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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.import { equals } from "./equals.ts";import { assert, assertEquals, assertNotEquals } from "../assert/mod.ts";
Deno.test("equals()", () => {  const v = equals(new Uint8Array([0, 1, 2, 3]), new Uint8Array([0, 1, 2, 3]));  const v2 = equals(new Uint8Array([0, 1, 2, 2]), new Uint8Array([0, 1, 2, 3]));  const v3 = equals(new Uint8Array([0, 1, 2, 3]), new Uint8Array([0, 1, 2]));  assert(v);  assert(!v2);  assert(!v3);});
const THRESHOLD_32_BIT = 160;
Deno.test("equals() handles randomized testing", () => {  // run tests before and after cutoff  for (let len = THRESHOLD_32_BIT - 10; len <= THRESHOLD_32_BIT + 10; len++) {    const arr1 = crypto.getRandomValues(new Uint8Array(len));    const arr2 = crypto.getRandomValues(new Uint8Array(len));    const arr3 = arr1.slice(0);    // the chance of arr1 equaling arr2 is basically 0    // but introduce an inequality at the end just in case    arr2[arr2.length - 1] = arr1.at(-1)! ^ 1;    // arr3 is arr1 but with an inequality in the very last element    // this is to test the equality check when length isn't a multiple of 4    arr3[arr3.length - 1] ^= 1;    // arrays with same underlying ArrayBuffer should be equal    assert(equals(arr1, arr1));    // equal arrays with different underlying ArrayBuffers should be equal    assert(equals(arr1, arr1.slice(0)));    // inequal arrays should be inequal    assert(!equals(arr1, arr2));    assert(!equals(arr1, arr3));  }});
// https://github.com/denoland/deno_std/issues/3603Deno.test("equals() works with .subarray()", () => {  const a = new Uint8Array(1001).subarray(1);  const b = new Uint8Array(1000);  a[0] = 123;  b[0] = 123;  assertEquals(a, b);  assert(equals(a, b));
  const c = new Uint8Array(1001).subarray(1);  const d = new Uint8Array(1000);  c[999] = 123;  assertNotEquals(c, d); // ok  assert(!equals(c, d));
  // Test every length/offset combination (modulo 4) to ensure that every byte is checked.  for (let offsetA = 0; offsetA < 4; offsetA++) {    for (let offsetB = 0; offsetB < 4; offsetB++) {      for (let len = THRESHOLD_32_BIT; len < THRESHOLD_32_BIT + 4; len++) {        const x = new Uint8Array(new ArrayBuffer(len + offsetA), offsetA);        const y = new Uint8Array(new ArrayBuffer(len + offsetB), offsetB);        for (let i = 0; i < len; i++) {          assert(equals(x, y));          x[i] = 1;          assert(!equals(x, y));          y[i] = 1;        }      }    }  }});