JUnit 5更新(以及我的观点)

我认为这对JUnit来说是非常重要的功能，如果JUnit的作者不想要订单功能，为什么?

默认情况下，单元测试库不会尝试按照源文件中出现的顺序执行测试。

JUnit 5和JUnit 4一样以这种方式工作。为什么?因为如果顺序很重要，这意味着一些测试在它们之间是耦合的，这对于单元测试来说是不可取的。 所以JUnit 5引入的@Nested特性遵循相同的默认方法。

But for integration tests, the order of the test method may matter since a test method may change the state of the application in a way expected by another test method. For example when you write an integration test for a e-shop checkout processing, the first test method to be executed is registering a client, the second is adding items in the basket and the last one is doing the checkout. If the test runner doesn't respect that order, the test scenario is flawed and will fail. So in JUnit 5 (from the 5.4 version) you have all the same the possibility to set the execution order by annotating the test class with @TestMethodOrder(OrderAnnotation.class) and by specifying the order with @Order(numericOrderValue) for the methods which the order matters.

例如:

@TestMethodOrder(OrderAnnotation.class) 
class FooTest {

    @Order(3)
    @Test
    void checkoutOrder() {
        System.out.println("checkoutOrder");
    }

    @Order(2)
    @Test
    void addItemsInBasket() {
        System.out.println("addItemsInBasket");
    }

    @Order(1)
    @Test
    void createUserAndLogin() {
        System.out.println("createUserAndLogin");
    }
}

输出:

创建用户和登录 添加物品在购物篮 结帐订单

顺便说一下，指定@TestMethodOrder(OrderAnnotation.class)看起来不需要(至少在我测试的5.4.0版本中是这样)。

边注 关于这个问题:JUnit 5是编写集成测试的最佳选择吗?我不认为它应该是首先考虑的工具(Cucumber和co可能经常为集成测试带来更具体的价值和特性)，但在一些集成测试用例中，JUnit框架就足够了。所以这个功能的存在是个好消息。

JUnit 5更新(以及我的观点)

我认为这对JUnit来说是非常重要的功能，如果JUnit的作者不想要订单功能，为什么?

默认情况下，单元测试库不会尝试按照源文件中出现的顺序执行测试。

JUnit 5和JUnit 4一样以这种方式工作。为什么?因为如果顺序很重要，这意味着一些测试在它们之间是耦合的，这对于单元测试来说是不可取的。 所以JUnit 5引入的@Nested特性遵循相同的默认方法。

But for integration tests, the order of the test method may matter since a test method may change the state of the application in a way expected by another test method. For example when you write an integration test for a e-shop checkout processing, the first test method to be executed is registering a client, the second is adding items in the basket and the last one is doing the checkout. If the test runner doesn't respect that order, the test scenario is flawed and will fail. So in JUnit 5 (from the 5.4 version) you have all the same the possibility to set the execution order by annotating the test class with @TestMethodOrder(OrderAnnotation.class) and by specifying the order with @Order(numericOrderValue) for the methods which the order matters.

例如:

@TestMethodOrder(OrderAnnotation.class) 
class FooTest {

    @Order(3)
    @Test
    void checkoutOrder() {
        System.out.println("checkoutOrder");
    }

    @Order(2)
    @Test
    void addItemsInBasket() {
        System.out.println("addItemsInBasket");
    }

    @Order(1)
    @Test
    void createUserAndLogin() {
        System.out.println("createUserAndLogin");
    }
}

输出:

创建用户和登录 添加物品在购物篮 结帐订单

顺便说一下，指定@TestMethodOrder(OrderAnnotation.class)看起来不需要(至少在我测试的5.4.0版本中是这样)。

边注 关于这个问题:JUnit 5是编写集成测试的最佳选择吗?我不认为它应该是首先考虑的工具(Cucumber和co可能经常为集成测试带来更具体的价值和特性)，但在一些集成测试用例中，JUnit框架就足够了。所以这个功能的存在是个好消息。

如果希望在JUnit 5中以特定顺序运行测试方法，可以使用下面的代码。

@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
public class MyClassTest { 

    @Test
    @Order(1)
    public void test1() {}

    @Test
    @Order(2)
    public void test2() {}

}

这是我在Junit工作时遇到的主要问题之一，我想出了以下解决方案，对我来说很好:

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import org.junit.runners.BlockJUnit4ClassRunner;
import org.junit.runners.model.FrameworkMethod;
import org.junit.runners.model.InitializationError;

public class OrderedRunner extends BlockJUnit4ClassRunner {

    public OrderedRunner(Class<?> clazz) throws InitializationError {
        super(clazz);
    }

    @Override
    protected List<FrameworkMethod> computeTestMethods() {
        List<FrameworkMethod> list = super.computeTestMethods();
        List<FrameworkMethod> copy = new ArrayList<FrameworkMethod>(list);
        Collections.sort(copy, new Comparator<FrameworkMethod>() {

            @Override
            public int compare(FrameworkMethod f1, FrameworkMethod f2) {
                Order o1 = f1.getAnnotation(Order.class);
                Order o2 = f2.getAnnotation(Order.class);

                if (o1 == null || o2 == null) {
                    return -1;
                }

                return o1.order() - o2.order();
            }
        });
        return copy;
    }
}

还可以创建如下界面:

 @Retention(RetentionPolicy.RUNTIME)


@Target({ ElementType.METHOD})

public @interface Order {
public int order();
}

现在假设你有一个类A，你写了几个测试用例，如下所示:

(@runWith=OrderRunner.class)
Class A{
@Test
@Order(order = 1)

void method(){

//do something

}

}

因此，执行将从名为“method()”的方法开始。 谢谢!

JUnit 4更新

从JUnit 4.13 @OrderWith开始，可以复制JUnit 5 @Order注释。这个解决方案与JUnit4的集成比@RunWith自定义BlockJUnit4ClassRunner实现更好。

下面是我如何用注释排序替换方法名排序(@FixMethodOrder(MethodSorters.NAME_ASCENDING))。

@OrderWith(OrderAnnotation.class)
public class MyTest {
    @Test
    @Order(-1)
    public void runBeforeNotAnnotatedTests() {}

    @Test
    public void notAnnotatedTestHasPriority0() {}

    @Test
    @Order(1)
    public void thisTestHasPriority1() {}

    @Test
    @Order(2)
    public void thisTestHasPriority2() {}
}

/**
 * JUnit 4 equivalent of JUnit 5's {@code org.junit.jupiter.api.Order}
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.METHOD })
public @interface Order {
    /**
     * Default order value for elements not explicitly annotated with {@code @Order}.
     *
     * @see Order#value
     */
    int DEFAULT = 0;

    /**
     * The order value for the annotated element.
     * <p>Elements are ordered based on priority where a lower value has greater
     * priority than a higher value. For example, {@link Integer#MAX_VALUE} has
     * the lowest priority.
     *
     * @see #DEFAULT
     */
    int value();
}

import org.junit.runner.Description;
import org.junit.runner.manipulation.Ordering;
import org.junit.runner.manipulation.Sorter;

/**
 * Order test methods by their {@link Order} annotation. The lower value has the highest priority.
 * The tests that are not annotated get the default value {@link Order#DEFAULT}.
 */
public class OrderAnnotation extends Sorter implements Ordering.Factory {
    public OrderAnnotation() {
        super(COMPARATOR);
    }

    @Override
    public Ordering create(Context context) {
        return this;
    }

    private static final Comparator<Description> COMPARATOR = Comparator.comparingInt(
            description -> Optional.ofNullable(description.getAnnotation(Order.class))
                                   .map(Order::value)
                                   .orElse(Order.DEFAULT));
}

未加注释的测试的默认优先级为0。具有相同优先级的测试顺序尚未确定。

要点:https://gist.github.com/jcarsique/df98e0bad9e88e8258c4ab34dad3c863

启发:

Aman Goel的回答是 由JUnit团队编写的测试执行顺序 JUnit 5源代码

如果您摆脱了现有的Junit实例，并在构建路径中下载Junit 4.11或更高版本，以下代码将按照它们的名称(升序排序)执行测试方法:

import org.junit.FixMethodOrder;
import org.junit.Test;
import org.junit.runners.MethodSorters;

@FixMethodOrder(MethodSorters.NAME_ASCENDING)
public class SampleTest {

    @Test
    public void testAcreate() {
        System.out.println("first");
    }
    @Test
    public void testBupdate() {
        System.out.println("second");
    }
    @Test
    public void testCdelete() {
        System.out.println("third");
    }
}