ACP2E-3523: Issue with Default Attribute Option Value Behavior for Multiselect

Author: aplapana

app/code/Magento/Catalog/Controller/Adminhtml/Product/Attribute/Save.php

@@ -272,7 +272,15 @@ public function execute()
                 unset($data['reset_is-default_option']);
                 $data['default_value'] = null;
             } elseif (isset($data['default'])) {
-                $data['default_value'] = implode(",", $data['default']);
+                $defaultOptions = [];
+                foreach ($data['default'] as $defaultValue) {
+                    if (intval($defaultValue) > 0) {
+                        $defaultOptions[] = $defaultValue;
+                    }
+                }
+                if (!empty($defaultOptions)) {
+                    $data['default_value'] = implode(",", $defaultOptions);
+                }
             }
 
             $model->addData($data);

app/code/Magento/Catalog/Test/Mftf/Section/AdminCreateNewProductAttributeSection.xml

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
- /**
-  * Copyright © Magento, Inc. All rights reserved.
-  * See COPYING.txt for license details.
-  */
+/**
+ * Copyright 2019 Adobe
+ * All Rights Reserved.
+ */
 -->
 
 <sections xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
@@ -19,7 +19,7 @@
         <element name="secondOptionStoreView" type="input" selector="//td[@class='col-option_1'][3]/input"/>
         <element name="customStoreViewField" type="input" selector="input[value='{{fieldValue}}']" parameterized="true"/>
         <element name="adminOption" type="input" selector="//input[contains(@name,'option[value][option_{{row}}][0]')]" parameterized="true"/>
-        <element name="defaultRadioButton" type="radio" selector="//tr[{{row}}]//input[contains(@name,'default[]')]" parameterized="true"/>
+        <element name="defaultRadioButton" type="radio" selector="//tr[{{row}}]//input[contains(@name,'default[')]" parameterized="true"/>
         <element name="isRequired" type="checkbox" selector="//input[contains(@name,'is_required')]/..//label"/>
         <element name="advancedAttributeProperties" type="text" selector="//div[contains(@data-index,'advanced_fieldset')]"/>
         <element name="attributeCode" type="input" selector="//*[@class='admin__fieldset-wrapper-content admin__collapsible-content _show']//input[@name='attribute_code']"/>

app/code/Magento/ConfigurableProduct/Test/Mftf/Section/AdminNewAttributePanelSection.xml

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
- /**
-  * Copyright © Magento, Inc. All rights reserved.
-  * See COPYING.txt for license details.
-  */
+/**
+ * Copyright 2018 Adobe
+ * All Rights Reserved.
+ */
 -->
 
 <sections xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"