Program: 95461
Project: 95461
Buggy source:
/** 
 * @param sourceViewer The viewer containing the dragged/cut item.
 * @param targetViewer The viewer to which the item is to be dropped/pasted.
 * @param toDrop The items that were dragged/cut.
 * @param dropTarget The drop/paste target.
 * @param allowFromBrowser Whether items from the Test Case Browser are allowed to be dropped/pasted.
 * @return <code>true</code> if the given information indicates that thedrop/paste is valid. Otherwise <code>false</code>.
 */
public static boolean validateDrop(Viewer sourceViewer,Viewer targetViewer,IStructuredSelection toDrop,INodePO dropTarget,boolean allowFromBrowser){
  if (toDrop == null || toDrop.isEmpty() || dropTarget == null) {
    return false;
  }
  if (sourceViewer != null && !sourceViewer.equals(targetViewer)) {
    boolean foundOne=false;
    for (    TestCaseBrowser tcb : MultipleTCBTracker.getInstance().getOpenTCBs()) {
      if (sourceViewer.equals(tcb.getTreeViewer())) {
        foundOne=true;
      }
    }
    if (!(allowFromBrowser && foundOne)) {
      return false;
    }
  }
  Iterator iter=toDrop.iterator();
  INodePO par=null;
  while (iter.hasNext()) {
    Object obj=iter.next();
    if (!(obj instanceof INodePO) || obj instanceof IAbstractContainerPO) {
      return false;
    }
    if (obj instanceof IControllerPO && !(dropTarget instanceof ISpecTestCasePO) && !(dropTarget.getParentNode() instanceof ISpecTestCasePO)) {
      return false;
    }
    INodePO transferGUI=(INodePO)obj;
    INodePO parentNode=transferGUI.getParentNode();
    if (par != null && par != parentNode) {
      return false;
    }
    par=parentNode;
    if (!(transferGUI instanceof ISpecTestCasePO) && transferGUI.getSpecAncestor() != dropTarget.getSpecAncestor()) {
      return false;
    }
    if (!(transferGUI instanceof ISpecTestCasePO)) {
      continue;
    }
    ISpecTestCasePO specTcGUI=(ISpecTestCasePO)dropTarget.getSpecAncestor();
    if (transferGUI.hasCircularDependences(specTcGUI)) {
      return false;
    }
  }
  return true;
}

Fixed version (ground truth):
/** 
 * @param sourceViewer The viewer containing the dragged/cut item.
 * @param targetViewer The viewer to which the item is to be dropped/pasted.
 * @param toDrop The items that were dragged/cut.
 * @param dropTarget The drop/paste target.
 * @param allowFromBrowser Whether items from the Test Case Browser are allowed to be dropped/pasted.
 * @return <code>true</code> if the given information indicates that thedrop/paste is valid. Otherwise <code>false</code>.
 */
public static boolean validateDrop(Viewer sourceViewer,Viewer targetViewer,IStructuredSelection toDrop,INodePO dropTarget,boolean allowFromBrowser){
  if (toDrop == null || toDrop.isEmpty() || dropTarget == null) {
    return false;
  }
  if (sourceViewer != null && !sourceViewer.equals(targetViewer)) {
    boolean foundOne=false;
    for (    TestCaseBrowser tcb : MultipleTCBTracker.getInstance().getOpenTCBs()) {
      if (sourceViewer.equals(tcb.getTreeViewer())) {
        foundOne=true;
      }
    }
    if (!(allowFromBrowser && foundOne)) {
      return false;
    }
  }
  Iterator iter=toDrop.iterator();
  while (iter.hasNext()) {
    Object obj=iter.next();
    if (!(obj instanceof INodePO) || obj instanceof IAbstractContainerPO) {
      return false;
    }
    if (obj instanceof IControllerPO && !(dropTarget instanceof ISpecTestCasePO) && !(dropTarget.getParentNode() instanceof ISpecTestCasePO)) {
      return false;
    }
    INodePO transferGUI=(INodePO)obj;
    if (!(transferGUI instanceof ISpecTestCasePO) && transferGUI.getSpecAncestor() != dropTarget.getSpecAncestor()) {
      return false;
    }
    if (!(transferGUI instanceof ISpecTestCasePO)) {
      continue;
    }
    ISpecTestCasePO specTcGUI=(ISpecTestCasePO)dropTarget.getSpecAncestor();
    if (transferGUI.hasCircularDependences(specTcGUI)) {
      return false;
    }
  }
  return true;
}