Allowed the use of empty() and isset() in Controllers aliases propert…

…ies.

cake/libs/controller/controller.php

@@ -327,6 +327,24 @@ public function __construct($request = null) {
 		parent::__construct();
 	}
 
+/**
+ * Provides backwards compatbility avoid problems with empty and isset to alias properties.
+ *
+ * @return void
+ */
+	public function __isset($name) {
+		switch ($name) {
+			case 'base':
+			case 'here':
+			case 'webroot':
+			case 'data':
+			case 'action':
+			case 'params':
+				return true;
+		}
+		return false;
+	}
+
 /**
  * Provides backwards compatbility access to the request object properties.
  * Also provides the params alias.

cake/tests/cases/libs/controller/controller.test.php

@@ -1543,6 +1543,11 @@ function testPropertyBackwardsCompatibility() {
 		$this->assertEquals($request->here, $Controller->here);
 		$this->assertEquals($request->action, $Controller->action);
 
+		$this->assertFalse(empty($Controller->data));
+		$this->assertTrue(isset($Controller->data));
+		$this->assertTrue(empty($Controller->something));
+		$this->assertFalse(isset($Controller->something));
+
 		$this->assertEquals($request, $Controller->params);
 		$this->assertEquals($request->params['controller'], $Controller->params['controller']);
 	}