mergedItem.setKinds(mergeKinds(item1.getKinds(), item2.getKinds()));

        // Take newer values from item2
        mergedItem.setTimestamp(item2.getTimestamp());
        mergedItem.setUserBoost(item2.getUserBoost());
        mergedItem.setEmptySource(item2.toEmptyMap());

        // Sum frequencies
        mergedItem.setQueryFreq(item1.getQueryFreq() + item2.getQueryFreq());

        assertNotNull(item);
        assertEquals("test text", item.getText());
        assertEquals(10L, item.getDocFreq());
        assertEquals(5L, item.getQueryFreq());
        assertEquals(1.5f, item.getUserBoost(), 0.001f);
    }

    @Test
    public void testToJson() {
        String[] text = { "json test" };
        String[][] readings = { { "reading" } };
        String[] fields = { "field" };

        assertNotNull(merged);
        assertEquals(30L, merged.getDocFreq()); // 10 + 20
        assertEquals(20L, merged.getQueryFreq()); // 5 + 15
        assertEquals(2.0f, merged.getUserBoost(), 0.001f); // max(1.0, 2.0)
    }

    @Test
    public void testMerge_tags() {
        SuggestItem item1 = createItemWithTags("text", "tag1", "tag2");