Review

Iterator.next() is invoked without prior check that the iterator has more elements.

• missing/condition/value_or_state

com/google/javascript/jscomp/ReplaceMessages.java

constructAddOrStringNode(Iterator, Node)

class ReplaceMessages {
  /**
   * Creates a parse tree corresponding to the remaining message parts in
   * an iteration. The result will contain only STRING nodes, NAME nodes
   * (corresponding to placeholder references), and/or ADD nodes used to
   * combine the other two types.
   *
   * @param partsIterator  an iterator over message parts
   * @param argListNode  an LP node whose children are valid placeholder names
   * @return the root of the constructed parse tree
   *
   * @throws MalformedException if {@code partsIterator} contains a
   *   placeholder reference that does not correspond to a valid argument in
   *   the arg list
   */
  private Node constructAddOrStringNode(Iterator<CharSequence> partsIterator,
                                        Node argListNode)
      throws MalformedException {
    CharSequence part = partsIterator.next();
    Node partNode = null;
    if (part instanceof JsMessage.PlaceholderReference) {
      JsMessage.PlaceholderReference phRef =
          (JsMessage.PlaceholderReference) part;
      for (Node node : argListNode.children()) {
        if (node.getType() == Token.NAME) {
          String arg = node.getString();
          // We ignore the case here because the transconsole only supports
          // uppercase placeholder names, but function arguments in javascript
          // code can have mixed case.
          if (arg.equalsIgnoreCase(phRef.getName())) {
            partNode = Node.newString(Token.NAME, arg);
          }
        }
      }
      if (partNode == null) {
        throw new MalformedException(
            "Unrecognized message placeholder referenced: " + phRef.getName(),
            argListNode);
      }
    } else {
      // The part is just a string literal.
      partNode = Node.newString(part.toString());
    }
    if (partsIterator.hasNext()) {
      return new Node(Token.ADD, partNode,
                      constructAddOrStringNode(partsIterator, argListNode));
    } else {
      return partNode;
    }
  }
}