@Test
public void verifyAggregateDataValuesOnExistingPSI_PayloadHasMoreDataValues()
{

    Event event1 = createEvent(
        createDataValue( "abcd", "val1" ),
        createDataValue( "efgh", "val2" ),
        createDataValue( "ilmn", "val3" ),
        createDataValue( "gggg", "val4" ) );
    Map<String, ProgramStageInstance> programStageInstanceMap = new HashMap<>();
    programStageInstanceMap.put( event1.getUid(),
        createPsi( event1.getUid(),
        createEventDataValue( "abcd", "val1" ),
        createEventDataValue( "efgh", "val2" ),
        createEventDataValue( "ilmn", "val3" ) ) );
    Map<String, Set<EventDataValue>> dataValues = subject.aggregateDataValues( Lists.newArrayList( event1 ),
        programStageInstanceMap, importOptions );
    assertThat( dataValues, is( notNullValue() ) );
    assertThat( dataValues.keySet(), hasSize( 1 ) );
    assertThat( dataValues.get( event1.getUid() ), hasSize( 4 ) );
    assertDataValue( dataValues.get( event1.getUid() ), "abcd", "val1" );
    assertDataValue( dataValues.get( event1.getUid() ), "efgh", "val2" );
    assertDataValue( dataValues.get( event1.getUid() ), "ilmn", "val3" );
    assertDataValue( dataValues.get( event1.getUid() ), "gggg", "val4" );
}