Junit5中实现参数化测试

从Junit5开始，对参数化测试支持进行了大幅度的改进和提升。下面我们就一起来详细看看Junit5参数化测试的方法。

部署和依赖

和Junit4相比，Junit5框架更多在向测试平台演进。其核心组成也从以前的一个Junit的jar包更换成由多个模块组成。本文所需要依赖模块如下：

• junit-jupiter-engine: Junit的核心测试引擎
• junit-jupiter-params: 编写参数化测试所需要的依赖包
• junit-platform-launcher: 从IDE(InteliJ/Eclipses)等运行时所需要的启动器

另外，为了从Maven命令行工具中运行Juint,还需要junit-platform-surefire-provider包的依赖。

maven的pom.xml文件中添加如下来进行安装

<dependencies>
    <dependency>
        <groupId>org.junit.jupiter</groupId>
        <artifactId>junit-jupiter-engine</artifactId>
        <version>5.2.0</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.junit.jupiter</groupId>
        <artifactId>junit-jupiter-params</artifactId>
        <version>5.2.0</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.junit.platform</groupId>
        <artifactId>junit-platform-launcher</artifactId>
        <version>1.2.0</version>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-surefire-plugin</artifactId>
            <version>2.22</version>
        </plugin>
    </plugins>
</build>

Junit5 参数源详解

value source

value source是最简单的参数源，通过注解可以直接指定携带的运行参数。

• String values: @ValueSource(strings = {“foo”, “bar”, “baz”})
• Double values: @ValueSource(doubles = {1.5D, 2.2D, 3.0D})
• Long values: @ValueSource(longs = {2L, 4L, 8L})
• Integer values: @ValueSource(ints = {2, 4, 8})

示例代码如下：

import static org.junit.jupiter.api.Assertions.assertEquals;

import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.ValueSource;

public class ValueSourcesExampleTest {

  @ParameterizedTest
  @ValueSource(ints = {2, 4, 8})
  void testNumberShouldBeEven(int num) {
    assertEquals(0, num % 2);
  }

  @ParameterizedTest
  @ValueSource(strings = {"Radar", "Rotor", "Tenet", "Madam", "Racecar"})
  void testStringShouldBePalindrome(String word) {
    assertEquals(isPalindrome(word), true);
  }

  @ParameterizedTest
  @ValueSource(doubles = {2.D, 4.D, 8.D})
  void testDoubleNumberBeEven(double num) {
    assertEquals(0, num % 2);
  }

  boolean isPalindrome(String word) {
    return word.toLowerCase().equals(new StringBuffer(word.toLowerCase()).reverse().toString());
  }
}

输出

[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running qiucao.learning.ParaTest
[INFO] Tests run: 11, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.155 s - in qiucao.learning.ParaTest
[INFO]
[INFO] Results:
[INFO]
[INFO] Tests run: 11, Failures: 0, Errors: 0, Skipped: 0

Enum Source

枚举参数源，允许我们通过将参数值由给定Enum枚举类型传入。并可以通过制定约束条件或正则匹配来筛选传入参数

import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertTrue;

import java.util.EnumSet;
import java.util.concurrent.TimeUnit;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.EnumSource;
import org.junit.jupiter.params.provider.EnumSource.Mode;

public class EnumSourcesExampleTest {

  @ParameterizedTest(name = "[{index}] TimeUnit: {arguments}")
  @EnumSource(TimeUnit.class)
  void testTimeUnitMinimumNanos(TimeUnit unit) {
    assertTrue(unit.toMillis(2000000L) > 1);
  }

  @ParameterizedTest
  @EnumSource(value = TimeUnit.class, names = {"SECONDS", "MINUTES"})
  void testTimeUnitJustSecondsAndMinutes(TimeUnit unit) {
    assertTrue(EnumSet.of(TimeUnit.SECONDS, TimeUnit.MINUTES).contains(unit));
    assertFalse(EnumSet
        .of(TimeUnit.DAYS, TimeUnit.HOURS, TimeUnit.MILLISECONDS, TimeUnit.NANOSECONDS,
            TimeUnit.MICROSECONDS).contains(unit));
  }

  @ParameterizedTest
  @EnumSource(value = TimeUnit.class, mode = Mode.EXCLUDE, names = {"SECONDS", "MINUTES"})
  void testTimeUnitExcludingSecondsAndMinutes(TimeUnit unit) {
    assertFalse(EnumSet.of(TimeUnit.SECONDS, TimeUnit.MINUTES).contains(unit));
    assertTrue(EnumSet
        .of(TimeUnit.DAYS, TimeUnit.HOURS, TimeUnit.MILLISECONDS, TimeUnit.NANOSECONDS,
            TimeUnit.MICROSECONDS).contains(unit));
  }

  @ParameterizedTest
  @EnumSource(value = TimeUnit.class, mode = Mode.MATCH_ALL, names = ".*SECONDS")
  void testTimeUnitIncludingAllTypesOfSecond(TimeUnit unit) {
    assertFalse(EnumSet.of(TimeUnit.DAYS, TimeUnit.HOURS, TimeUnit.MINUTES).contains(unit));
    assertTrue(EnumSet
        .of(TimeUnit.SECONDS, TimeUnit.MILLISECONDS, TimeUnit.NANOSECONDS,
            TimeUnit.MICROSECONDS).contains(unit));
  }

}

输出：

[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running qiucao.learning.ParaTest
[INFO] Tests run: 18, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.206 s - in qiucao.learning.ParaTest
[INFO]
[INFO] Results:
[INFO]
[INFO] Tests run: 18, Failures: 0, Errors: 0, Skipped: 0

Method Source

通过其他的Java方法函数来作为参数源。引用的方法返回值必须是Stream, Iterator 或者Iterable.

import static org.junit.jupiter.api.Assertions.assertAll;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertTrue;

import java.util.stream.IntStream;
import java.util.stream.Stream;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.Arguments;
import org.junit.jupiter.params.provider.MethodSource;

public class MethodSourceExampleTest {
  @ParameterizedTest
  @MethodSource("stringGenerator")
  void shouldNotBeNullString(String arg){
    assertNotNull(arg);
  }

  @ParameterizedTest
  @MethodSource("intGenerator")
  void shouldBeNumberWithinRange(int arg){
    assertAll(
        () -> assertTrue(arg > 0),
        () -> assertTrue(arg <= 10)
    );
  }

  @ParameterizedTest(name = "[{index}] user with id: {0} and name: {1}")
  @MethodSource("userGenerator")
  void shouldUserWithIdAndName(long id, String name){
        assertNotNull(id);
        assertNotNull(name);
  }

  static Stream<String> stringGenerator(){
    return Stream.of("hello", "world", "let's", "test");
  }

  static IntStream intGenerator() {
    return IntStream.range(1,10);
  }

  static Stream<Arguments> userGenerator(){
    return Stream.of(Arguments.of(1L, "Sally"), Arguments.of(2L, "Terry"), Arguments.of(3L, "Fred"));
  }
}

输出：

[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running qiucao.learning.ParaTest
[INFO] Tests run: 16, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.191 s - in qiucao.learning.ParaTest
[INFO]
[INFO] Results:
[INFO]
[INFO] Tests run: 16, Failures: 0, Errors: 0, Skipped: 0

Argument Source

通过参数类来作为参数源。这里引用的类必须实现ArgumentsProvider接口。示例如下：

import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertTrue;

import java.util.stream.Stream;
import org.junit.jupiter.api.extension.ExtensionContext;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.Arguments;
import org.junit.jupiter.params.provider.ArgumentsProvider;
import org.junit.jupiter.params.provider.ArgumentsSource;

public class ArgumentsSourceExampleTest {

  @ParameterizedTest
  @ArgumentsSource(CustomArgumentsGenerator.class)
  void testGeneratedArguments(double number) throws Exception {
    assertFalse(number == 0.D);
    assertTrue(number > 0);
    assertTrue(number < 1);
  }

  static class CustomArgumentsGenerator implements ArgumentsProvider {

    @Override
    public Stream<? extends Arguments> provideArguments(ExtensionContext context) {
      return Stream.of(Math.random(), Math.random(), Math.random(), Math.random(), Math.random())
          .map(Arguments::of);
    }
  }
}

CSV Source

通过指定csv格式(comma-separated-values)的注解作为参数源

import static org.junit.jupiter.api.Assertions.assertTrue;

import java.util.HashMap;
import java.util.Map;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.CsvSource;

public class CsvSourceExampleTest {

  Map<Long, String> idToUsername = new HashMap<>();

  {
    idToUsername.put(1L, "Selma");
    idToUsername.put(2L, "Lisa");
    idToUsername.put(3L, "Tim");
  }

  @ParameterizedTest
  @CsvSource({"1,Selma", "2,Lisa", "3,Tim"})
  void testUsersFromCsv(long id, String name) {
    assertTrue(idToUsername.containsKey(id));
    assertTrue(idToUsername.get(id).equals(name));
  }
}

输出：

[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running qiucao.learning.ParaTest
[INFO] Tests run: 3, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.164 s - in qiucao.learning.ParaTest
[INFO]
[INFO] Results:
[INFO]
[INFO] Tests run: 3, Failures: 0, Errors: 0, Skipped: 0

CSV File Source

除了使用csv参数源，这里也支持使用csv文件作为参数源

假设users.csv 文件包含如下csv格式的数据

1,Selma
2,Lisa
3,Tim

代码示例如下

import static org.junit.jupiter.api.Assertions.assertTrue;

import java.util.HashMap;
import java.util.Map;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.CsvFileSource;
import org.junit.jupiter.params.provider.CsvSource;

public class CsvFileSourceExampleTest {

  Map<Long, String> idToUsername = new HashMap<>();

  {
    idToUsername.put(1L, "Selma");
    idToUsername.put(2L, "Lisa");
    idToUsername.put(3L, "Tim");
  }

  @ParameterizedTest
  @CsvFileSource(resources = "/users.csv")
  void testUsersFromCsv(long id, String name) {
    assertTrue(idToUsername.containsKey(id));
    assertTrue(idToUsername.get(id).equals(name));
  }
}

输出：

[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running qiucao.learning.ParaTest
[INFO] Tests run: 3, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.199 s - in qiucao.learning.ParaTest
[INFO]
[INFO] Results:
[INFO]
[INFO] Tests run: 3, Failures: 0, Errors: 0, Skipped: 0

参数转换

JUnit allows us to convert arguments to the target format we need in our tests.

There are two possible conversion types:

隐式转换

JUnit提供了很对内建的格式转化支持，特别是string和常用的数据类型

以下是支持和string型进行转换的类型

Boolean
Byte
Character
Short
Integer
Long
Float
Double
Enum subclass
Instant
LocalDate
LocalDateTime
LocalTime
OffsetTime
OffsetDateTime
Year
YearMonth
ZonedDateTime

显式转换

Junit5中可以使用@ConvertWith(MyConverter.class) 注解来实现 SimpleArgumentConverter.

代码示例：

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertTrue;

import java.time.LocalDate;
import java.time.Month;
import java.util.UUID;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.converter.ConvertWith;
import org.junit.jupiter.params.converter.SimpleArgumentConverter;
import org.junit.jupiter.params.provider.ValueSource;

public class ArgumentsConversionExampleTest {

  @ParameterizedTest
  @ValueSource(strings = "2017-07-11")
  void testImplicitArgumentConversion(LocalDate date) throws Exception {
    assertTrue(date.getYear() == 2017);
    assertTrue(date.getMonth().equals(Month.JULY));
    assertTrue(date.getDayOfMonth() == 11);
  }

  @ParameterizedTest
  @ValueSource(strings = "B4627B3B-ACC4-44F6-A2EB-FCC94DAB79A5")
  void testImplicitArgumentConversion(@ConvertWith(ToUUIDArgumentConverter.class) UUID uuid)
      throws Exception {
    assertNotNull(uuid);
    assertTrue(uuid.getLeastSignificantBits() == -6706989278516512347L);
  }

  static class ToUUIDArgumentConverter extends SimpleArgumentConverter {

    @Override
    protected Object convert(Object source, Class<?> targetType) {
      assertEquals(UUID.class, targetType, "may only convert to UUID");
      return UUID.fromString(String.valueOf(source));
    }
  }

}

输出：

[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running qiucao.learning.ParaTest
[INFO] Tests run: 2, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.487 s - in qiucao.learning.ParaTest
[INFO]
[INFO] Results:
[INFO]
[INFO] Tests run: 2, Failures: 0, Errors: 0, Skipped: 0

补充对照: JUnit 4中参数化测试方法

代码如下：

@RunWith(Parameterized.class)
public class ParameterizedTest {
    @Parameters(name = "Run #{index}: {0}^2={1}")
    public static Iterable<Object[]> data() {
        return Arrays.asList(new Object[][] { { 1, 1 }, { 2, 4 }, { 3, 9 },
                { 4, 16 }, { 5, 25 } });
    }

    private final int input;
    private final int resultExpected;

    public ParameterizedTest(final int input, final int result) {
        this.input = input;
        this.resultExpected = result;
    }

    @Test
    public void testUserMapping() {
        Calculator calc = new Calculator();
        assertEquals(resultExpected, calc.square(input));
    }
}

作者：城下秋草
链接：https://www.jianshu.com/p/477f2ded7ccc
来源：简书