From 97ad6e0cda1daf31579b75f464fba9b135ba3549 Mon Sep 17 00:00:00 2001
From: Gerhard <potgieterg@gmail.com>
Date: Wed, 8 May 2013 12:59:48 +0200
Subject: [PATCH] Fix for 0 sale price not returning true in is_on_sale

---
 classes/abstracts/abstract-wc-product.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/classes/abstracts/abstract-wc-product.php b/classes/abstracts/abstract-wc-product.php
index 44111131492..9387e4cc062 100644
--- a/classes/abstracts/abstract-wc-product.php
+++ b/classes/abstracts/abstract-wc-product.php
@@ -636,7 +636,7 @@ class WC_Product {
 	 * @return bool
 	 */
 	function is_on_sale() {
-		return $this->sale_price && $this->sale_price == $this->price ? true : false;
+		return isset( $this->sale_price ) && $this->sale_price == $this->price ? true : false;
 	}