JUnit 5 + AssertJ示例

浅浅的花香味﹌ 2023-02-15 05:07 9阅读 0赞

![assertj徽标][assertj]![assertj徽标][assertj]

在本文中，我们将向您展示如何使用[AssertJ][]编写测试断言。

*PS已通过JUnit 5.5.2和AssertJ 3.14.0测试*

pom.xml

<dependency>
    		<groupId>org.junit.jupiter</groupId>
    		<artifactId>junit-jupiter-engine</artifactId>
    		<version>5.5.2</version>
    		<scope>test</scope>
    	</dependency>
    		
    	<dependency>
    		<groupId>org.assertj</groupId>
    		<artifactId>assertj-core</artifactId>
    		<version>3.14.0</version>
    		<scope>test</scope>
    	</dependency>

## 1.对AssertJ的JUnit 5断言 ##

将JUnit 5断言转换为AssetJ很容易，请参见以下语法：

JUnit 5

assertEquals(expected, actual);
    
    assertEquals(expected, actual, "assertion desc");

AssertJ

assertThat(actual).isEqualTo(expected);
    
    assertThat(actual).as("assertion desc").isEqualTo(expected);

## 2. AssertJ ##

2.1使用AssertJ的一些典型测试断言– `String` ， `List` ， `Map`和`Exception` 。

AssertjTest.java

package com.mkyong.assertions.assertj;
    
    import org.assertj.core.api.InstanceOfAssertFactories;
    import org.assertj.core.data.Index;
    import org.junit.jupiter.api.Test;
    
    import java.util.Arrays;
    import java.util.HashMap;
    import java.util.List;
    import java.util.Map;
    
    import static org.assertj.core.api.Assertions.as;
    import static org.assertj.core.api.Assertions.assertThat;
    import static org.assertj.core.api.AssertionsForClassTypes.assertThatThrownBy;
    
    public class AssertjTest {
    
        // assert string
        @Test
        void test_string_ok() {
    
            String name = "I am Mkyong!";
    
            assertThat(name)
                    .as("if failed display this msg!")
                    .isEqualTo("I am Mkyong!")
                    .isEqualToIgnoringCase("I AM mkyong!")
                    .startsWith("I")
                    .endsWith("!")
                    .containsIgnoringCase("mkyong");
    
        }
    
        // assert list
        @Test
        void test_list_ok() {
    
            List<String> list = Arrays.asList("Java", "Rust", "Clojure");
    
            assertThat(list)
                    .hasSize(3)
                    .contains("Java", "Clojure")
                    .contains("Java", Index.atIndex(0))
                    .contains("Rust", Index.atIndex(1))
                    .contains("Clojure", Index.atIndex(2))
                    .doesNotContain("Node JS");
    
        }
    
        // assert map
        @Test
        void test_map_ok() {
    
            Map<String, Object> map = new HashMap<>();
            map.put("name", "mkyong");
    
            assertThat(map)
                    .hasSize(1)
                    .extractingByKey("name", as(InstanceOfAssertFactories.STRING))
                    .isEqualToIgnoringCase("mkyong")
                    .startsWith("mkyong");
    
            assertThat(map).extracting("name")
                    .isEqualTo("mkyong");
    
            Map<String, Object> map2 = new HashMap<>();
            map2.put("number", 999);
    
            assertThat(map2)
                    .hasSize(1)
                    .extractingByKey("number", as(InstanceOfAssertFactories.INTEGER))
                    .isEqualTo(999);
    
        }
    
    
        // assert exception
        @Test
        void test_exception_ok() {
    
            assertThatThrownBy(() -> divide(1, 0))
                    .isInstanceOf(ArithmeticException.class)
                    .hasMessageContaining("zero")
                    .hasMessage("/ by zero");
    
            assertThatThrownBy(() -> {
                List<String> list = Arrays.asList("one", "two");
                list.get(2);
            })
                    .isInstanceOf(IndexOutOfBoundsException.class)
                    .hasMessageContaining("Index 2 out of bounds");
    
        }
    
        int divide(int input, int divide) {
            return input / divide;
        }
    
    }

## 下载源代码 ##

> $ git clone [https://github.com/mkyong/junit-examples][https_github.com_mkyong_junit-examples]  
> $ cd junit5-examples  
> $检查src / test / java / com / mkyong / assertions / assertj / \*。java

# 参考文献 #

*  [AssertJ –流利的断言Java库][AssertJ]
 *  [将您的JUnit 5断言转换为AssertJ][JUnit 5_AssertJ]
 *  [JUnit 5断言][JUnit 5]

标签： [断言][Link 1] [assertj][assertj 1] [异常][Link 2] [junit 5][]

> 翻译自: [https://mkyong.com/junit5/junit-5-assertj-examples/][https_mkyong.com_junit5_junit-5-assertj-examples]

[assertj]: http://imgconvert.csdnimg.cn/aHR0cHM6Ly9ta3lvbmcuY29tL3dwLWNvbnRlbnQvdXBsb2Fkcy8yMDE5LzExL2Fzc2VydGotbG9nby5wbmc?x-oss-process=image/format,png
[AssertJ]: https://assertj.github.io/doc/
[https_github.com_mkyong_junit-examples]: https://github.com/mkyong/junit-examples
[JUnit 5_AssertJ]: https://joel-costigliola.github.io/assertj/assertj-core-converting-junit5-assertions-to-assertj.html
[JUnit 5]: https://junit.org/junit5/docs/current/user-guide/#writing-tests-assertions
[Link 1]: https://mkyong.com/tag/assertion/
[assertj 1]: https://mkyong.com/tag/assertj/
[Link 2]: https://mkyong.com/tag/exception/
[junit 5]: https://mkyong.com/tag/junit-5/
[https_mkyong.com_junit5_junit-5-assertj-examples]: https://mkyong.com/junit5/junit-5-assertj-examples/