</sourceFileExcludes>
          <!-- The above exclusion doesn't actually matter unless I prevent Javadoc from autodiscovering the source in the sourcepath, which defaults to the source directory :\ Boo for -sourcepath. -->
          <sourcepath>doesnotexist</sourcepath>

                base compile settings (in the root `pom.xml`) to enable MRJAR output.
              -->
              <compilerArgs combine.self="override">
                <arg>-sourcepath</arg>
                <arg>${project.basedir}/src</arg>
                <arg>--add-reads=com.google.common=ALL-UNNAMED</arg>
                <!-- https://errorprone.info/docs/installation#maven -->

                      https://issues.apache.org/jira/browse/MCOMPILER-174
                      (Compare what guava-gwt has to do for maven-javadoc-plugin.)
                  -->
                  <arg>-sourcepath</arg>
                  <arg>doesnotexist</arg>
                </compilerArgs>
              </configuration>
            </execution>
            <execution>
              <id>default-testCompile</id>