public static List<DomElement> getDefinedChildren(
      @NotNull final DomElement parent, final boolean tags, final boolean attributes) {
    if (parent instanceof MergedObject) {
      final SmartList<DomElement> result = new SmartList<>();
      parent.acceptChildren(
          new DomElementVisitor() {
            @Override
            public void visitDomElement(final DomElement element) {
              if (hasXml(element)) {
                result.add(element);
              }
            }
          });
      return result;
    }

    ProgressManager.checkCanceled();

    if (parent instanceof GenericAttributeValue) return Collections.emptyList();

    if (parent instanceof DomFileElement) {
      final DomFileElement element = (DomFileElement) parent;
      return tags ? Arrays.asList(element.getRootElement()) : Collections.<DomElement>emptyList();
    }

    final XmlElement xmlElement = parent.getXmlElement();
    if (xmlElement instanceof XmlTag) {
      XmlTag tag = (XmlTag) xmlElement;
      final DomManager domManager = parent.getManager();
      final SmartList<DomElement> result = new SmartList<>();
      if (attributes) {
        for (final XmlAttribute attribute : tag.getAttributes()) {
          if (!attribute.isValid()) {
            LOG.error("Invalid attr: parent.valid=" + tag.isValid());
            continue;
          }
          GenericAttributeValue element = domManager.getDomElement(attribute);
          if (checkHasXml(attribute, element)) {
            ContainerUtil.addIfNotNull(result, element);
          }
        }
      }
      if (tags) {
        for (final XmlTag subTag : tag.getSubTags()) {
          if (!subTag.isValid()) {
            LOG.error("Invalid subtag: parent.valid=" + tag.isValid());
            continue;
          }
          DomElement element = domManager.getDomElement(subTag);
          if (checkHasXml(subTag, element)) {
            ContainerUtil.addIfNotNull(result, element);
          }
        }
      }
      return result;
    }
    return Collections.emptyList();
  }
  public static List<XmlTag> findSubTags(
      @NotNull final XmlTag tag, final EvaluatedXmlName name, final XmlFile file) {
    if (!tag.isValid()) {
      throw new AssertionError("Invalid tag");
    }
    final XmlTag[] tags = tag.getSubTags();
    if (tags.length == 0) {
      return Collections.emptyList();
    }

    return ContainerUtil.findAll(
        tags,
        childTag -> {
          try {
            return isNameSuitable(
                name, childTag.getLocalName(), childTag.getName(), childTag.getNamespace(), file);
          } catch (PsiInvalidElementAccessException e) {
            if (!childTag.isValid()) {
              LOG.error(
                  "tag.getSubTags() returned invalid, "
                      + "tag="
                      + tag
                      + ", "
                      + "containing file: "
                      + tag.getContainingFile()
                      + "subTag.parent="
                      + childTag.getNode().getTreeParent());
              return false;
            }
            throw e;
          }
        });
  }