[Forwardport] Creating custom customer attribute with default value 0 will cause not saving value for customer entity.

Author: al.kravchuk

app/code/Magento/Catalog/Model/Product/Attribute/Backend/Boolean.php

@@ -3,6 +3,8 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
+
 namespace Magento\Catalog\Model\Product\Attribute\Backend;
 
 use Magento\Catalog\Model\Product\Attribute\Source\Boolean as BooleanSource;
@@ -25,7 +27,9 @@ public function beforeSave($object)
         $attributeCode = $this->getAttribute()->getName();
         if ($object->getData('use_config_' . $attributeCode)) {
             $object->setData($attributeCode, BooleanSource::VALUE_USE_CONFIG);
+            return $this;
         }
-        return $this;
+
+        return parent::beforeSave($object);
     }
 }

app/code/Magento/Downloadable/Setup/Patch/Data/UpdateLinksExistDefaultAttributeValue.php

@@ -0,0 +1,82 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento\Downloadable\Setup\Patch\Data;
+
+use Magento\Eav\Setup\EavSetup;
+use Magento\Eav\Setup\EavSetupFactory;
+use Magento\Framework\Setup\ModuleDataSetupInterface;
+use Magento\Framework\Setup\Patch\DataPatchInterface;
+use Magento\Framework\Setup\Patch\PatchVersionInterface;
+
+/**
+ * Remove default value from links exist attribute.
+ */
+class UpdateLinksExistDefaultAttributeValue implements DataPatchInterface, PatchVersionInterface
+{
+    /**
+     * @var ModuleDataSetupInterface
+     */
+    private $moduleDataSetup;
+
+    /**
+     * @var EavSetupFactory
+     */
+    private $eavSetupFactory;
+
+    /**
+     * @param ModuleDataSetupInterface $moduleDataSetup
+     * @param EavSetupFactory $eavSetupFactory
+     */
+    public function __construct(
+        ModuleDataSetupInterface $moduleDataSetup,
+        EavSetupFactory $eavSetupFactory
+    ) {
+        $this->moduleDataSetup = $moduleDataSetup;
+        $this->eavSetupFactory = $eavSetupFactory;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function apply()
+    {
+        /** @var EavSetup $eavSetup */
+        $eavSetup = $this->eavSetupFactory->create(['setup' => $this->moduleDataSetup]);
+        // remove default value
+        $eavSetup->updateAttribute(
+            \Magento\Catalog\Model\Product::ENTITY,
+            'links_exist',
+            'default_value',
+            null
+        );
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public static function getDependencies()
+    {
+        return [InstallDownloadableAttributes::class];
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public static function getVersion()
+    {
+        return '2.0.3';
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getAliases()
+    {
+        return [];
+    }
+}

app/code/Magento/Eav/Model/Entity/Attribute/AbstractAttribute.php

@@ -3,6 +3,7 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
 
 namespace Magento\Eav\Model\Entity\Attribute;
 
@@ -418,7 +419,7 @@ public function getIsVisibleOnFront()
     /**
      * Returns default value
      *
-     * @return string|int|bool|float
+     * @return string|null
      * @codeCoverageIgnore
      */
     public function getDefaultValue()
@@ -812,7 +813,7 @@ public function getBackendTable()
             if ($this->isStatic()) {
                 $this->_dataTable = $this->getEntityType()->getValueTablePrefix();
             } else {
-                $backendTable = trim($this->_getData('backend_table'));
+                $backendTable = trim((string)$this->_getData('backend_table'));
                 if (empty($backendTable)) {
                     $entityTable = [$this->getEntityType()->getEntityTablePrefix(), $this->getBackendType()];
                     $backendTable = $this->getResource()->getTable($entityTable);

app/code/Magento/Eav/Model/Entity/Attribute/Backend/AbstractBackend.php

@@ -3,6 +3,7 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
 
 namespace Magento\Eav\Model\Entity\Attribute\Backend;
 
@@ -204,12 +205,12 @@ public function getEntityValueId($entity)
     /**
      * Retrieve default value
      *
-     * @return mixed
+     * @return string
      */
     public function getDefaultValue()
     {
         if ($this->_defaultValue === null) {
-            if ($this->getAttribute()->getDefaultValue()) {
+            if ($this->getAttribute()->getDefaultValue() !== null) {
                 $this->_defaultValue = $this->getAttribute()->getDefaultValue();
             } else {
                 $this->_defaultValue = "";
@@ -285,7 +286,7 @@ public function afterLoad($object)
     public function beforeSave($object)
     {
         $attrCode = $this->getAttribute()->getAttributeCode();
-        if (!$object->hasData($attrCode) && $this->getDefaultValue()) {
+        if (!$object->hasData($attrCode) && $this->getDefaultValue() !== '') {
             $object->setData($attrCode, $this->getDefaultValue());
         }
 
@@ -348,9 +349,8 @@ public function getAffectedFields($object)
     }
 
     /**
-     * By default attribute value is considered scalar that can be stored in a generic way
+     * By default attribute value is considered scalar that can be stored in a generic way {@inheritdoc}
      *
-     * {@inheritdoc}
      * @codeCoverageIgnore
      */
     public function isScalar()