def test_containsExtension(self): d = Directory("dir") f1 = File("dir/text.txt") f2 = File("dir/image.png") d.createDir() f1.createFile() f2.createFile() self.assertTrue(d.containsFileExtension(".txt"), "Directory contains .txt") self.assertTrue(d.containsFileExtension(".png"), "Directory contains .png") self.assertFalse(d.containsFileExtension(".pdf"), "Directory does not contain .pdf") d.removeDir()