Program: 73106
Project: 73106
Buggy source:
protected static int handleValidateTargetCanContainElementHandle(DesignElementHandle targetHandle,DesignElementHandle childHandle,boolean validateContainer){
  if (targetHandle instanceof CascadingParameterGroupHandle) {
    return childHandle.getContainer() == targetHandle ? CONTAIN_THIS : CONTAIN_NO;
  }
 else   if (targetHandle.canContain(DEUtil.getDefaultSlotID(targetHandle),childHandle)) {
    return CONTAIN_THIS;
  }
 else   if (targetHandle != childHandle && targetHandle instanceof ParameterGroupHandle && childHandle instanceof ParameterGroupHandle) {
    return CONTAIN_THIS;
  }
 else   if (targetHandle instanceof ReportDesignHandle && childHandle instanceof ThemeHandle) {
    return CONTAIN_THIS;
  }
 else   if (targetHandle.canContain(DEUtil.getDefaultContentName(targetHandle),childHandle)) {
    return CONTAIN_THIS;
  }
 else   if (validateContainer) {
    if (targetHandle.getContainer() == null) {
      return CONTAIN_NO;
    }
    if (targetHandle.getContainerSlotHandle() == null) {
      if (!targetHandle.getContainerPropertyHandle().getDefn().isList()) {
        return CONTAIN_NO;
      }
    }
 else     if (!targetHandle.getContainer().getDefn().getSlot(targetHandle.getContainerSlotHandle().getSlotID()).isMultipleCardinality()) {
      return CONTAIN_NO;
    }
    if (targetHandle.getClass().equals(childHandle.getClass())) {
      if (childHandle instanceof LevelHandle)       return CONTAIN_NO;
      return CONTAIN_PARENT;
    }
    if (targetHandle.getContainerSlotHandle() != null) {
      return targetHandle.getContainer().canContain(targetHandle.getContainerSlotHandle().getSlotID(),childHandle) ? CONTAIN_PARENT : CONTAIN_NO;
    }
 else     if (targetHandle.getContainerPropertyHandle() != null) {
      return targetHandle.getContainer().canContain(targetHandle.getContainerPropertyHandle().getPropertyDefn().getName(),childHandle) ? CONTAIN_PARENT : CONTAIN_NO;
    }
  }
  return CONTAIN_NO;
}

Fixed version (ground truth):
static int handleValidateTargetCanContainElementHandle(DesignElementHandle targetHandle,DesignElementHandle childHandle,boolean validateContainer){
  if (targetHandle instanceof CascadingParameterGroupHandle) {
    return childHandle.getContainer() == targetHandle ? CONTAIN_THIS : CONTAIN_NO;
  }
 else   if (targetHandle.canContain(DEUtil.getDefaultSlotID(targetHandle),childHandle)) {
    return CONTAIN_THIS;
  }
 else   if (targetHandle != childHandle && targetHandle instanceof ParameterGroupHandle && childHandle instanceof ParameterGroupHandle) {
    return CONTAIN_THIS;
  }
 else   if (targetHandle instanceof ReportDesignHandle && childHandle instanceof ThemeHandle) {
    return CONTAIN_THIS;
  }
 else   if (targetHandle.canContain(DEUtil.getDefaultContentName(targetHandle),childHandle)) {
    return CONTAIN_THIS;
  }
 else   if (validateContainer) {
    if (targetHandle.getContainer() == null) {
      return CONTAIN_NO;
    }
    if (targetHandle.getContainerSlotHandle() == null) {
      if (!targetHandle.getContainerPropertyHandle().getDefn().isList()) {
        return CONTAIN_NO;
      }
    }
 else     if (!targetHandle.getContainer().getDefn().getSlot(targetHandle.getContainerSlotHandle().getSlotID()).isMultipleCardinality()) {
      return CONTAIN_NO;
    }
    if (targetHandle.getClass().equals(childHandle.getClass())) {
      if (childHandle instanceof LevelHandle)       return CONTAIN_NO;
      return CONTAIN_PARENT;
    }
    if (targetHandle.getContainerSlotHandle() != null) {
      return targetHandle.getContainer().canContain(targetHandle.getContainerSlotHandle().getSlotID(),childHandle) ? CONTAIN_PARENT : CONTAIN_NO;
    }
 else     if (targetHandle.getContainerPropertyHandle() != null) {
      return targetHandle.getContainer().canContain(targetHandle.getContainerPropertyHandle().getPropertyDefn().getName(),childHandle) ? CONTAIN_PARENT : CONTAIN_NO;
    }
  }
  return CONTAIN_NO;
}