}

        public List<String> getCycle() {
            return cycle;
        }

        @Override
        public String getMessage() {
            return super.getMessage() + " " + String.join(" --> ", cycle);
        }
    }

  <description>
    Test that during inheritance the merging/joining of subtrees with equal identifier doesn't crash if the parent
    POM has a non-empty element and the child POM has an empty element to join.
  </description>

  <properties>
    <prop0>test</prop0>
  </properties>

  <repositories>
    <repository>
      <id>equal-repo-id</id>
      <url>https://maven.apache.org/null</url>
      <snapshots>

        }
    }

    private Properties convertToProperties(final BuildResumptionData buildResumptionData) {
        Properties properties = new Properties();

        String value = String.join(PROPERTY_DELIMITER, buildResumptionData.getRemainingProjects());
        properties.setProperty(REMAINING_PROJECTS, value);

        return properties;
    }

    @Override

        thread.start();

        MavenSession m2 = new MavenSession(null, null, mavenExecutionRequest, null);
        defaultLegacySupport.setSession(m2);
        latch.countDown();
        thread.join();
        assertNull(myRunnable.getSession());
    }

    class MyRunnable implements Runnable {

        private volatile MavenSession session;

        public void run() {
            try {

                buffer.append(" (");
                join(buffer, details, "; ");
                buffer.append(")");
            }
        } else {
            buffer.append("(");
            buffer.append(nodeString);
            if (!details.isEmpty()) {
                buffer.append(" - ");
                join(buffer, details, "; ");
            }
            buffer.append(")");
        }

                buffer.append(" (");
                join(buffer, details, "; ");
                buffer.append(")");
            }
        } else {
            buffer.append("(");
            buffer.append(nodeString);
            if (!details.isEmpty()) {
                buffer.append(" - ");
                join(buffer, details, "; ");
            }
            buffer.append(")");
        }

                                        + ":" + goal)))));
        return goals.entrySet().stream()
                .collect(Collectors.toMap(Map.Entry::getKey, e -> new LifecyclePhase(String.join(",", e.getValue()))));
    }

    public Map<String, LifecyclePhase> getDefaultLifecyclePhases() {
        return defaultPhases;
    }

    @Deprecated
    public Map<String, String> getDefaultPhases() {

Contributing
------------

If you are interested in the development of Maven, please consult the
documentation first and afterward you are welcome to join the developers
mailing list to ask questions or discuss new ideas/features/bugs etc.

Take a look into the [contribution guidelines](CONTRIBUTING.md).

License
-------

  <description>
    Test that during inheritance the merging/joining of subtrees with equal identifier doesn't crash if the parent
    POM has a non-empty element and the child POM has an empty element to join.
  </description>

  <properties/>

  <repositories>
    <repository>
      <id>equal-repo-id</id>
      <url>file:///${basedir}/null</url>
      <snapshots/>
      <releases/>
    </repository>

        this.cycle = cycle;
    }

    public List<String> getCycle() {
        return cycle;
    }

    @Override
    public String getMessage() {
        return super.getMessage() + " " + String.join(" --> ", cycle);
    }