@Test
public void growTest() {

    char[] letters =
            array( 'a', 'b', 'c', 'd', 'e' );
    letters = grow( letters, 21 );
    assertEquals(
            'e',
            idx( letters, 4 )
    );
    assertEquals(
            'a',
            idx( letters, 0 )
    );
    assertEquals(
            len( letters ),
            26
    );
    assertEquals(
            '\0',
            idx( letters, 20 )
    );
    letters = shrink( letters, 23 );
    assertArrayEquals(
            array( 'a', 'b', 'c' ),
            letters
    );
}