MC-19661: Export Products bug. I can't exclude attributes from CSV file.

Author: Roman Lytvynenko

app/code/Magento/CatalogImportExport/Model/Export/Product.php

@@ -712,6 +712,21 @@ public function _getHeaderColumns()
         return $this->_customHeadersMapping($this->rowCustomizer->addHeaderColumns($this->_headerColumns));
     }
 
+    /**
+     * Return non-system attributes
+
+     * @return array
+     */
+    private function getNonSystemAttributes()
+    {
+        $attrKeys = [];
+        foreach ($this->filterAttributeCollection($this->getAttributeCollection()) as $attribute) {
+            $attrKeys []= $attribute->getAttributeCode();
+        }
+
+        return array_diff($this->_getExportMainAttrCodes(), $this->_customHeadersMapping($attrKeys));
+    }
+
     /**
      * Set headers columns
      *
@@ -729,7 +744,10 @@ protected function setHeaderColumns($customOptionsData, $stockItemRows)
         ) ?
             array_intersect(
                 $this->_getExportMainAttrCodes(),
-                $this->_customHeadersMapping($this->_getExportAttrCodes())
+                array_merge(
+                    $this->_customHeadersMapping($this->_getExportAttrCodes()),
+                    $this->getNonSystemAttributes()
+                )
             ) :
             $this->_getExportMainAttrCodes();