.byteLength === 0) {\n      throw new TypeError(`chunk's buffer must have non-zero byteLength`);\n    }\n\n    if (this._closeRequested) {\n      throw new TypeError('stream is closed or draining');\n    }\n\n    const state = this._controlledReadableByteStream._state;\n    if (state !== 'readable') {\n      throw new TypeError(`The stream (in ${state} state) is not in the readable state and cannot be enqueued to`);\n    }\n\n    ReadableByteStreamControllerEnqueue(this, chunk);\n  }\n\n  /**\n   * Errors the controlled readable stream, making all future interactions with it fail with the given error `e`.\n   */\n  error(e: any = undefined): void {\n    if (!IsReadableByteStreamController(this)) {\n      throw byteStreamControllerBrandCheckException('error');\n    }\n\n    ReadableByteStreamControllerError(this, e);\n  }\n\n  /** @internal */\n  [CancelSteps](reason: any): Promise<void> {\n    ReadableByteStreamControllerClearPendingPullIntos(this);\n\n    ResetQueue(this);\n\n    const result = this._cancelAlgorithm(reason);\n    ReadableByteStreamControllerClearAlgorithms(this);\n    return result;\n  }\n\n  /** @internal */\n  [PullSteps](readRequest: ReadRequest<Uint8Array>): void {\n    const stream = this._controlledReadableByteStream;\n    assert(ReadableStreamHasDefaultReader(stream));\n\n    if (this._queueTotalSize > 0) {\n      assert(ReadableStreamGetNumReadRequests(stream) === 0);\n\n      const entry = this._queue.shift()!;\n      this._queueTotalSize -= entry.byteLength;\n\n      ReadableByteStreamControllerHandleQueueDrain(this);\n\n      const view = new Uint8Array(entry.buffer, entry.byteOffset, entry.byteLength);\n\n      readRequest._chunkSteps(view);\n      return;\n    }\n\n    const autoAllocateChunkSize = this._autoAllocateChunkSize;\n    if (autoAllocateChunkSize !== undefined) {\n      let buffer: ArrayBuffer;\n      try {\n        buffer = new ArrayBuffer(autoAllocateChunkSize);\n      } catch (bufferE) {\n        readRequest._errorSteps(bufferE);\n        return;\n      }\n\n      const pullIntoDescriptor: DefaultPullIntoDescriptor = {\n        buffer,\n