knowledge of phpunit

ArrayTest.php

<?php
class ArrayTest extends PHPUnit_Framework_TestCase {
  	/**
  	 * @test
  	 */
	public function array_test() {
		$actual = ['b', 'a'];
		$expect = ['a', 'b'];
		$this->assertSame($expect, $actual);
		/*
			Failed asserting that Array &0 (
			    0 => 'b'
			    1 => 'a'
			) is identical to Array &0 (
			    0 => 'a'
			    1 => 'b'
			).
		 */
	}
}