From 1ce8357866ea4d0325d4307573fbbba5e2adab5e Mon Sep 17 00:00:00 2001
From: Ilya Sarantsev <ilya.sarantsev@gmail.com>
Date: Sat, 26 Aug 2017 22:42:29 +0300
Subject: [PATCH] Performance optimization for #1941 per @isiahmeadows
 suggestion

---
 render/hyperscript.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/render/hyperscript.js b/render/hyperscript.js
index ea56c893..00c438c9 100644
--- a/render/hyperscript.js
+++ b/render/hyperscript.js
@@ -6,6 +6,11 @@ var selectorParser = /(?:(^|#|\.)([^#\.\[\]]+))|(\[(.+?)(?:\s*=\s*("|'|)((?:\\["
 var selectorCache = {}
 var hasOwn = {}.hasOwnProperty
 
+function isEmpty(object) {
+	for (var key in object) if (hasOwn.call(object, key)) return false
+	return true
+}
+
 function compileSelector(selector) {
 	var match, tag = "div", classes = [], attrs = {}
 	while (match = selectorParser.exec(selector)) {
@@ -28,7 +33,7 @@ function execSelector(state, attrs, children) {
 	var hasAttrs = false, childList, text
 	var className = attrs.className || attrs.class
 
-	if (Object.keys(state.attrs).length && Object.keys(attrs).length) {
+	if (!isEmpty(state.attrs) && !isEmpty(attrs)) {
 		var newAttrs = {}
 
 		for(var key in attrs) {