使用带有 Powermock 的 jacoco 离线检测时缺少 jacoco.exec 文件

Question

尽管post 显然展示了使用 powermock 和 jacoco 的解决方案，但我无法使其在一个非常简单的项目中工作 (available on GitHub)。

在我的情况下，测试正确执行，但缺少 jacoco.exec 文件，因此 jacoco 不检查覆盖率。

测试类：

@RunWith(PowerMockRunner.class)
@PrepareOnlyThisForTest(Util.class)
@PowerMockIgnore("org.jacoco.agent.rt.*")
public class UtilTest {

    @Test
    public void testSay() throws Exception {
        PowerMockito.mockStatic(Util.class);
        Mockito.when(Util.say(Mockito.anyString())).thenReturn("hello:mandy");
        Assert.assertEquals("hello:mandy", Util.say("sid"));
    }

}

Util.java

public class Util {

    private Util() {}

    public static String say(String s) {
        return "hello:"+s;
    }

}

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.codependent.jacocopower</groupId>
    <artifactId>jacoco-powermock</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>2.18.1</version>
                <configuration>
                    <systemPropertyVariables>
                        <jacoco-agent.destfile>target/jacoco.exec</jacoco-agent.destfile>
                    </systemPropertyVariables>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.jacoco</groupId>
                <artifactId>jacoco-maven-plugin</artifactId>
                <version>${jacoco.version}</version>
                <executions>
                    <execution>
                        <id>default-instrument</id>
                        <goals>
                            <goal>instrument</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>default-restore-instrumented-classes</id>
                        <goals>
                            <goal>restore-instrumented-classes</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>default-report</id>
                        <phase>prepare-package</phase>
                        <goals>
                            <goal>report</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>default-check</id>
                        <goals>
                            <goal>check</goal>
                        </goals>
                        <configuration>
                            <rules>
                                <rule>
                                    <element>CLASS</element>
                                    <limits>
                                        <limit>
                                            <counter>LINE</counter>
                                            <value>COVEREDRATIO</value>
                                            <minimum>0.50</minimum>
                                        </limit>
                                    </limits>
                                </rule>
                            </rules>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

     <dependencies>
        <dependency>
            <groupId>org.jacoco</groupId>
            <artifactId>org.jacoco.agent</artifactId>
            <classifier>runtime</classifier>
            <version>${jacoco.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.powermock</groupId>
            <artifactId>powermock-module-junit4</artifactId>
            <version>${powermock.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.powermock</groupId>
            <artifactId>powermock-api-mockito</artifactId>
            <version>${powermock.version}</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.10</version>
            <scope>test</scope>
        </dependency>

    </dependencies>

    <properties>
        <powermock.version>1.5.4</powermock.version>
        <jacoco.version>0.7.4.201502262128</jacoco.version>
    </properties>

</project>

Maven 执行跟踪，抱怨找不到 jacoco.exec 文件：

>> mvn clean verify

[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building jacoco-powermock 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ jacoco-powermock ---
[INFO] Deleting C:\SoftDesarrollo\6-Workspaces\libertyGecon\jacoco-powermock\target
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ jacoco-powermock ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] Copying 0 resource
[INFO]
[INFO] --- maven-compiler-plugin:2.5.1:compile (default-compile) @ jacoco-powermock ---
[WARNING] File encoding has not been set, using platform encoding Cp1252, i.e. build is platform dependent!
[INFO] Compiling 1 source file to C:\SoftDesarrollo\6-Workspaces\libertyGecon\jacoco-powermock\target\classes
[INFO]
[INFO] --- jacoco-maven-plugin:0.7.4.201502262128:instrument (default-instrument) @ jacoco-powermock ---
[INFO]
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ jacoco-powermock ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] Copying 0 resource
[INFO]
[INFO] --- maven-compiler-plugin:2.5.1:testCompile (default-testCompile) @ jacoco-powermock ---
[WARNING] File encoding has not been set, using platform encoding Cp1252, i.e. build is platform dependent!
[INFO] Compiling 1 source file to C:\SoftDesarrollo\6-Workspaces\libertyGecon\jacoco-powermock\target\test-classes
[INFO]
[INFO] --- maven-surefire-plugin:2.18.1:test (default-test) @ jacoco-powermock ---
[INFO] Surefire report directory: C:\SoftDesarrollo\6-Workspaces\libertyGecon\jacoco-powermock\target\surefire-reports

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running com.codependent.jacoco.UtilTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.239 sec - in com.codependent.jacoco.UtilTest

Results :

Tests run: 1, Failures: 0, Errors: 0, Skipped: 0

[INFO]
[INFO] --- jacoco-maven-plugin:0.7.4.201502262128:restore-instrumented-classes (default-restore-instrumented-classes) @ jacoco-powermock ---
[INFO]
[INFO] --- jacoco-maven-plugin:0.7.4.201502262128:report (default-report) @ jacoco-powermock ---
[INFO] Skipping JaCoCo execution due to missing execution data file:C:\SoftDesarrollo\6-Workspaces\libertyGecon\jacoco-powermock\target\jacoco.exec
[INFO]
[INFO] --- maven-jar-plugin:2.4:jar (default-jar) @ jacoco-powermock ---
[INFO] Building jar: C:\SoftDesarrollo\6-Workspaces\libertyGecon\jacoco-powermock\target\jacoco-powermock-0.0.1-SNAPSHOT.jar
[INFO]
[INFO] --- jacoco-maven-plugin:0.7.4.201502262128:check (default-check) @ jacoco-powermock ---
[INFO] Skipping JaCoCo execution due to missing execution data file:C:\SoftDesarrollo\6-Workspaces\libertyGecon\jacoco-powermock\target\jacoco.exec
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.987s
[INFO] Finished at: Thu Jan 21 09:13:55 CET 2016
[INFO] Final Memory: 23M/331M
[INFO] ------------------------------------------------------------------------

更新：(here on GitHub)

根据 Lencalot 提供的答案，生成了 jacoco.exec 文件，但以下场景一直说 ServiceImpl 类覆盖率为 0%：

ServiceImpl

public class ServiceImpl implements Service{

    public String operation() {
        return Util.say("Hi!");
    }

}

服务测试

@RunWith(PowerMockRunner.class)
@PrepareForTest({Util.class})
public class ServiceTest {

    private Service service = new ServiceImpl();

    @Test
    public void testOperation() throws Exception {
        PowerMockito.mockStatic(Util.class);
        Mockito.when(Util.say(Mockito.anyString())).thenReturn("Bye!");
        Assert.assertEquals("Bye!", service.operation());
    }

}

追踪：

[WARNING] Rule violated for class com.codependent.jacoco.ServiceImpl: lines covered ratio is 0.00, but expected minimum is 0.50

Answer 1

<plugin>
    <groupId>org.jacoco</groupId>
    <artifactId>jacoco-maven-plugin</artifactId>
    <version>${jacoco.version}</version>
    <configuration>
        <append>true</append>
    </configuration>
    <executions>
        <execution>
            <id>default-instrument</id>
            <goals>
                <goal>instrument</goal>
            </goals>
            <configuration>
                <includes>
                    <include>**/*test*</include>
                </includes>
            </configuration>
        </execution>
        <execution>
            <id>default-restore-instrumented-classes</id>
            <goals>
                <goal>restore-instrumented-classes</goal>
            </goals>
            <configuration>
                <includes>
                    <include>**/*test*</include>
                </includes>
            </configuration>
        </execution>
        <execution>
            <id>Prepare-Jacoco</id>
            <goals>
                <goal>prepare-agent</goal>
            </goals>
            <configuration>
                <excludes>
                    <exclude>**/*test*</exclude>
                </excludes>
            </configuration>
        </execution>
    </executions>
</plugin>

您现在可以删除 Check，我们可以先尝试使其正常工作。

更新您的 Jacoco 依赖项，使其看起来像这样

<dependency>
    <groupId>org.jacoco</groupId>
    <artifactId>org.jacoco.agent</artifactId>
    <version>${jacoco.version}</version>
    <scope>test</scope>
</dependency> 

让你的maven surefire插件看起来像这样：

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <configuration>
        <argLine>${argLine}</argLine>
    </configuration>
</plugin>

在你的属性部分添加这个，然后改变你的 jacoco 版本：

<jacoco.version>0.7.5.201505241946</jacoco.version>
<jacoco.outputDir>${project.basedir}/target/jacoco.exec</jacoco.outputDir>

@codependent 这里有一个你为什么要模拟的例子。

让我们假设你的 Util.class 有更多的代码、很多的实例化，甚至可能涉及到一些服务器端的东西，甚至可能是一个 UI。您不想实例化 User.class 只是为了测试其他名为 UtilUser.class 的类中的单个方法

protected class UtilUser {
    protected UtilUser() {}

    public Boolean checkSay(String s) {
        String expectedString = "hello:" + s;
        String actualString = Util.say(s);

        if (expectedString.equals(actualString){
           return true;
        } else { 
           return false;
        }

    }
}

要对 UtilUser 进行单元测试，您需要访问所有分支。因此，在您的测试中，您将模拟 Util.class，并在一个单元测试中强制它返回正确的字符串，而在另一个测试中让它返回一个不正确的字符串。您不关心测试 User.class，您知道它会相应地运行，或者您将有另一个测试来处理它。对于 UtilUser 单元测试，您可以期望 Util 返回正确的字符串或不正确的字符串，并且您希望测试这两种可能性。

模拟有时间和地点，它们是一个很好的了解工具，但不要认为它们应该经常使用。请参考以下文章，它将让您深入了解何时应该使用模拟：When To Mock