pom.xml

<?xml version="1.0" encoding="UTF-8"?>

<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>org.example</groupId>
  <artifactId>groovy-playground</artifactId>
  <version>1.0-SNAPSHOT</version>

  <name>groovy-playground</name>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>11</maven.compiler.source>
    <maven.compiler.target>11</maven.compiler.target>
  </properties>

  <dependencies>
    <dependency>
      <groupId>org.junit.jupiter</groupId>
      <artifactId>junit-jupiter-engine</artifactId>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.codehaus.groovy</groupId>
      <artifactId>groovy-all</artifactId>
      <version>3.0.9</version>
      <type>pom</type> <!-- required JUST since Groovy 2.5.0 -->
    </dependency>
    <dependency>
      <groupId>org.assertj</groupId>
      <artifactId>assertj-core</artifactId>
      <!-- use 2.9.1 for Java 7 projects -->
      <version>3.11.1</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.spockframework</groupId>
      <artifactId>spock-core</artifactId>
      <scope>test</scope>
    </dependency>
  </dependencies>

  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>org.junit</groupId>
        <artifactId>junit-bom</artifactId>
        <version>5.8.1</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
      <dependency>
        <groupId>org.spockframework</groupId>
        <artifactId>spock-bom</artifactId>
        <version>2.0-groovy-3.0</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
    </dependencies>
  </dependencyManagement>

  <build>
    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
      <plugins>
        <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.1</version>
          <configuration>
            <source>11</source>
            <target>11</target>
          </configuration>
        </plugin>
        <plugin>
          <groupId>org.apache.maven.plugins</groupId>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>3.0.0-M5</version>
          <configuration>
            <useModulePath>false</useModulePath> <!-- https://issues.apache.org/jira/browse/SUREFIRE-1809 -->
            <useFile>false</useFile>
            <includes>
              <include>**/*Test</include>
              <include>**/*Spec</include>
            </includes>
          </configuration>
        </plugin>
      </plugins>
    </pluginManagement>
    <plugins>
      <plugin>
        <artifactId>maven-antrun-plugin</artifactId>
        <version>3.0.0</version>
        <executions>
          <execution>
            <id>compile</id>
            <phase>compile</phase>
            <configuration>
              <target>
                <mkdir dir="${basedir}/src/main/groovy"/>
                <taskdef name="groovyc"
                         classname="org.codehaus.groovy.ant.Groovyc">
                  <classpath refid="maven.compile.classpath"/>
                </taskdef>
                <mkdir dir="${project.build.outputDirectory}"/>
                <groovyc destdir="${project.build.outputDirectory}"
                         srcdir="${basedir}/src/main/groovy/" listfiles="true">
                  <classpath refid="maven.compile.classpath"/>
                </groovyc>
              </target>
            </configuration>
            <goals>
              <goal>run</goal>
            </goals>
          </execution>
          <execution>
            <id>test-compile</id>
            <phase>test-compile</phase>
            <configuration>
              <target>
                <mkdir dir="${basedir}/src/test/groovy"/>
                <taskdef name="groovyc"
                         classname="org.codehaus.groovy.ant.Groovyc">
                  <classpath refid="maven.test.classpath"/>
                </taskdef>
                <mkdir dir="${project.build.testOutputDirectory}"/>
                <groovyc destdir="${project.build.testOutputDirectory}"
                         srcdir="${basedir}/src/test/groovy/" listfiles="true">
                  <classpath refid="maven.test.classpath"/>
                </groovyc>
              </target>
            </configuration>
            <goals>
              <goal>run</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
</project>