public function testShouldNotAllowDuplicateLayers() { $this->testShouldAllowAddingLayers(); $this->helper->addLayer('/js/foo/foo.xd.js'); $layers = $this->helper->getLayers(); $this->assertEquals(2, count($layers)); $this->assertEquals('/js/foo/foo.xd.js', $layers[0]); $this->assertEquals('/js/bar/bar.xd.js', $layers[1]); }