(CUT)这是我测试的(Java)类：

public final class NutritionalConsultant {
    public static boolean isLunchTime() {
        int hour = LocalDateTime.now().getHour();
        return hour >= 12 && hour <= 14;
    }
}

(j.1)这是一个有效的Java测试类

@RunWith(JMockit.class)
public class NutritionalConsultantTest {
    @Test
    public void shouldReturnTrueFor12h(@Mocked final LocalDateTime dateTime) {
        new Expectations() {{
            LocalDateTime.now(); result = dateTime;
            dateTime.getHour(); result = 12;
        }};
        boolean isLunchTime = NutritionalConsultant.isLunchTime();
        assertThat(isLunchTime,is(true));
    }
}

(kt.1)但是,相应的kotlin类会引发异常

RunWith(javaClass<JMockit>())
public class NutritionalConsultantKt1Test {
 
    Test
    public fun shouldReturnTrueFor12h(Mocked dateTime : LocalDateTime) {
        object : Expectations() {{
            LocalDateTime.now(); result = dateTime;
            dateTime.getHour(); result = 12;
        }}
        val isLunchTime = NutritionalConsultant.isLunchTime()
        assertThat(isLunchTime,eq(true));
    }
}

例外：

java.lang.Exception: Method shouldReturnTrueFor12h should have no parameters
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:41)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:212)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)

使用gradle运行时会抛出相同的异常.

(kt.2)在kotlin中使用@Mocked语法我得到了一个不同的异常：

RunWith(javaClass<JMockit>())
public class NutritionalConsultantKt2Test {
    Mocked
    var dateTime : LocalDateTime by Delegates.notNull()
 
    Test
    public fun shouldReturnTrueFor12h() {
        object : Expectations() {{
            LocalDateTime.now(); result = dateTime;
            dateTime.getHour(); result = 12;
        }}
        val isLunchTime = NutritionalConsultant.isLunchTime()
        assertThat(isLunchTime,eq(true));
    }
}

例外：

java.lang.IllegalArgumentException: Final mock field "dateTime$delegate" must be of a class type
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:74)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:212)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)

编辑20150224这可能与“对于模拟字段有关,声明类型的实例将由JMockit自动创建并分配给字段,前提是它不是最终的.” (自http://jmockit.org/tutorial/BehaviorBasedTesting.html起)

(kt.3)然而,将val更改为var并使用!!运算符导致工作测试…但这不是惯用的kotlin代码：

RunWith(javaClass<JMockit>())
public class NutritionalConsultantKt3Test {
    Mocked
    var dateTime : LocalDateTime? = null
 
    Test
    public fun shouldReturnTrueFor12h() {
        object : Expectations() {{
            LocalDateTime.now(); result = dateTime;
            dateTime!!.getHour(); result = 12;
        }}
        val isLunchTime = NutritionalConsultant.isLunchTime()
        assertThat(isLunchTime,eq(true));
    }
}

使用kotlin和jmockit有没有更多的成功？