Iterator<String> iterator = asList(sourceArray).iterator();
    String[] newArray = Iterators.toArray(iterator, String.class);
    assertThat(newArray).isEqualTo(sourceArray);
  }

  public void testFilterSimple() {
    Iterator<String> unfiltered = Lists.newArrayList("foo", "bar").iterator();
    Iterator<String> filtered = filter(unfiltered, equalTo("foo"));
    List<String> expected = singletonList("foo");