sendou.ink/app/utils/arrays.test.ts

import { describe, expect, it } from "vitest";
import { diff } from "./arrays";

describe("diff", () => {
	it("should return elements in arr2 but not in arr1", () => {
		const arr1 = [1, 2, 3];
		const arr2 = [2, 3, 4, 4];
		const result = diff(arr1, arr2);
		expect(result).toEqual([4, 4]);
	});

	it("should return an empty array if arr2 is empty", () => {
		const arr1 = [1, 2, 3];
		const arr2: number[] = [];
		const result = diff(arr1, arr2);
		expect(result).toEqual([]);
	});

	it("should return all elements of arr2 if arr1 is empty", () => {
		const arr1: number[] = [];
		const arr2 = [1, 2, 3];
		const result = diff(arr1, arr2);
		expect(result).toEqual([1, 2, 3]);
	});

	it("should handle arrays with duplicate elements", () => {
		const arr1 = [1, 2, 2, 3];
		const arr2 = [2, 2, 3, 3, 4];
		const result = diff(arr1, arr2);
		expect(result).toEqual([3, 4]);
	});

	it("should return an empty array if both arrays are the same", () => {
		const arr1 = [1, 2, 3];
		const arr2 = [1, 2, 3];
		const result = diff(arr1, arr2);
		expect(result).toEqual([]);
	});
});