assertTrue(sink.wasStreamOpened() && sink.wasStreamClosed());
    assertEquals(STRING, sink.getString());
  }

  public void testWriteFromStream_doesNotCloseThatStream() throws IOException {
    TestReader in = new TestReader();
    assertFalse(in.closed());
    sink.writeFrom(in);
    assertFalse(in.closed());
  }

  public void testWriteLines_withSpecificSeparator() throws IOException {