map.put(FieldNames.TIMESTAMP, timestamp.toInstant().toEpochMilli());
        return map;
    }

    /**
     * Concatenates values to a destination list, avoiding duplicates.
     * @param dest The destination list.
     * @param newValues The new values to add.
     * @param <T> The type of the values.
     */

        assertNotNull(invalidKeywords);
        assertEquals(0, invalidKeywords.size());
    }

    @Test
    public void testGetKeywordsWithDuplicates() {
        // Test that duplicates are removed
        String query = "test test query";
        String[] fields = { "content" };
        List<String> keywords = SuggestUtil.getKeywords(query, fields);
        assertNotNull(keywords);