magento-engcom#101: Re-add SKU generation in case product is duplicated. Duplicate needs a SKU to be saved.

Author: pogster

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

@@ -72,6 +72,31 @@ public function validate($object)
         return true;
     }
 
+    /**
+     * Generate and set unique SKU to product
+     *
+     * @param Product $object
+     * @return void
+     */
+    protected function _generateUniqueSku($object)
+    {
+        $attribute = $this->getAttribute();
+        $entity = $attribute->getEntity();
+        $attributeValue = $object->getData($attribute->getAttributeCode());
+        $increment = null;
+        while (!$entity->checkAttributeUniqueValue($attribute, $object)) {
+            if ($increment === null) {
+                $increment = $this->_getLastSimilarAttributeValueIncrement($attribute, $object);
+            }
+            $sku = trim($attributeValue);
+            if (strlen($sku . '-' . ++$increment) > self::SKU_MAX_LENGTH) {
+                $sku = substr($sku, 0, -strlen($increment) - 1);
+            }
+            $sku = $sku . '-' . $increment;
+            $object->setData($attribute->getAttributeCode(), $sku);
+        }
+    }
+
     /**
      * Make SKU unique before save
      *
@@ -80,6 +105,37 @@ public function validate($object)
      */
     public function beforeSave($object)
     {
+        if ($object->getIsDuplicate()) {
+            $this->_generateUniqueSku($object);
+        }
         return parent::beforeSave($object);
     }
+
+    /**
+     * Return increment needed for SKU uniqueness
+     *
+     * @param \Magento\Eav\Model\Entity\Attribute\AbstractAttribute $attribute
+     * @param Product $object
+     * @return int
+     */
+    protected function _getLastSimilarAttributeValueIncrement($attribute, $object)
+    {
+        $connection = $this->getAttribute()->getEntity()->getConnection();
+        $select = $connection->select();
+        $value = $object->getData($attribute->getAttributeCode());
+        $bind = ['attribute_code' => trim($value) . '-%'];
+
+        $select->from(
+            $this->getTable(),
+            $attribute->getAttributeCode()
+        )->where(
+            $attribute->getAttributeCode() . ' LIKE :attribute_code'
+        )->order(
+            ['entity_id DESC', $attribute->getAttributeCode() . ' ASC']
+        )->limit(
+            1
+        );
+        $data = $connection->fetchOne($select, $bind);
+        return abs((int)str_replace($value, '', $data));
+    }
 }