Ejemplo n.º 1
0
    /** If this is an assign to a variable or its property, return it. Otherwise, return null. */
    static Assign maybeCreateAssign(Node assignNode) {
      Preconditions.checkState(NodeUtil.isAssignmentOp(assignNode));

      // Skip one level of GETPROPs or GETELEMs.
      //
      // Don't skip more than one level, because then we get into
      // situations where assigns to properties of properties will always
      // trigger side-effects, and the variable they're on cannot be removed.
      boolean isPropAssign = false;
      Node current = assignNode.getFirstChild();
      if (NodeUtil.isGet(current)) {
        current = current.getFirstChild();
        isPropAssign = true;

        if (current.getType() == Token.GETPROP
            && current.getLastChild().getString().equals("prototype")) {
          // Prototype properties sets should be considered like normal
          // property sets.
          current = current.getFirstChild();
        }
      }

      if (current.getType() == Token.NAME) {
        return new Assign(assignNode, current, isPropAssign);
      }
      return null;
    }
Ejemplo n.º 2
0
    Assign(Node assignNode, Node nameNode, boolean isPropertyAssign) {
      Preconditions.checkState(NodeUtil.isAssignmentOp(assignNode));
      this.assignNode = assignNode;
      this.nameNode = nameNode;
      this.isPropertyAssign = isPropertyAssign;

      this.mayHaveSecondarySideEffects =
          assignNode.getParent().getType() != Token.EXPR_RESULT
              || NodeUtil.mayHaveSideEffects(assignNode.getFirstChild())
              || NodeUtil.mayHaveSideEffects(assignNode.getLastChild());
    }