}
        };

    assertThat(FluentIterable.from(iterable).copyInto(list))
        .containsExactly(1, 2, 3, 9, 8, 7)
        .inOrder();
  }

  public void testJoin() {
    assertThat(fluent(2, 1, 3, 4).join(Joiner.on(","))).isEqualTo("2,1,3,4");
  }

  public void testJoin_empty() {
    assertThat(fluent().join(Joiner.on(","))).isEqualTo("");
  }

    assertThrows(IllegalArgumentException.class, () -> Longs.ensureCapacity(ARRAY1, -1, 1));
    assertThrows(IllegalArgumentException.class, () -> Longs.ensureCapacity(ARRAY1, 1, -1));
  }

  public void testJoin() {
    assertThat(Longs.join(",", EMPTY)).isEmpty();
    assertThat(Longs.join(",", ARRAY1)).isEqualTo("1");
    assertThat(Longs.join(",", 1L, 2L)).isEqualTo("1,2");