Map artifactMap = project.getArtifactMap();

        assertNotNull( artifactMap, "artifact-map should not be null." );
        assertEquals( 1, artifactMap.size(), "artifact-map should contain 1 element." );

        Artifact artifact = (Artifact) artifactMap.get( key );

        assertNotNull( artifact, "dependency artifact not found in map." );

        try (InputStream is = Files.newInputStream(pom)) {
            XMLStreamReader parser = new WstxInputFactory().createXMLStreamReader(is);
            if (parser.nextTag() == XMLStreamReader.START_ELEMENT
                    && parser.getLocalName().equals("project")) {
                for (int i = 0; i < parser.getAttributeCount(); i++) {
                    if ("root".equals(parser.getAttributeLocalName(i))) {

specific language governing permissions and limitations
under the License.
-->

<model>
  <groupId>foo</groupId>
  <artifactId>bar</artifactId>
  <name>Babar</name>
  <version>4.5</version>

  <!-- Build element should be inherited from the super model -->

    </default>
  </defaults>
  <classes>
    <class rootElement="true" xml.tagName="remoteResourcesBundle">
      <name>RemoteResourcesBundle</name>
      <version>1.1.0</version>
      <description>Root element of the remote-resources.xml file.</description>
      <fields>
        <field>
          <name>remoteResources</name>
          <version>1.1.0</version>
          <description>

                for (Plugin element : src) {
                    Object key = getPluginKey().apply(element);
                    managedPlugins.put(key, element);
                }

                List<Plugin> newPlugins = new ArrayList<>();
                for (Plugin element : target.getPlugins()) {
                    Object key = getPluginKey().apply(element);

  </defaults>
  <classes>
    <class rootElement="true" xml.tagName="supplementalDataModels" xsd.compositor="sequence">
      <name>SupplementalDataModel</name>
      <version>1.0.0</version>
      <description>Root element of the supplemental-models.xml file.</description>
      <fields>
        <field xml.listStyle="flat">
          <name>supplement</name>
          <version>1.0.0</version>

            }

            for (Repository element : dominant) {
                Object key = getRepositoryKey().apply(element);
                merged.put(key, element);
            }

            for (Repository element : recessive) {
                Object key = getRepositoryKey().apply(element);
                if (!merged.containsKey(key)) {
                    merged.put(key, element);
                }
            }

            <p><b>Note:</b> This will not automagically make a Mojo run when the plugin declaration is added
            to the POM. It merely enables the user to omit the {@code <phase>} element from the
            surrounding {@code <execution>} element.</p>
          </description>
        </field>
        <field>
          <name>executePhase</name>
          <version>1.0.0+</version>
          <type>String</type>

                for (Plugin element : tgt) {
                    Object key = getPluginKey().apply(element);
                    merged.put(key, element);
                }

                Map<Object, Plugin> added = new LinkedHashMap<>();

                for (Plugin element : src) {
                    Object key = getPluginKey().apply(element);
                    Plugin existing = merged.get(key);

  <name>Maven Integration Test :: MNG-3979</name>
  <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/>