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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
import { assertEquals } from "../assert/mod.ts";import { permutations } from "./permutations.ts";
function permutationsTest<T>(  input: [Array<T>],  expected: Array<Array<T>>,  message?: string,) {  const actual = permutations(...input);  assertEquals(actual, expected, message);}
Deno.test({  name: "permutations() handles no mutation",  fn() {    const array = [1, 2, 3];    permutations(array);
    assertEquals(array, [1, 2, 3]);  },});
Deno.test({  name: "permutations() handles empty input",  fn() {    permutationsTest(      [[]],      [],    );  },});
Deno.test({  name: "permutations() handles one element",  fn() {    permutationsTest(      [        [true],      ],      [[true]],    );    permutationsTest(      [        [undefined],      ],      [[undefined]],    );  },});
Deno.test({  name: "permutations() ignores equality",  fn() {    permutationsTest(      [[1, 1]],      [[1, 1], [1, 1]],    );  },});
Deno.test({  name: "permutations() handles examples",  fn() {    permutationsTest(      [["a", "b", "c"]],      [        ["a", "b", "c"],        ["b", "a", "c"],        ["c", "a", "b"],        ["a", "c", "b"],        ["b", "c", "a"],        ["c", "b", "a"],      ],    );    permutationsTest(      [[true, false, true]],      [        [true, false, true],        [false, true, true],        [true, true, false],        [true, true, false],        [false, true, true],        [true, false, true],      ],    );  },});