From 5b83012d1a684cb915c71b648dc5bb2324e5a334 Mon Sep 17 00:00:00 2001
From: Lovell Fuller <github@lovell.info>
Date: Tue, 21 Mar 2017 14:55:57 +0000
Subject: [PATCH] Wrap try/catch with function to allow V8 to optimise
 onclosetag Improves performance of this 'hot' function by ~20% Improves
 overall XML to JS conversion throughput by ~2%

---
 lib/parser.js     | 19 +++++++++++--------
 src/parser.coffee | 11 +++++++----
 2 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/lib/parser.js b/lib/parser.js
index fbb961dc..e72578a5 100644
--- a/lib/parser.js
+++ b/lib/parser.js
@@ -1,4 +1,4 @@
-// Generated by CoffeeScript 1.11.1
+// Generated by CoffeeScript 1.12.4
 (function() {
   "use strict";
   var bom, defaults, events, isEmpty, processItem, processors, sax, setImmediate,
@@ -170,7 +170,7 @@
       })(this);
       this.saxParser.onclosetag = (function(_this) {
         return function() {
-          var cdata, emptyStr, err, key, node, nodeName, obj, objClone, old, s, xpath;
+          var cdata, emptyStr, key, node, nodeName, obj, objClone, old, s, xpath;
           obj = stack.pop();
           nodeName = obj["#name"];
           if (!_this.options.explicitChildren || !_this.options.preserveChildrenOrder) {
@@ -209,12 +209,15 @@
               }
               return results;
             })()).concat(nodeName).join("/");
-            try {
-              obj = _this.options.validator(xpath, s && s[nodeName], obj);
-            } catch (error1) {
-              err = error1;
-              _this.emit("error", err);
-            }
+            (function() {
+              var err;
+              try {
+                return obj = _this.options.validator(xpath, s && s[nodeName], obj);
+              } catch (error1) {
+                err = error1;
+                return _this.emit("error", err);
+              }
+            })();
           }
           if (_this.options.explicitChildren && !_this.options.mergeAttrs && typeof obj === 'object') {
             if (!_this.options.preserveChildrenOrder) {
diff --git a/src/parser.coffee b/src/parser.coffee
index 8673ec3f..8a375197 100644
--- a/src/parser.coffee
+++ b/src/parser.coffee
@@ -149,10 +149,13 @@ class exports.Parser extends events.EventEmitter
 
       if @options.validator?
         xpath = "/" + (node["#name"] for node in stack).concat(nodeName).join("/")
-        try
-          obj = @options.validator(xpath, s and s[nodeName], obj)
-        catch err
-          @emit "error", err
+        # Wrap try/catch with an inner function to allow V8 to optimise the containing function
+        # See https://github.com/Leonidas-from-XIV/node-xml2js/pull/369
+        do =>
+          try
+            obj = @options.validator(xpath, s and s[nodeName], obj)
+          catch err
+            @emit "error", err
 
       # put children into <childkey> property and unfold chars if necessary
       if @options.explicitChildren and not @options.mergeAttrs and typeof obj is 'object'