// RRF should merge duplicates and boost their scores
        }
    }

    /**
     * Test that close can be called multiple times safely.
     */
    @Test
    public void test_multipleCloseCallsSafe() throws Exception {
        RankFusionProcessor processor = new RankFusionProcessor();
        processor.setSearcher(new TestSearcher(100));
        processor.init();

        // First close