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diff --git a/cli/js/streams/shared-internals.ts b/cli/js/streams/shared-internals.ts
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+// Forked from https://github.com/stardazed/sd-streams/tree/8928cf04b035fd02fb1340b7eb541c76be37e546
+// Copyright (c) 2018-Present by Arthur Langereis - @zenmumbler MIT
+
+/**
+ * streams/shared-internals - common types and methods for streams
+ * Part of Stardazed
+ * (c) 2018-Present by Arthur Langereis - @zenmumbler
+ * https://github.com/stardazed/sd-streams
+ */
+
+/* eslint-disable @typescript-eslint/no-explicit-any */
+// TODO don't disable this warning
+
+import { AbortSignal, QueuingStrategySizeCallback } from "../dom_types.ts";
+import { DenoError, ErrorKind } from "../errors.ts";
+
+// common stream fields
+
+export const state_ = Symbol("state_");
+export const storedError_ = Symbol("storedError_");
+
+// ---------
+
+/** An error reason / result can be anything */
+export type ErrorResult = any;
+
+// ---------
+
+export function isInteger(value: number): boolean {
+  if (!isFinite(value)) {
+    // covers NaN, +Infinity and -Infinity
+    return false;
+  }
+  const absValue = Math.abs(value);
+  return Math.floor(absValue) === absValue;
+}
+
+export function isFiniteNonNegativeNumber(value: unknown): boolean {
+  if (!(typeof value === "number" && isFinite(value))) {
+    // covers NaN, +Infinity and -Infinity
+    return false;
+  }
+  return value >= 0;
+}
+
+export function isAbortSignal(signal: any): signal is AbortSignal {
+  if (typeof signal !== "object" || signal === null) {
+    return false;
+  }
+  try {
+    // TODO
+    // calling signal.aborted() probably isn't the right way to perform this test
+    // https://github.com/stardazed/sd-streams/blob/master/packages/streams/src/shared-internals.ts#L41
+    signal.aborted();
+    return true;
+  } catch (err) {
+    return false;
+  }
+}
+
+export function invokeOrNoop<O extends object, P extends keyof O>(
+  o: O,
+  p: P,
+  args: any[]
+): any {
+  // Assert: O is not undefined.
+  // Assert: IsPropertyKey(P) is true.
+  // Assert: args is a List.
+  const method: Function | undefined = (o as any)[p]; // tslint:disable-line:ban-types
+  if (method === undefined) {
+    return undefined;
+  }
+  return Function.prototype.apply.call(method, o, args);
+}
+
+export function cloneArrayBuffer(
+  srcBuffer: ArrayBufferLike,
+  srcByteOffset: number,
+  srcLength: number,
+  cloneConstructor: ArrayBufferConstructor | SharedArrayBufferConstructor
+): InstanceType<typeof cloneConstructor> {
+  // this function fudges the return type but SharedArrayBuffer is disabled for a while anyway
+  return srcBuffer.slice(
+    srcByteOffset,
+    srcByteOffset + srcLength
+  ) as InstanceType<typeof cloneConstructor>;
+}
+
+export function transferArrayBuffer(buffer: ArrayBufferLike): ArrayBuffer {
+  // This would in a JS engine context detach the buffer's backing store and return
+  // a new ArrayBuffer with the same backing store, invalidating `buffer`,
+  // i.e. a move operation in C++ parlance.
+  // Sadly ArrayBuffer.transfer is yet to be implemented by a single browser vendor.
+  return buffer.slice(0); // copies instead of moves
+}
+
+export function copyDataBlockBytes(
+  toBlock: ArrayBufferLike,
+  toIndex: number,
+  fromBlock: ArrayBufferLike,
+  fromIndex: number,
+  count: number
+): void {
+  new Uint8Array(toBlock, toIndex, count).set(
+    new Uint8Array(fromBlock, fromIndex, count)
+  );
+}
+
+// helper memoisation map for object values
+// weak so it doesn't keep memoized versions of old objects indefinitely.
+const objectCloneMemo = new WeakMap<object, object>();
+
+let sharedArrayBufferSupported_: boolean | undefined;
+function supportsSharedArrayBuffer(): boolean {
+  if (sharedArrayBufferSupported_ === undefined) {
+    try {
+      new SharedArrayBuffer(16);
+      sharedArrayBufferSupported_ = true;
+    } catch (e) {
+      sharedArrayBufferSupported_ = false;
+    }
+  }
+  return sharedArrayBufferSupported_;
+}
+
+/**
+ * Implement a method of value cloning that is reasonably close to performing `StructuredSerialize(StructuredDeserialize(value))`
+ * from the HTML standard. Used by the internal `readableStreamTee` method to clone values for connected implementations.
+ * @see https://html.spec.whatwg.org/multipage/structured-data.html#structuredserializeinternal
+ */
+export function cloneValue(value: any): any {
+  const valueType = typeof value;
+  switch (valueType) {
+    case "number":
+    case "string":
+    case "boolean":
+    case "undefined":
+    // @ts-ignore
+    case "bigint":
+      return value;
+    case "object": {
+      if (objectCloneMemo.has(value)) {
+        return objectCloneMemo.get(value);
+      }
+      if (value === null) {
+        return value;
+      }
+      if (value instanceof Date) {
+        return new Date(value.valueOf());
+      }
+      if (value instanceof RegExp) {
+        return new RegExp(value);
+      }
+      if (supportsSharedArrayBuffer() && value instanceof SharedArrayBuffer) {
+        return value;
+      }
+      if (value instanceof ArrayBuffer) {
+        const cloned = cloneArrayBuffer(
+          value,
+          0,
+          value.byteLength,
+          ArrayBuffer
+        );
+        objectCloneMemo.set(value, cloned);
+        return cloned;
+      }
+      if (ArrayBuffer.isView(value)) {
+        const clonedBuffer = cloneValue(value.buffer) as ArrayBufferLike;
+        // Use DataViewConstructor type purely for type-checking, can be a DataView or TypedArray.
+        // They use the same constructor signature, only DataView has a length in bytes and TypedArrays
+        // use a length in terms of elements, so we adjust for that.
+        let length: number;
+        if (value instanceof DataView) {
+          length = value.byteLength;
+        } else {
+          length = (value as Uint8Array).length;
+        }
+        return new (value.constructor as DataViewConstructor)(
+          clonedBuffer,
+          value.byteOffset,
+          length
+        );
+      }
+      if (value instanceof Map) {
+        const clonedMap = new Map();
+        objectCloneMemo.set(value, clonedMap);
+        value.forEach((v, k) => clonedMap.set(k, cloneValue(v)));
+        return clonedMap;
+      }
+      if (value instanceof Set) {
+        const clonedSet = new Map();
+        objectCloneMemo.set(value, clonedSet);
+        value.forEach((v, k) => clonedSet.set(k, cloneValue(v)));
+        return clonedSet;
+      }
+
+      // generic object
+      const clonedObj = {} as any;
+      objectCloneMemo.set(value, clonedObj);
+      const sourceKeys = Object.getOwnPropertyNames(value);
+      for (const key of sourceKeys) {
+        clonedObj[key] = cloneValue(value[key]);
+      }
+      return clonedObj;
+    }
+    case "symbol":
+    case "function":
+    default:
+      // TODO this should be a DOMException,
+      // https://github.com/stardazed/sd-streams/blob/master/packages/streams/src/shared-internals.ts#L171
+      throw new DenoError(
+        ErrorKind.DataCloneError,
+        "Uncloneable value in stream"
+      );
+  }
+}
+
+export function promiseCall<F extends Function>(
+  f: F,
+  v: object | undefined,
+  args: any[]
+): Promise<any> {
+  // tslint:disable-line:ban-types
+  try {
+    const result = Function.prototype.apply.call(f, v, args);
+    return Promise.resolve(result);
+  } catch (err) {
+    return Promise.reject(err);
+  }
+}
+
+export function createAlgorithmFromUnderlyingMethod<
+  O extends object,
+  K extends keyof O
+>(obj: O, methodName: K, extraArgs: any[]): any {
+  const method = obj[methodName];
+  if (method === undefined) {
+    return (): any => Promise.resolve(undefined);
+  }
+  if (typeof method !== "function") {
+    throw new TypeError(`Field "${methodName}" is not a function.`);
+  }
+  return function(...fnArgs: any[]): any {
+    return promiseCall(method, obj, fnArgs.concat(extraArgs));
+  };
+}
+
+/*
+Deprecated for now, all usages replaced by readableStreamCreateReadResult
+
+function createIterResultObject<T>(value: T, done: boolean): IteratorResult<T> {
+	return { value, done };
+}
+*/
+
+export function validateAndNormalizeHighWaterMark(hwm: unknown): number {
+  const highWaterMark = Number(hwm);
+  if (isNaN(highWaterMark) || highWaterMark < 0) {
+    throw new RangeError(
+      "highWaterMark must be a valid, non-negative integer."
+    );
+  }
+  return highWaterMark;
+}
+
+export function makeSizeAlgorithmFromSizeFunction<T>(
+  sizeFn: undefined | ((chunk: T) => number)
+): QueuingStrategySizeCallback<T> {
+  if (typeof sizeFn !== "function" && typeof sizeFn !== "undefined") {
+    throw new TypeError("size function must be undefined or a function");
+  }
+  return function(chunk: T): number {
+    if (typeof sizeFn === "function") {
+      return sizeFn(chunk);
+    }
+    return 1;
+  };
+}
+
+// ----
+
+export const enum ControlledPromiseState {
+  Pending,
+  Resolved,
+  Rejected
+}
+
+export interface ControlledPromise<V> {
+  resolve(value?: V): void;
+  reject(error: ErrorResult): void;
+  promise: Promise<V>;
+  state: ControlledPromiseState;
+}
+
+export function createControlledPromise<V>(): ControlledPromise<V> {
+  const conProm = {
+    state: ControlledPromiseState.Pending
+  } as ControlledPromise<V>;
+  conProm.promise = new Promise<V>(function(resolve, reject) {
+    conProm.resolve = function(v?: V): void {
+      conProm.state = ControlledPromiseState.Resolved;
+      resolve(v);
+    };
+    conProm.reject = function(e?: ErrorResult): void {
+      conProm.state = ControlledPromiseState.Rejected;
+      reject(e);
+    };
+  });
+  return conProm;
+}