fix unary precendence error when silent mode is activated and unary node not defined yet

Author: ichiriac

dist/php-parser.js

@@ -1,4 +1,4 @@
-/*! php-parser - BSD3 License - 2017-03-06 */
+/*! php-parser - BSD3 License - 2017-03-08 */
 
 require=(function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
 // shim for using process in browser
@@ -366,7 +366,7 @@ AST.prototype.prepare = function(kind, parser) {
       if (out) { // shift with precedence
         result = out;
       }
-    } else if (result.kind === 'unary') {
+    } else if (result.kind === 'unary' && result.what) {
       var out = result.precedence(result.what);
       if (out) { // shift with precedence
         result = out;

dist/php-parser.min.js

@@ -1,6 +1,6 @@
 {
   "name": "php-parser",
-  "version": "2.0.1",
+  "version": "2.0.2",
   "description": "Parse PHP code and returns its AST",
   "main": "src/index.js",
   "scripts": {

dist/php-parser.min.js.map

@@ -181,7 +181,7 @@ AST.prototype.prepare = function(kind, parser) {
       if (out) { // shift with precedence
         result = out;
       }
-    } else if (result.kind === 'unary') {
+    } else if (result.kind === 'unary' && result.what) {
       var out = result.precedence(result.what);
       if (out) { // shift with precedence
         result = out;