@Test
public void getAttribute() {

    String attributeValue = "openssh-client";
    List<String> expectedValues = new ArrayList<>(Arrays.asList(attributeValue));
    cookbookConfiguration.putAttribute("[openssh][package_name]", Collections.singletonList(attributeValue));
    assertEquals(expectedValues, cookbookConfiguration.getAttribute("[openssh][package_name]"));
    assertNull(cookbookConfiguration.getAttribute("thiskeydoesnoetexist"));
}