@Override
 public void execute(final jetbrains.mps.openapi.editor.EditorContext context) {
   EditorComponent editorComponent = ((EditorComponent) context.getEditorComponent());
   SelectionManager selectionManager = editorComponent.getSelectionManager();
   Selection selection = selectionManager.getSelection();
   if (selection instanceof SingularSelection) {
     EditorCell selectedCell = ((SingularSelection) selection).getEditorCell();
     SNode selectedNode = selectedCell.getSNode();
     SNode topMostNodeInSingularContainment =
         findTopMostNodeWithSingularContainment(selectedNode);
     if (topMostNodeInSingularContainment != selectedNode) {
       EditorCell nodeCell = editorComponent.findNodeCell(topMostNodeInSingularContainment);
       if (nodeCell != null) {
         editorComponent.pushSelection(nodeCell);
         editorComponent.scrollToCell(nodeCell);
       }
     } else {
       Selection newSelection =
           selectionManager.createRangeSelection(selectedNode, selectedNode);
       if (newSelection instanceof NodeRangeSelection && selectedCell.isBigCell()) {
         newSelection = ((NodeRangeSelection) newSelection).enlargeSelection(myUp);
       }
       if (newSelection != null) {
         selectionManager.pushSelection(newSelection);
         newSelection.ensureVisible();
       }
     }
   } else if (selection instanceof NodeRangeSelection) {
     Selection newSelection = ((NodeRangeSelection) selection).enlargeSelection(myUp);
     if (newSelection != null) {
       selectionManager.pushSelection(newSelection);
       newSelection.ensureVisible();
     }
   }
 }
    private EditorCell findTarget(SelectionManager selectionManager) {
      Selection selection = selectionManager.getSelection();
      if (selection == null) {
        return null;
      }

      jetbrains.mps.openapi.editor.cells.EditorCell cell = selection.getSelectedCells().get(0);
      if (cell instanceof EditorCell_Label && !((EditorCell_Label) cell).isEverythingSelected()) {
        return (EditorCell) cell;
      }

      if (cell.getParent() == null) {
        return null;
      }

      while (cell.getParent() != null && cell.getParent().isTransparentCollection()) {
        cell = cell.getParent();
      }
      jetbrains.mps.openapi.editor.cells.EditorCell_Collection parent = cell.getParent();
      while (parent != null) {
        if (parent.isSelectable()) {
          while (parent.getParent() != null
              && parent.getParent().isTransparentCollection()
              && parent.getParent().isSelectable()) {
            parent = parent.getParent();
          }
          return (EditorCell) parent;
        }
        parent = parent.getParent();
      }
      return null;
    }
 private EditorCell findTarget(EditorComponent editorComponent) {
   Selection selection = editorComponent.getSelectionManager().getSelection();
   if (selection == null) {
     return null;
   }
   List<EditorCell> selectedCells = selection.getSelectedCells();
   EditorCell cell = selectedCells.get(selectedCells.size() - 1);
   return cell.getEndCell(CellConditions.SELECTABLE);
 }
 private EditorCell findTarget(SelectionManager selectionManager) {
   Selection selection = selectionManager.getSelection();
   if (selection == null) {
     return null;
   }
   EditorCell cell = selection.getSelectedCells().get(0);
   while (cell.getParent() != null) {
     cell = (EditorCell) cell.getParent();
   }
   if (cell instanceof EditorCell_Collection) {
     return cell.findChild(
         myHome ? CellFinders.FIRST_SELECTABLE_LEAF : CellFinders.LAST_SELECTABLE_LEAF);
   }
   return cell;
 }
 private EditorCell findTarget(SelectionManager selectionManager) {
   Selection selection = selectionManager.getSelection();
   if (selection == null) {
     return null;
   }
   List<EditorCell> selectedCells = selection.getSelectedCells();
   EditorCell cell = myHome ? selectedCells.get(0) : selectedCells.get(selectedCells.size() - 1);
   EditorCell leaf =
       myHome
           ? cell.getLeafToLeft(CellConditions.SELECTABLE)
           : cell.getLeafToRight(CellConditions.SELECTABLE);
   if (leaf != null) {
     return leaf;
   }
   return myHome
       ? cell.getPrevLeaf(CellConditions.SELECTABLE)
       : cell.getNextLeaf(CellConditions.SELECTABLE);
 }