Program: 96338
Project: 96338
Buggy source:
/** 
 * @param targetEditor The editor to which the item is to be dropped/pasted.
 * @param toDrop The items that were dragged/cut.
 * @param dropTarget The drop/paste target.
 * @param dropPosition One of the values defined in ViewerDropAdapter to indicate the drop position relative to the drop target.
 * @return <code>true</code> if the drop/paste was successful. Otherwise <code>false</code>.
 */
public static boolean performDrop(AbstractTestCaseEditor targetEditor,IStructuredSelection toDrop,INodePO dropTarget,int dropPosition){
  if (targetEditor.getEditorHelper().requestEditableState() != JBEditorHelper.EditableState.OK) {
    return false;
  }
  List<Object> selectedElements=toDrop.toList();
  Collections.reverse(selectedElements);
  Iterator iter=selectedElements.iterator();
  while (iter.hasNext()) {
    INodePO droppedNode=null;
    Object obj=iter.next();
    if (!(obj instanceof INodePO)) {
      return false;
    }
    INodePO node=(INodePO)obj;
    if (node instanceof ICapPO || node instanceof IExecTestCasePO) {
      INodePO target=dropTarget;
      if (target != node && (target instanceof ICapPO || target instanceof IExecTestCasePO)) {
        droppedNode=moveNode(node,target);
      }
    }
    if (node instanceof ISpecTestCasePO) {
      INodePO target=dropTarget;
      if (target != node) {
        try {
          if (target instanceof ICapPO || target instanceof IExecTestCasePO) {
            dropOnCAPorExecTc(node,target,dropPosition);
          }
 else           if (target instanceof ISpecTestCasePO) {
            dropOnSpecTc(node,target);
          }
 else           if (node instanceof ISpecTestCasePO && target instanceof ITestSuitePO) {
            dropOnTestsuite((ITestSuitePO)target,(ISpecTestCasePO)node);
          }
        }
 catch (        PMException e) {
          NodeEditorInput inp=(NodeEditorInput)targetEditor.getAdapter(NodeEditorInput.class);
          INodePO inpNode=inp.getNode();
          PMExceptionHandler.handlePMExceptionForMasterSession(e);
          if (!(e instanceof PMAlreadyLockedException && ((PMAlreadyLockedException)e).getLockedObject() != null && !((PMAlreadyLockedException)e).getLockedObject().equals(inpNode)) || !targetEditor.isDirty()) {
            try {
              targetEditor.reOpenEditor(inpNode);
            }
 catch (            PMException e1) {
              PMExceptionHandler.handlePMExceptionForEditor(e,targetEditor);
            }
          }
          return false;
        }
      }
    }
    postDropAction(droppedNode,targetEditor);
  }
  return true;
}

Fixed version (ground truth):
/** 
 * @param targetEditor The editor to which the item is to be dropped/pasted.
 * @param toDrop The item that was dragged/cut.
 * @param dropTarget The drop/paste target.
 * @param dropPosition One of the values defined in ViewerDropAdapter to indicate the drop position relative to the drop target.
 * @return <code>true</code> if the drop/paste was successful. Otherwise <code>false</code>.
 */
private static boolean performDrop(AbstractTestCaseEditor targetEditor,INodePO dropTarget,int dropPosition,ISpecTestCasePO toDrop){
  INodePO target=dropTarget;
  if (target != toDrop) {
    EditSupport editSupport=targetEditor.getEditorHelper().getEditSupport();
    try {
      if (target instanceof ICapPO || target instanceof IExecTestCasePO) {
        dropOnCAPorExecTc(editSupport,toDrop,target,dropPosition);
      }
 else       if (target instanceof ISpecTestCasePO) {
        dropOnSpecTc(editSupport,toDrop,target);
      }
 else       if (target instanceof ITestSuitePO) {
        dropOnTestsuite(editSupport,(ITestSuitePO)target,(ISpecTestCasePO)toDrop);
      }
    }
 catch (    PMException e) {
      NodeEditorInput inp=(NodeEditorInput)targetEditor.getAdapter(NodeEditorInput.class);
      INodePO inpNode=inp.getNode();
      PMExceptionHandler.handlePMExceptionForMasterSession(e);
      if (!(e instanceof PMAlreadyLockedException && ((PMAlreadyLockedException)e).getLockedObject() != null && !((PMAlreadyLockedException)e).getLockedObject().equals(inpNode)) || !targetEditor.isDirty()) {
        try {
          targetEditor.reOpenEditor(inpNode);
        }
 catch (        PMException e1) {
          PMExceptionHandler.handlePMExceptionForEditor(e,targetEditor);
        }
      }
      return false;
    }
  }
  return true;
}