private $stack; protected function setUp() { $this-‐>stack = new Stack; } public function testInitialStackIsEmpty() { $this-‐>assertEquals(0, count($this-‐>stack-‐>getItems())); } public function testPushedItemIsInTheStack() { $this-‐>stack-‐>push(5); $this-‐>assertContains(5, $this-‐>stack-‐>getItems()); } }