Review

Possible null pointer dereference of addingRoot variable which is obtained from Node.getParent().

• missing/condition/null_check

com/google/javascript/jscomp/NodeUtil.java

getAddingRoot(Node)

class NodeUtil {
  /**
   * Gets a Node at the top of the current scope where we can add new var
   * declarations as children.
   */
  private static Node getAddingRoot(Node n) {
    Node addingRoot = null;
    Node ancestor = n;
    while (null != (ancestor = ancestor.getParent())) {
      int type = ancestor.getType();
      if (type == Token.SCRIPT) {
        addingRoot = ancestor;
        break;
      } else if (type == Token.FUNCTION) {
        addingRoot = ancestor.getLastChild();
        break;
      }
    }

    // make sure that the adding root looks ok
    Preconditions.checkState(addingRoot.getType() == Token.BLOCK ||
        addingRoot.getType() == Token.SCRIPT);
    Preconditions.checkState(addingRoot.getFirstChild() == null ||
        addingRoot.getFirstChild().getType() != Token.SCRIPT);
    return addingRoot;
  }

}