code: function assertValidNodeInfo(descriptor) {
      if (descriptor.node) {
          assert(typeof descriptor.node === "object", "Node must be an object");
      } else {
          assert(descriptor.loc, "Node must be provided when reporting error if location is not provided");
      }
  }
docs: Asserts that either a loc or a node was provided, and the node is valid if it was provided.
  @param {MessageDescriptor} descriptor A descriptor to validate
  @returns {void}
  @throws AssertionError if neither a node nor a loc was provided, or if the node is not an object