Avoid Eclipse ignore garbage in Scala Maven project

Question

the only way I've found to have maven compile scala sources on the command line using mvn is to add the executions explicitly in the scala-maven-plugin.

  <plugin>
    <groupId>net.alchim31.maven</groupId>
    <artifactId>scala-maven-plugin</artifactId>
    <version>3.0.1</version>
    <executions>
      <execution>
        <goals>
          <goal>compile</goal>
          <goal>testCompile</goal>
        </goals>
      </execution>
    </executions>
    <configuration>
      <args>
        <arg>-deprecation</arg>
        <arg>-unchecked</arg>
      </args>
      <jvmArgs>
        <jvmArg>-Xms128m</jvmArg>
        <jvmArg>-Xmx1024m</jvmArg>
      </jvmArgs>
    </configuration>
  </plugin>

However, Eclipse does not like these executions and gives the following errors.

Plugin execution not covered by lifecycle configuration: net.alchim31.maven:scala-maven-plugin:3.0.1:compile (execution: default, phase: compile)

Plugin execution not covered by lifecycle configuration: net.alchim31.maven:scala-maven-plugin:3.0.1:testCompile (execution: default, phase: test-compile)

Eclipse suggests permanently marking the goals as ignored, but this means a lot of ugly garbage is added to my pom. I mean, XML is already hard to look at. Is there a better way to configure my project to compile the sources with mvn? Following is what Eclipse adds.

<pluginManagement>
        <plugins>
            <!--This plugin's configuration is used to store Eclipse m2e settings only. It has no influence on the Maven build itself.-->
            <plugin>
                <groupId>org.eclipse.m2e</groupId>
                <artifactId>lifecycle-mapping</artifactId>
                <version>1.0.0</version>
                <configuration>
                    <lifecycleMappingMetadata>
                        <pluginExecutions>
                            <pluginExecution>
                                <pluginExecutionFilter>
                                    <groupId>
                                        net.alchim31.maven
                                    </groupId>
                                    <artifactId>
                                        scala-maven-plugin
                                    </artifactId>
                                    <versionRange>
                                        [3.0.1,)
                                    </versionRange>
                                    <goals>
                                        <goal>testCompile</goal>
                                        <goal>compile</goal>
                                    </goals>
                                </pluginExecutionFilter>
                                <action>
                                    <ignore></ignore>
                                </action>
                            </pluginExecution>
                        </pluginExecutions>
                    </lifecycleMappingMetadata>
                </configuration>
            </plugin>
        </plugins>
    </pluginManagement>

Answer 1

m2e requires you install specific m2e plugins. The one for scala-maven-plugin is m2e-scala: https://github.com/sonatype/m2eclipse-scala

Remove the pluginManagement that disables scala-maven-plugin, and install m2e-scala http://alchim31.free.fr/m2e-scala/update-site

BTW, latest scala-maven-plugin is 3.1.0, not 3.0.1.

Cheers,

Stéphane