// Forked from https://github.com/stardazed/sd-streams/tree/8928cf04b035fd02fb1340b7eb541c76be37e546 // Copyright (c) 2018-Present by Arthur Langereis - @zenmumbler MIT /* eslint-disable @typescript-eslint/no-explicit-any */ // TODO don't disable this warning import { QueuingStrategySizeCallback } from "../dom_types.d.ts"; // common stream fields export const state_ = Symbol("state_"); export const storedError_ = Symbol("storedError_"); 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: 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 { // this function fudges the return type but SharedArrayBuffer is disabled for a while anyway return srcBuffer.slice( srcByteOffset, srcByteOffset + srcLength ) as InstanceType; } 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(); let sharedArrayBufferSupported_: boolean | undefined; function supportsSharedArrayBuffer(): boolean { if (sharedArrayBufferSupported_ === undefined) { try { new SharedArrayBuffer(16); sharedArrayBufferSupported_ = true; } catch (e) { sharedArrayBufferSupported_ = false; } } return sharedArrayBufferSupported_; } 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 Error("Uncloneable value in stream"); } } export function promiseCall( f: F, v: object | undefined, args: any[] ): Promise { // 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(value: T, done: boolean): IteratorResult { 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( sizeFn: undefined | ((chunk: T) => number) ): QueuingStrategySizeCallback { 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 { resolve(value?: V): void; reject(error: ErrorResult): void; promise: Promise; state: ControlledPromiseState; } export function createControlledPromise(): ControlledPromise { const conProm = { state: ControlledPromiseState.Pending, } as ControlledPromise; conProm.promise = new Promise(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; }