java - 将 Junit 中的 Argument Captor 的选择性字段与 Mockito 进行比较

Question

我正在使用 Spock 和 Mockito 框架编写单元测试，并且偶然发现了 Mockito 中的一个我无法优雅解决的限制。

以下代码解析 .csv 文件并返回 TradedInstrument 对象的集合:

@ManagedOperation
public Collection<TradedInstrument> loadTradedInstrumentFromBatchFile() {
    Collection<TradedInstrument> tradedInstrumentsFrombatchFile = new ArrayList<>();
    try (BufferedReader br = new BufferedReader(new InputStreamReader(
                this.getClass().getResourceAsStream("/" + tradedInstrumentBatchFilename)))) {
        String line;
        while ((line = br.readLine()) != null) {
            String[] instrumentAttributes = line.split(",");
            TradedInstrument tradedInstrument = new TradedInstrument();
            tradedInstrument.setInstId(instrumentAttributes[0]);
            tradedInstrument.setPriceSource(PriceSource.valueOf(instrumentAttributes[1]));
            tradedInstrument.setPrice(new BigDecimal(instrumentAttributes[2]));
            tradedInstrument.setDateCreated(businessDateDao.getBusinessDate());

            insertTradedInstrument(tradedInstrument);
            tradedInstrumentsFrombatchFile.add(tradedInstrument);
            LOGGER.info("Loaded traded instrument: " + tradedInstrument + " from batch file: " + tradedInstrumentBatchFilename);
        }

    } catch (NullPointerException e) {
        String errorMessage = "An ERROR occurred locating the traded instrument upload batch file: " + tradedInstrumentBatchFilename;
        LOGGER.error(errorMessage);
        throw new PriceServiceException(errorMessage, e);
    } catch (IOException e) {
        String errorMessage = "An ERROR occurred reading the traded instrument upload batch file: " + tradedInstrumentBatchFilename;
        LOGGER.error(errorMessage);
        throw new PriceServiceException(errorMessage, e);
    } catch (Exception e) {
        String errorMessage = "An ERROR occurred creating traded instrument using data from upload batch file: " + tradedInstrumentBatchFilename;
        LOGGER.error(errorMessage, e);
        throw new PriceServiceException(errorMessage, e);
    }
    return tradedInstrumentsFrombatchFile;
}

我有一个名为“tradedInstrumentBatchFile.csv”的批处理文件，其中包含以下内容:

1234,ICAP,0.4956 2345,BBG,0.8456 8456,NASDAQ,0.3567 5967,REUTERS,0.8675

我用 Groovy 编写了以下 Spock 测试:

def "should load traded instrument from batch file"() {
    given:
    TradedInstrumentSubscriber tradedInstrumentSubscriber = Mock()
    TradedInstrumentTable tradedInstrumentDao = Mock()
    VendorTopicDao vendorTopicDao = Mock()
    TradedInstrumentListener listener = Mock()
    BusinessDateDao businessDateDao = Mock()

    PriceService priceService = new PriceService(tradedInstrumentSubscriber, listener, vendorTopicDao, tradedInstrumentDao, businessDateDao)
    priceService.setTradedInstrumentBatchFilename("tradedInstrumentBatchFile.csv")
    businessDateDao.getBusinessDate() >> new Date()

    when:
    priceService.loadTradedInstrumentFromBatchFile()

    then:
    1 * tradedInstrumentDao.insert(_ as TradedInstrument) >> { TradedInstrument arg ->
        assert arg.instId == "1234"
        assert arg.priceSource == PriceSource.ICAP
        assert arg.price == BigDecimal.valueOf(0.4956)
    }

    1 * tradedInstrumentDao.insert(_ as TradedInstrument) >> { TradedInstrument arg ->
        assert arg.instId == "2345"
        assert arg.priceSource == PriceSource.BBG
        assert arg.price == BigDecimal.valueOf(0.8456)
    }

    1 * tradedInstrumentDao.insert(_ as TradedInstrument) >> { TradedInstrument arg ->
        assert arg.instId == "8456"
        assert arg.priceSource == PriceSource.NASDAQ
        assert arg.price == BigDecimal.valueOf(0.3567)
    }

    1 * tradedInstrumentDao.insert(_ as TradedInstrument) >> { TradedInstrument arg ->
        assert arg.instId == "5967"
        assert arg.priceSource == PriceSource.REUTERS
        assert arg.price == BigDecimal.valueOf(0.8675)
    }
}

我已经使用 Mockito 尝试编写了等效的 Junit 测试:

 @Test
public void shouldLoadTradedInstrumentFromBatchFile() {
    // Given
    VendorTopicDao vendorTopicDao = mock(VendorTopicDao.class);
    TradedInstrumentSubscriber tradedInstrumentSubscriber = mock(TradedInstrumentSubscriber.class);
    TradedInstrumentTable tradedInstrumentDao = mock(TradedInstrumentTable.class);
    TradedInstrumentListener listener = mock(TradedInstrumentListener.class);
    BusinessDateDao businessDateDao = mock(BusinessDateDao.class);
    PriceService priceService = new PriceService(tradedInstrumentSubscriber, listener, vendorTopicDao, tradedInstrumentDao);
    priceService.setTradedInstrumentBatchFilename("tradedInstrumentBatchFile.csv");

    ArgumentCaptor<TradedInstrument> captor = ArgumentCaptor.forClass(TradedInstrument.class);

    when(businessDateDao.getBusinessDate()).thenReturn(new Date());

    // When
    priceService.loadTradedInstrumentFromBatchFile();

    // Then
    verify(tradedInstrumentDao, times(4)).insert(captor.capture());
    List<TradedInstrument> tradedInstruments = captor.getAllValues();

    TradedInstrument tradedInstrument1 = new TradedInstrument();
    tradedInstrument1.setInstId("1234");
    tradedInstrument1.setPriceSource(PriceSource.ICAP);
    tradedInstrument1.setPrice(BigDecimal.valueOf(0.4956));

    TradedInstrument tradedInstrument2 = new TradedInstrument();
    tradedInstrument2.setInstId("2345");
    tradedInstrument2.setPriceSource(PriceSource.BBG);
    tradedInstrument2.setPrice(BigDecimal.valueOf(0.8456));

    TradedInstrument tradedInstrument3= new TradedInstrument();
    tradedInstrument2.setInstId("8456");
    tradedInstrument2.setPriceSource(PriceSource.NASDAQ);
    tradedInstrument2.setPrice(BigDecimal.valueOf(0.3567));

    TradedInstrument tradedInstrument4= new TradedInstrument();
    tradedInstrument2.setInstId("5967");
    tradedInstrument2.setPriceSource(PriceSource.REUTERS);
    tradedInstrument2.setPrice(BigDecimal.valueOf(0.8675));

    assertThat(tradedInstruments, hasItem(tradedInstrument1));
    assertThat(tradedInstruments, hasItem(tradedInstrument2));
    assertThat(tradedInstruments, hasItem(tradedInstrument3));
    assertThat(tradedInstruments, hasItem(tradedInstrument4));
}

Junit 测试失败，因为该测试在比较中包含“dateCreated”字段，而 Spock 测试有选择地忽略该字段。

“dateCreated”字段应该是创建 TradedInstrument 的实际时间，因此有意将其从比较中排除。

我能看到的唯一解决方案是在businessDateDao上添加以下交互:

when(businessDateDao.getBusinessDate()).thenReturn(null);

是否有在 Junit/Mockito 中使用 Matcher 的等效方法来选择性地省略字段的比较？

Answer 1

您可以结合使用 hasItem 和 hasProperty 将断言集中在 TradedInstrument 的属性上，这些属性> 人口稠密。例如:

assertThat(tradedInstruments, hasItem(hasProperty("instId", is(1234))));
assertThat(tradedInstruments, hasItem(hasProperty("priceSource", is(PriceSource.ICAP))));
assertThat(tradedInstruments, hasItem(hasProperty("price", is(BigDecimal.valueOf(0.4956)))));

或者你可以声明一个自定义匹配器...

private Matcher<TradedInstrument> isEquivalent(final String instId, final PriceSource priceSource, final BigDecimal price) {
    return new BaseMatcher<TradedInstrument>() {
        @Override
        public boolean matches(final Object item) {
            final TradedInstrument tradedInstrument = (TradedInstrument) item;
            // your custom equality implementation e.g.
            return instId.equals(tradeInstrument.getInstId()) && priceSource == tradeInstrument.getPriceSource() && price.equals(tradeInstrument.getPrice());
        }
        @Override
        public void describeTo(final Description description) {
            description.appendText(String.format("the given object should contain id=%s, priceSource=%s, price=%s ", id, priceSource, price));
        }
    };
}

...并像这样使用它:

assertThat(tradedInstruments, hasItem(isEquivalent(1, PriceSource.ICAP, BigDecimal.valueOf(0.4956))));