From a30f861f2c53b888f41fe9242138f0e1e3147466 Mon Sep 17 00:00:00 2001
From: mark_story <mark@mark-story.com>
Date: Thu, 19 Sep 2013 21:43:59 -0400
Subject: [PATCH] Use array_key_exists instead of isset()

This allows contains() to work with null values.

Fixes #4083
---
 lib/Cake/Test/Case/Utility/HashTest.php | 6 ++++++
 lib/Cake/Utility/Hash.php               | 4 ++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/Cake/Test/Case/Utility/HashTest.php b/lib/Cake/Test/Case/Utility/HashTest.php
index 67adfc9db..ebfa9c520 100644
--- a/lib/Cake/Test/Case/Utility/HashTest.php
+++ b/lib/Cake/Test/Case/Utility/HashTest.php
@@ -593,6 +593,12 @@ class HashTest extends CakeTestCase {
 		);
 		$this->assertTrue(Hash::contains($b, $a));
 		$this->assertFalse(Hash::contains($a, $b));
+
+		$a = array(0 => 'test', 'string' => null);
+		$this->assertTrue(Hash::contains($a, array('string' => null)));
+
+		$a = array(0 => 'test', 'string' => null);
+		$this->assertTrue(Hash::contains($a, array('test')));
 	}
 
 /**
diff --git a/lib/Cake/Utility/Hash.php b/lib/Cake/Utility/Hash.php
index 8cc99977a..e12f14c5f 100644
--- a/lib/Cake/Utility/Hash.php
+++ b/lib/Cake/Utility/Hash.php
@@ -442,14 +442,14 @@ class Hash {
 			$val = $needle[$key];
 			unset($needle[$key]);
 
-			if (isset($data[$key]) && is_array($val)) {
+			if (array_key_exists($key, $data) && is_array($val)) {
 				$next = $data[$key];
 				unset($data[$key]);
 
 				if (!empty($val)) {
 					$stack[] = array($val, $next);
 				}
-			} elseif (!isset($data[$key]) || $data[$key] != $val) {
+			} elseif (!array_key_exists($key, $data) || $data[$key] != $val) {
 				return false;
 			}