while ((read = reader.read(buf)) != -1) {
      writer.write(buf, 0, read);
    }
    reader.close();
    writer.close();

    assertExpectedString(writer.toString());
  }

  public void testCopyTo_appendable() throws IOException {
    StringBuilder builder = new StringBuilder();

    assertEquals(expected.length(), source.copyTo(builder));

    assertExpectedString(builder.toString());
  }

      lines = linesStream.collect(toImmutableList());
    }

    assertTrue(source.wasStreamClosed());
    assertEquals(SPLIT_LINES, lines);
  }

  public void testCopyTo_appendable() throws IOException {
    StringBuilder builder = new StringBuilder();

    assertEquals(STRING.length(), source.copyTo(builder));
    assertTrue(source.wasStreamOpened() && source.wasStreamClosed());

      lines = linesStream.collect(toImmutableList());
    }

    assertTrue(source.wasStreamClosed());
    assertEquals(SPLIT_LINES, lines);
  }

  public void testCopyTo_appendable() throws IOException {
    StringBuilder builder = new StringBuilder();

    assertEquals(STRING.length(), source.copyTo(builder));
    assertTrue(source.wasStreamOpened() && source.wasStreamClosed());