Merge branch '2.2-lazy-helpers' into 2.2

app/Controller/PagesController.php

@@ -38,12 +38,6 @@ class PagesController extends AppController {
  */
 	public $name = 'Pages';
 
-/**
- * Default helper
- *
- * @var array
- */
-	public $helpers = array('Html', 'Session');
 
 /**
  * This controller does not use a model

lib/Cake/Console/Templates/skel/Controller/PagesController.php

@@ -29,13 +29,6 @@
  */
 class PagesController extends AppController {
 
-/**
- * Default helper
- *
- * @var array
- */
-	public $helpers = array('Html');
-
 /**
  * This controller does not use a model
  *

lib/Cake/Controller/Controller.php

@@ -92,7 +92,7 @@ class Controller extends Object implements CakeEventListener {
  * @var mixed A single name as a string or a list of names as an array.
  * @link http://book.cakephp.org/2.0/en/controllers.html#components-helpers-and-uses
  */
-	public $helpers = array('Session', 'Html', 'Form');
+	public $helpers = array();
 
 /**
  * An instance of a CakeRequest object that contains information about the current request.

lib/Cake/Test/Case/View/HelperCollectionTest.php

@@ -67,6 +67,35 @@ class HelperCollectionTest extends CakeTestCase {
 		$this->assertTrue($this->Helpers->enabled('Html'));
 	}
 
+/**
+ * test lazy loading of helpers
+ *
+ * @return void
+ */
+	public function testLazyLoad() {
+		$result = $this->Helpers->Html;
+		$this->assertInstanceOf('HtmlHelper', $result);
+
+		$result = $this->Helpers->Form;
+		$this->assertInstanceOf('FormHelper', $result);
+
+		App::build(array('Plugin' => array(CAKE . 'Test' . DS . 'test_app' . DS . 'Plugin' . DS)));
+		$this->View->plugin = 'TestPlugin';
+		CakePlugin::load(array('TestPlugin'));
+		$result = $this->Helpers->OtherHelper;
+		$this->assertInstanceOf('OtherHelperHelper', $result);
+	}
+
+/**
+ * test lazy loading of helpers
+ *
+ * @expectedException MissingHelperException
+ * @return void
+ */
+	public function testLazyLoadException() {
+		$result = $this->Helpers->NotAHelper;
+	}
+
 /**
  * Tests loading as an alias
  *
@@ -149,8 +178,8 @@ class HelperCollectionTest extends CakeTestCase {
 		$this->assertEquals(array('Form', 'Html'), $result, 'loaded helpers is wrong');
 
 		$this->Helpers->unload('Html');
-		$this->assertFalse(isset($this->Helpers->Html));
-		$this->assertTrue(isset($this->Helpers->Form));
+		$this->assertNotContains('Html', $this->Helpers->attached());
+		$this->assertContains('Form', $this->Helpers->attached());
 
 		$result = $this->Helpers->attached();
 		$this->assertEquals(array('Form'), $result, 'loaded helpers is wrong');

lib/Cake/Test/Case/View/ViewTest.php

@@ -798,6 +798,20 @@ class ViewTest extends CakeTestCase {
 		$this->assertInstanceOf('FormHelper', $View->Form, 'Object type is wrong.');
 	}
 
+
+/**
+ * test lazy loading helpers
+ *
+ * @return void
+ */
+	public function testLazyLoadHelpers() {
+		$View = new View($this->PostsController);
+
+		$View->helpers = array();
+		$this->assertInstanceOf('HtmlHelper', $View->Html, 'Object type is wrong.');
+		$this->assertInstanceOf('FormHelper', $View->Form, 'Object type is wrong.');
+	}
+
 /**
  * test the correct triggering of helper callbacks
  *

lib/Cake/View/HelperCollection.php

@@ -43,6 +43,51 @@ class HelperCollection extends ObjectCollection implements CakeEventListener {
 		$this->_View = $view;
 	}
 
+/**
+ * Tries to lazy load a helper based on its name, if it cannot be found
+ * in the application folder, then it tries looking under the current plugin
+ * if any
+ *
+ * @param string $helper The helper name to be loaded
+ * @return boolean wheter the helper could be loaded or not
+ **/
+	public function __isset($helper) {
+		if (parent::__isset($helper)) {
+			return true;
+		}
+
+		try {
+			$this->load($helper);
+		} catch (MissingHelperException $exception) {
+			if ($this->_View->plugin) {
+				$this->load($this->_View->plugin . '.' . $helper);
+				return true;
+			}
+		}
+
+		if (!empty($exception)) {
+			throw $exception;
+		}
+
+		return true;
+	}
+
+/**
+ * Provide public read access to the loaded objects
+ *
+ * @param string $name Name of property to read
+ * @return mixed
+ */
+	public function __get($name) {
+		if ($result = parent::__get($name)) {
+			return $result;
+		}
+		if ($this->__isset($name)) {
+			return $this->_loaded[$name];
+		}
+		return null;
+	}
+
 /**
  * Loads/constructs a helper.  Will return the instance in the registry if it already exists.
  * By setting `$enable` to false you can disable callbacks for a helper.  Alternatively you

lib/Cake/View/View.php

@@ -784,9 +784,6 @@ class View extends Object {
  * @return mixed
  */
 	public function __get($name) {
-		if (isset($this->Helpers->{$name})) {
-			return $this->Helpers->{$name};
-		}
 		switch ($name) {
 			case 'base':
 			case 'here':
@@ -799,9 +796,12 @@ class View extends Object {
 				return $this->request;
 			case 'output':
 				return $this->Blocks->get('content');
-			default:
-				return $this->{$name};
 		}
+		if (isset($this->Helpers->{$name})) {
+			$this->{$name} = $this->Helpers->{$name};
+			return $this->Helpers->{$name};
+		}
+		return $this->{$name};
 	}
 
 /**