From aaa868f03bc91880ae256eaae37f341b432b735a Mon Sep 17 00:00:00 2001
From: brandonkelly <brandon@pixelandtonic.com>
Date: Fri, 29 Jun 2018 16:51:07 -0700
Subject: [PATCH] Fixed #3034
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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`craft\fields\data\MultiOptionsFieldData` no longer implements the `craft\base\Serializable` interface, as its `serialize()` method conflicted with PHP’s `Serializable` interface.
---
 CHANGELOG-v3.md                           |  1 +
 src/fields/BaseOptionsField.php           | 17 +++++++++++++++++
 src/fields/data/MultiOptionsFieldData.php | 20 +-------------------
 3 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/CHANGELOG-v3.md b/CHANGELOG-v3.md
index 709ebe476d6..474d4adecd4 100644
--- a/CHANGELOG-v3.md
+++ b/CHANGELOG-v3.md
@@ -9,6 +9,7 @@
 - Fixed a bug where user verification links could get mangled when emails were parsed as Markdown, if the verification code contained two or more underscores.
 - Fixed a bug where Craft was misinterpreting `X-Forwarded-For` headers as the user’s IP instead of the server’s IP. ([#3036](https://github.com/craftcms/cms/issues/3036))
 - Fixed a bug where Craft wasn’t auto-scrolling the content container when dragging items near a window edge. ([#2340](https://github.com/craftcms/cms/issues/2340))
+- Fixed a PHP error that occurred when loading a Debug Toolbar panel on a page that contained serialized Checkboxes or Multi-Select field data. ([#3034](https://github.com/craftcms/cms/issues/3034))
 
 ## 3.0.13.2 - 2018-06-27
 
diff --git a/src/fields/BaseOptionsField.php b/src/fields/BaseOptionsField.php
index bfc30114d89..f0b5729183b 100644
--- a/src/fields/BaseOptionsField.php
+++ b/src/fields/BaseOptionsField.php
@@ -194,6 +194,23 @@ public function normalizeValue($value, ElementInterface $element = null)
         return $value;
     }
 
+    /**
+     * @inheritdoc
+     */
+    public function serializeValue($value, ElementInterface $element = null)
+    {
+        if ($value instanceof MultiOptionsFieldData) {
+            $serialized = [];
+            foreach ($value as $selectedValue) {
+                /** @var OptionData $selectedValue */
+                $serialized[] = $selectedValue->value;
+            }
+            return Json::encode($serialized);
+        }
+
+        return parent::serializeValue($value, $element);
+    }
+
     /**
      * @inheritdoc
      */
diff --git a/src/fields/data/MultiOptionsFieldData.php b/src/fields/data/MultiOptionsFieldData.php
index 1f76b177b36..4da020108ea 100644
--- a/src/fields/data/MultiOptionsFieldData.php
+++ b/src/fields/data/MultiOptionsFieldData.php
@@ -7,16 +7,13 @@
 
 namespace craft\fields\data;
 
-use craft\base\Serializable;
-use craft\helpers\Json;
-
 /**
  * Multi-select option field data class.
  *
  * @author Pixel & Tonic, Inc. <support@pixelandtonic.com>
  * @since 3.0
  */
-class MultiOptionsFieldData extends \ArrayObject implements Serializable
+class MultiOptionsFieldData extends \ArrayObject
 {
     // Properties
     // =========================================================================
@@ -66,19 +63,4 @@ public function contains($value): bool
 
         return false;
     }
-
-    /**
-     * @inheritdoc
-     */
-    public function serialize()
-    {
-        $serialized = [];
-
-        foreach ($this as $selectedValue) {
-            /** @var OptionData $selectedValue */
-            $serialized[] = $selectedValue->value;
-        }
-
-        return Json::encode($serialized);
-    }
 }