assertTrue(result.contains("NOT exclude"));
        assertTrue(result.contains("filetype:\"pdf\""));
        assertTrue(result.contains("site:example.com"));
    }

    public void test_builderChaining() {
        QueryStringBuilder builder = new QueryStringBuilder();
        assertSame(builder, builder.params(createSimpleParams("test")));
        assertSame(builder, builder.sortField("score"));