getting code coverage for java code with scala tests

Question

The project is a multi module maven project with 90% of the source code written in Java (there's a small bit in Scala). The unit tests are 80/20 java/scala, and the integration tests are 20/80 java/scala.

I tried Clover, but (at this time) it doesn't support scala.

I tried Jacoco. First I ran into problems getting any results due to the mutli-module configuration, but now using Sonar I've got the java coverage shown (thanks http://www.aheritier.net/maven-failsafe-sonar-and-jacoco-are-in-a-boat/). I used timezra (http://timezra.blogspot.com/2013/10/jacoco-and-scala.html) with jacoco, but that only analyzed the small bit of source code that is scala.

I started to try Scoverage, but that seems to have the same problem as timezra (it analyzes scala-to-scala, not the mix that I have). I therefor haven't even tried scct or undercover.

Is there any tool that handles mixed java/scala?

Emma works by bytecode instrumentation, so maybe it would work? I haven't tried it though. — lmm, Jan 07 '15 at 08:32

score 3 · Answer 1 · answered Jan 07 '15 at 09:30

3

I would suggest to have two separate coverage tools for Java and Scala. More specifically, use Scoverage for Scala (with plugin for Sonar).

The reason is that for Java you would probably like to measure line coverage where for Scala it's much better to measure statement coverage. Simply said because there are many statements on a single line in Scala and you would like to measure which of them were invoked. I've written an article about this.

answered Jan 07 '15 at 09:30

Rado Buransky

3,252
18
25

Two separate coverage tools isn't working for me. What I'm finding is that with the my scala tests checking the java code, the coverage tools only do java-java or scala-scala. – GrandVizier Jan 07 '15 at 18:02
How do you use two tools? If I run jacoco for example on the project it gives me poor coverage on everything scala. How do you intergrate the two results to get a working result? – Assaf Mendelson Mar 02 '17 at 17:54

score 1 · Answer 2 · answered Jan 16 '15 at 19:24

to answer my own question, Jacoco does analyze coverage for Scala tests and Java code. I haven't seen anything that does the opposite (but we don't have any Java tests for Scala code, so that didn't matter).

As for combining coverage, Rado's answer of using two tools makes sense.

Here's the changes I did to my pom to get coverage. NOTE, I'm creating Jacoco reports when the test runs, then later using Sonar for more analysis:

properties:

    <!-- Jacoco and Sonar config properties   -->
    <sonar.java.coveragePlugin>jacoco</sonar.java.coveragePlugin>
    <sonar.dynamicAnalysis>reuseReports</sonar.dynamicAnalysis>
    <jacoco.version>0.7.2.201409121644</jacoco.version>
    <sonar-jacoco-listeners.version>1.4</sonar-jacoco-listeners.version>

    <jacoco.outputDir>${basedir}/target/</jacoco.outputDir>
    <jacoco.out.ut.file>jacoco-ut.exec</jacoco.out.ut.file>
    <jacoco.out.it.file>jacoco-it.exec</jacoco.out.it.file>

    <sonar.jacoco.reportPath>${jacoco.outputDir}/${jacoco.out.ut.file}</sonar.jacoco.reportPath>
    <sonar.jacoco.itReportPath>${jacoco.outputDir}/${jacoco.out.it.file}</sonar.jacoco.itReportPath>

Failsafe:

      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-failsafe-plugin</artifactId>
        <version>2.17</version>
        <configuration>
          <argLine>-Xms512m -Xmx1024m ${jacoco.agent.it.arg}</argLine>
          <properties>
            <property>
              <name>listener</name>
              <value>org.sonar.java.jacoco.JUnitListener</value>
            </property>
          </properties>
          <reportsDirectory>${jacoco.outputDir}/surefire-reports</reportsDirectory>
        </configuration>
        <executions>
          <execution>
            <goals>
              <goal>integration-test</goal>
              <goal>verify</goal>
            </goals>
          </execution>
        </executions>
      </plugin>

jacoco:

      <plugin>
        <groupId>org.jacoco</groupId>
        <artifactId>jacoco-maven-plugin</artifactId>
        <version>${jacoco.version}</version>
        <executions>
          <execution>
            <id>prepare-ut-agent</id>
            <phase>process-test-classes</phase>
            <goals>
              <goal>prepare-agent</goal>
            </goals>
            <configuration>
              <destFile>${sonar.jacoco.reportPath}</destFile>
              <propertyName>jacoco.agent.ut.arg</propertyName>
              <append>true</append>
            </configuration>
          </execution>
          <execution>
            <id>prepare-it-agent</id>
            <phase>pre-integration-test</phase>
            <goals>
              <goal>prepare-agent-integration</goal>
            </goals>
            <configuration>
              <destFile>${sonar.jacoco.itReportPath}</destFile>
              <propertyName>jacoco.agent.it.arg</propertyName>
              <append>true</append>
            </configuration>
          </execution>
          <execution>
            <id>default-report</id>
            <phase>package</phase>
            <goals>
              <goal>report</goal>
            </goals>
            <configuration>
              <dataFile>${sonar.jacoco.reportPath}</dataFile>
            </configuration>
          </execution>
          <execution>
            <id>integration-report</id>
            <phase>post-integration-test</phase>
            <goals>
              <goal>report-integration</goal>
            </goals>
            <configuration>
              <dataFile>${sonar.jacoco.itReportPath}</dataFile>
            </configuration>
          </execution>
        </executions>
      </plugin>

surefire:

        <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.17</version>
          <configuration>
            <argLine>${jacoco.agent.ut.arg} -Xms512m -Xmx1024m</argLine>
            <skipTests>false</skipTests>
            <properties>
              <property>
                <name>listener</name>
                <value>org.sonar.java.jacoco.JUnitListener</value>
              </property>
            </properties>
            <reportsDirectory>${jacoco.outputDir}/surefire-reports</reportsDirectory>
          </configuration>
        </plugin>

added dependencies:

    <dependency>
      <groupId>org.codehaus.sonar-plugins.java</groupId>
      <artifactId>sonar-jacoco-listeners</artifactId>
      <version>${sonar-jacoco-listeners.version}</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.codehaus.sonar.plugins</groupId>
      <artifactId>sonar-surefire-plugin</artifactId>
      <version>3.3.2</version>
      <scope>test</scope>
    </dependency>

score 0 · Answer 3 · answered Jan 20 '15 at 09:05

It is possible to see the mix of the two languages coverage. With sonar is not possible, because it only analyzes one kind of language.

If you use jenkins, and configure a step that collect coverage reports(Jacoco), you will see the mixing the two languages.

getting code coverage for java code with scala tests

3 Answers3