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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.import { delay } from "./delay.ts";import { ERROR_WHILE_MAPPING_MESSAGE, pooledMap } from "./pool.ts";import {  assert,  assertEquals,  assertRejects,  assertStringIncludes,} from "../assert/mod.ts";
Deno.test("pooledMap()", async () => {  const start = new Date();  const results = pooledMap(    2,    [1, 2, 3],    (i) => new Promise<number>((r) => setTimeout(() => r(i), 1000)),  );  const array = await Array.fromAsync(results);  assertEquals(array, [1, 2, 3]);  const diff = new Date().getTime() - start.getTime();  assert(diff >= 2000);  assert(diff < 3000);});
Deno.test("pooledMap() handles errors", async () => {  async function mapNumber(n: number): Promise<number> {    if (n <= 2) {      throw new Error(`Bad number: ${n}`);    }    await delay(100);    return n;  }  const mappedNumbers: number[] = [];  const error = await assertRejects(    async () => {      for await (const m of pooledMap(3, [1, 2, 3, 4], mapNumber)) {        mappedNumbers.push(m);      }    },    AggregateError,    ERROR_WHILE_MAPPING_MESSAGE,  );  assertEquals(error.errors.length, 2);  assertStringIncludes(error.errors[0].stack, "Error: Bad number: 1");  assertStringIncludes(error.errors[1].stack, "Error: Bad number: 2");  assertEquals(mappedNumbers, [3]);});
Deno.test("pooledMap() returns ordered items", async () => {  function getRandomInt(min: number, max: number): number {    min = Math.ceil(min);    max = Math.floor(max);    return Math.floor(Math.random() * (max - min) + min); //The maximum is exclusive and the minimum is inclusive  }
  const results = pooledMap(    2,    [1, 2, 3, 4, 5, 6, 7, 8, 9, 10],    (i) =>      new Promise<number>((r) =>        setTimeout(() => r(i), getRandomInt(5, 20) * 100)      ),  );
  const returned = await Array.fromAsync(results);  assertEquals(returned, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);});
Deno.test("pooledMap() checks browser compat", async () => {  // Simulates the environment where Symbol.asyncIterator is not available  const asyncIterFunc = ReadableStream.prototype[Symbol.asyncIterator];  // deno-lint-ignore no-explicit-any  delete (ReadableStream.prototype as any)[Symbol.asyncIterator];  try {    const results = pooledMap(      2,      [1, 2, 3],      (i) => new Promise<number>((r) => setTimeout(() => r(i), 100)),    );    const array = await Array.fromAsync(results);    assertEquals(array, [1, 2, 3]);  } finally {    ReadableStream.prototype[Symbol.asyncIterator] = asyncIterFunc;  }});