Program: 138425
Project: 138425
Buggy source:
@Override public void fillContextMenu(IMenuManager menu){
  Iterator<?> iter=((TreeSelection)this.getContext().getSelection()).iterator();
  while (iter.hasNext()) {
    Object obj=iter.next();
    if (obj instanceof RepositoryNode) {
      if (ConnectionUtils.isMdmConnection(((RepositoryNode)obj).getObject())) {
        return;
      }
    }
 else {
      return;
    }
  }
  TreeSelection treeSelection=(TreeSelection)getContext().getSelection();
  if (treeSelection == null) {
    return;
  }
  Object firstElement=treeSelection.getFirstElement();
  RepositoryNode rNode=(RepositoryNode)firstElement;
  IFolder folder=WorkbenchUtils.getFolder(rNode);
  IFolder metadataFolder=ResourceManager.getMetadataFolder();
  if (!folder.getFullPath().toOSString().startsWith(metadataFolder.getFullPath().toOSString())) {
    return;
  }
  Object[] selectedObj=treeSelection.toArray();
  if (selectedObj.length < 2) {
    return;
  }
  List<Object> objects=new ArrayList<Object>();
  for (  Object obj : selectedObj) {
    RepositoryNode node=(RepositoryNode)obj;
    if (node instanceof DBConnectionRepNode) {
      Property property=((DBConnectionRepNode)node).getObject().getProperty();
      DatabaseConnectionItem databaseConnectionItem=(DatabaseConnectionItem)property.getItem();
      Connection databaseConnection=databaseConnectionItem.getConnection();
      objects.add(databaseConnection);
    }
 else     if (node instanceof DBCatalogRepNode) {
      Catalog catalog=((DBCatalogRepNode)node).getCatalog();
      objects.add(catalog);
    }
 else     if (node instanceof DBSchemaRepNode) {
      Schema schema=((DBSchemaRepNode)node).getSchema();
      objects.add(schema);
    }
 else     if (node instanceof DBTableRepNode) {
      TdTable tdTable=((DBTableRepNode)node).getTdTable();
      objects.add(tdTable);
    }
 else     if (node instanceof DBColumnRepNode) {
      TdColumn tdColumn=((DBColumnRepNode)node).getTdColumn();
      objects.add(tdColumn);
    }
  }
  selectionCompareAction.refreshSelectedObj(objects.get(0),objects.get(1));
  menu.add(selectionCompareAction);
}

Fixed version (ground truth):
@Override public void fillContextMenu(IMenuManager menu){
  Iterator<?> iter=((TreeSelection)this.getContext().getSelection()).iterator();
  while (iter.hasNext()) {
    Object obj=iter.next();
    if (obj instanceof RepositoryNode) {
      if (ConnectionUtils.isMdmConnection(((RepositoryNode)obj).getObject())) {
        return;
      }
    }
 else {
      return;
    }
  }
  TreeSelection treeSelection=(TreeSelection)getContext().getSelection();
  if (treeSelection == null) {
    return;
  }
  Object firstElement=treeSelection.getFirstElement();
  RepositoryNode rNode=(RepositoryNode)firstElement;
  IFolder folder=WorkbenchUtils.getFolder(rNode);
  IFolder metadataFolder=ResourceManager.getMetadataFolder();
  if (!folder.getFullPath().toOSString().startsWith(metadataFolder.getFullPath().toOSString())) {
    return;
  }
  Object[] selectedObj=treeSelection.toArray();
  if (selectedObj.length < 2) {
    return;
  }
  List<Object> objects=new ArrayList<Object>();
  for (  Object obj : selectedObj) {
    RepositoryNode node=(RepositoryNode)obj;
    if (node instanceof DBConnectionRepNode) {
      Property property=((DBConnectionRepNode)node).getObject().getProperty();
      DatabaseConnectionItem databaseConnectionItem=(DatabaseConnectionItem)property.getItem();
      Connection databaseConnection=databaseConnectionItem.getConnection();
      objects.add(databaseConnection);
    }
 else     if (node instanceof DBCatalogRepNode) {
      Catalog catalog=((DBCatalogRepNode)node).getCatalog();
      objects.add(catalog);
    }
 else     if (node instanceof DBSchemaRepNode) {
      Schema schema=((DBSchemaRepNode)node).getSchema();
      objects.add(schema);
    }
 else     if (node instanceof DBTableRepNode) {
      TdTable tdTable=((DBTableRepNode)node).getTdTable();
      objects.add(tdTable);
    }
 else     if (node instanceof DBColumnRepNode) {
      TdColumn tdColumn=((DBColumnRepNode)node).getTdColumn();
      objects.add(tdColumn);
    }
 else     if (node instanceof DFColumnRepNode) {
    }
  }
  if (2 == objects.size()) {
    selectionCompareAction.refreshSelectedObj(objects.get(0),objects.get(1));
    menu.add(selectionCompareAction);
  }
}