From e1a49cfb6de5c2e78ec600566544d77bd10ecc3d Mon Sep 17 00:00:00 2001
From: Brandon Kelly <brandon@pixelandtonic.com>
Date: Fri, 22 Jun 2018 11:19:21 -0700
Subject: [PATCH] Fixes #16247: Cloning components will now clone their
 behaviors as well

---
 framework/CHANGELOG.md                            |  1 +
 framework/base/Component.php                      | 11 ++++-
 tests/framework/base/ComponentTest.php            |  3 +-
 tests/framework/behaviors/CloningBehaviorTest.php | 57 +++++++++++++++++++++++
 4 files changed, 69 insertions(+), 3 deletions(-)
 create mode 100644 tests/framework/behaviors/CloningBehaviorTest.php

diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index b9a8cfb..f352e8c 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -53,6 +53,7 @@ Yii Framework 2 Change Log
 - Enh #16054: Callback execution with mutex synchronization (zhuravljov)
 - Enh #16126: Allows to configure `Connection::dsn` by config array (leandrogehlen)
 - Chg #11397: `yii\i18n\MessageFormatter` polyfills and `yii\i18n\MessageFormatter::parse()` method were removed resulting in performance boost. See UPGRADE for compatibility notes (samdark)
+- Chg #16247: Cloning components will now clone their behaviors as well (brandonkelly)
 
 2.0.14.2 under development
 ------------------------
diff --git a/framework/base/Component.php b/framework/base/Component.php
index 7fae458..767e432 100644
--- a/framework/base/Component.php
+++ b/framework/base/Component.php
@@ -302,13 +302,20 @@ class Component extends BaseObject
 
     /**
      * This method is called after the object is created by cloning an existing one.
-     * It removes all behaviors because they are attached to the old object.
+     * It clones all behaviors as well, and attaches them to the new object.
      */
     public function __clone()
     {
         $this->_events = [];
         $this->_eventWildcards = [];
-        $this->_behaviors = null;
+
+        if ($this->_behaviors !== null) {
+            $behaviors = $this->_behaviors;
+            $this->_behaviors = null;
+            foreach ($behaviors as $name => $behavior) {
+                $this->attachBehavior($name, clone $behavior);
+            }
+        }
     }
 
     /**
diff --git a/tests/framework/base/ComponentTest.php b/tests/framework/base/ComponentTest.php
index 6f1501d..0d262ab 100644
--- a/tests/framework/base/ComponentTest.php
+++ b/tests/framework/base/ComponentTest.php
@@ -61,7 +61,8 @@ class ComponentTest extends TestCase
 
         $clone = clone $component;
         $this->assertNotSame($component, $clone);
-        $this->assertNull($clone->getBehavior('a'));
+        $this->assertNotNull($clone->getBehavior('a'));
+        $this->assertNotSame($behavior, $clone->getBehavior('a'));
         $this->assertFalse($clone->hasEventHandlers('test'));
         $this->assertFalse($clone->hasEventHandlers('foo'));
         $this->assertFalse($clone->hasEventHandlers('*'));
diff --git a/tests/framework/behaviors/CloningBehaviorTest.php b/tests/framework/behaviors/CloningBehaviorTest.php
new file mode 100644
index 0000000..af4d3e1
--- /dev/null
+++ b/tests/framework/behaviors/CloningBehaviorTest.php
@@ -0,0 +1,57 @@
+<?php
+/**
+ * @link http://www.yiiframework.com/
+ * @copyright Copyright (c) 2008 Yii Software LLC
+ * @license http://www.yiiframework.com/license/
+ */
+
+namespace yiiunit\framework\behaviors;
+
+use yii\base\Behavior;
+use yii\base\Model;
+use yiiunit\TestCase;
+
+/**
+ * Unit test for cloning behaviors when objects are cloned.
+ *
+ * @group behaviors
+ */
+class CloningBehaviorTest extends TestCase
+{
+    public function testCloningObjectsClonesBehaviors()
+    {
+        $model1 = new ModelWithBehavior();
+        $model1->myBehaviorProperty = 'foo';
+        $model2 = clone $model1;
+
+        $this->assertEquals($model1->myBehaviorProperty, $model2->myBehaviorProperty);
+    }
+}
+
+/**
+ * Test Model class with a behavior attached.
+ *
+ * @mixin BehaviorWithProperty
+ */
+class ModelWithBehavior extends Model
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function behaviors()
+    {
+        return [
+            'myBehavior' => BehaviorWithProperty::class
+        ];
+    }
+}
+
+/**
+ * Test Behavior class with property.
+ *
+ */
+class BehaviorWithProperty extends Behavior
+{
+    public $myBehaviorProperty;
+}
+