Update for let and optional parameters

lib/handlebars/compiler/code-gen.js

@@ -1,14 +1,14 @@
 /*global define */
 import {isArray} from '../utils';
 
-var SourceNode;
+let SourceNode;
 
 try {
   /* istanbul ignore next */
   if (typeof define !== 'function' || !define.amd) {
     // We don't support this in AMD environments. For these environments, we asusme that
     // they are running on the browser and thus have no need for the source-map library.
-    var SourceMap = require('source-map');
+    let SourceMap = require('source-map');
     SourceNode = SourceMap.SourceNode;
   }
 } catch (err) {
@@ -49,9 +49,9 @@ if (!SourceNode) {
 
 function castChunk(chunk, codeGen, loc) {
   if (isArray(chunk)) {
-    var ret = [];
+    let ret = [];
 
-    for (var i = 0, len = chunk.length; i < len; i++) {
+    for (let i = 0, len = chunk.length; i < len; i++) {
       ret.push(codeGen.wrap(chunk[i], loc));
     }
     return ret;
@@ -77,7 +77,7 @@ CodeGen.prototype = {
   },
 
   merge: function() {
-    var source = this.empty();
+    let source = this.empty();
     this.each(function(line) {
       source.add(['  ', line, '\n']);
     });
@@ -85,21 +85,19 @@ CodeGen.prototype = {
   },
 
   each: function(iter) {
-    for (var i = 0, len = this.source.length; i < len; i++) {
+    for (let i = 0, len = this.source.length; i < len; i++) {
       iter(this.source[i]);
     }
   },
 
-  empty: function(loc) {
-    loc = loc || this.currentLocation || {start: {}};
+  empty: function(loc = this.currentLocation || {start: {}}) {
     return new SourceNode(loc.start.line, loc.start.column, this.srcFile);
   },
-  wrap: function(chunk, loc) {
+  wrap: function(chunk, loc = this.currentLocation || {start: {}}) {
     if (chunk instanceof SourceNode) {
       return chunk;
     }
 
-    loc = loc || this.currentLocation || {start: {}};
     chunk = castChunk(chunk, this, loc);
 
     return new SourceNode(loc.start.line, loc.start.column, this.srcFile, chunk);
@@ -121,18 +119,18 @@ CodeGen.prototype = {
   },
 
   objectLiteral: function(obj) {
-    var pairs = [];
+    let pairs = [];
 
-    for (var key in obj) {
+    for (let key in obj) {
       if (obj.hasOwnProperty(key)) {
-        var value = castChunk(obj[key], this);
+        let value = castChunk(obj[key], this);
         if (value !== 'undefined') {
           pairs.push([this.quotedString(key), ':', value]);
         }
       }
     }
 
-    var ret = this.generateList(pairs);
+    let ret = this.generateList(pairs);
     ret.prepend('{');
     ret.add('}');
     return ret;
@@ -140,9 +138,9 @@ CodeGen.prototype = {
 
 
   generateList: function(entries, loc) {
-    var ret = this.empty(loc);
+    let ret = this.empty(loc);
 
-    for (var i = 0, len = entries.length; i < len; i++) {
+    for (let i = 0, len = entries.length; i < len; i++) {
       if (i) {
         ret.add(',');
       }
@@ -154,7 +152,7 @@ CodeGen.prototype = {
   },
 
   generateArray: function(entries, loc) {
-    var ret = this.generateList(entries, loc);
+    let ret = this.generateList(entries, loc);
     ret.prepend('[');
     ret.add(']');