public void test_combinedWith_differentTypes() {
Map<MarketDataId<?>, Object> dataMap1 = ImmutableMap.of(ID1, VAL1, ID2, VAL2);
MarketData test1 = MarketData.of(VAL_DATE, dataMap1);
Map<MarketDataId<?>, Object> dataMap2 = ImmutableMap.of(ID1, VAL1);
MarketData test2 = MarketData.of(VAL_DATE, dataMap2);
ExtendedMarketData<String> test3 = ExtendedMarketData.of(ID1, VAL3, test2);
MarketData test = test3.combinedWith(test1);
assertEquals(test.getValue(ID1), VAL3);
assertEquals(test.getValue(ID2), VAL2);
assertEquals(test.getIds(), ImmutableSet.of(ID1, ID2));
}