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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
import { assertEquals } from "../testing/asserts.ts";import { intersect } from "./intersect.ts";
function intersectTest<I>(  input: Array<Array<I>>,  expected: Array<I>,  message?: string,) {  const actual = intersect(...input);  assertEquals(actual, expected, message);}
Deno.test({  name: "[collections/intersect] no mutation",  fn() {    const arrayA = [1, 2, 3];    const arrayB = [3, 4, 5];    intersect(arrayA, arrayB);
    assertEquals(arrayA, [1, 2, 3]);    assertEquals(arrayB, [3, 4, 5]);  },});
Deno.test({  name: "[collections/intersect] empty input",  fn() {    intersectTest([], []);  },});
Deno.test({  name: "[collections/intersect] empty arrays",  fn() {    intersectTest([[], []], []);  },});
Deno.test({  name: "[collections/intersect] one side empty",  fn() {    intersectTest([[], ["a", "b", "c"]], []);    intersectTest([["a", "b", "c"], []], []);  },});
Deno.test({  name: "[collections/intersect] empty result",  fn() {    intersectTest([["a", "b", "c"], ["d", "e", "f"]], []);  },});
Deno.test({  name: "[collections/intersect] one or more items in intersection",  fn() {    intersectTest([["a", "b"], ["b", "c"]], ["b"]);    intersectTest([["a", "b", "c", "d"], ["c", "d", "e", "f"]], ["c", "d"]);  },});
Deno.test({  name: "[collections/intersect] duplicates",  fn() {    intersectTest([["a", "b", "c", "b"], ["b", "c"]], ["b", "c"]);    intersectTest([["a", "b"], ["b", "b", "c", "c"]], ["b"]);  },});
Deno.test({  name: "[collections/intersect] more than two inputs",  fn() {    intersectTest(      [        ["a", "b"],        ["b", "c"],        ["s", "b"],        ["b", "b"],      ],      ["b"],    );    intersectTest(      [        [1],        [1],        [2],      ],      [],    );    intersectTest(      [        [true, false],        [true, false],        [true],      ],      [true],    );  },});
Deno.test({  name: "[collections/intersect] objects",  fn() {    intersectTest<Record<string, string>>([      [{ foo: "bar" }, { bar: "baz" }],      [{ fruit: "banana" }],    ], []);
    const obj = { bar: "baz" };    intersectTest<Record<string, string>>([      [{ foo: "bar" }, obj],      [obj],    ], [obj]);    intersectTest<Record<string, string>>([      [{ foo: "bar" }, { bar: "baz" }],      [{ bar: "banana" }],    ], []);  },});
Deno.test({  name: "[collections/intersect] functions",  fn() {    intersectTest([      [() => {}, () => null],      [() => NaN],    ], []);
    const emptyObjectFunction = () => {};    intersectTest([      [emptyObjectFunction, () => null],      [emptyObjectFunction],    ], [emptyObjectFunction]);    intersectTest([      [(a: number, b: number) => a + b, () => null],      [(a: number, b: number) => a - b],    ], []);  },});