Merge branch 'MC-42942' of https://github.com/magento-l3/magento2ce into L3-PR-20210830

Author: ArtemVasyliev

app/code/Magento/ImportExport/Model/Export.php

@@ -194,7 +194,7 @@ public function export()
         if (isset($this->_data[self::FILTER_ELEMENT_GROUP])) {
             $this->addLogComment(__('Begin export of %1', $this->getEntity()));
             $result = $this->_getEntityAdapter()->setWriter($this->_getWriter())->export();
-            $countRows = substr_count(trim($result), "\n");
+            $countRows = substr_count($result, "\n");
             if (!$countRows) {
                 throw new \Magento\Framework\Exception\LocalizedException(__('There is no data for the export.'));
             }

app/code/Magento/ImportExport/Test/Unit/Model/ExportTest.php

@@ -34,6 +34,11 @@ class ExportTest extends TestCase
      */
     protected $_exportConfigMock;
 
+    /**
+     * @var AbstractEntity|MockObject
+     */
+    private $abstractMockEntity;
+
     /**
      * Return mock for \Magento\ImportExport\Model\Export class
      *
@@ -43,8 +48,7 @@ protected function _getMageImportExportModelExportMock()
     {
         $this->_exportConfigMock = $this->getMockForAbstractClass(ConfigInterface::class);
 
-        /** @var $abstractMockEntity \Magento\ImportExport\Model\Export\AbstractEntity */
-        $abstractMockEntity = $this->getMockForAbstractClass(
+        $this->abstractMockEntity = $this->getMockForAbstractClass(
             AbstractEntity::class,
             [],
             '',
@@ -75,28 +79,55 @@ protected function _getMageImportExportModelExportMock()
         $exportAdapterFac = $this->createMock(\Magento\ImportExport\Model\Export\Adapter\Factory::class);
         /** @var \Magento\ImportExport\Model\Export $mockModelExport */
         $mockModelExport = $this->getMockBuilder(Export::class)
-            ->setMethods(['getEntityAdapter', '_getEntityAdapter', '_getWriter'])
+            ->setMethods(['getEntityAdapter', '_getEntityAdapter', '_getWriter', 'setWriter'])
             ->setConstructorArgs([$logger, $filesystem, $this->_exportConfigMock, $entityFactory, $exportAdapterFac])
             ->getMock();
         $mockModelExport->expects(
             $this->any()
         )->method(
             'getEntityAdapter'
         )->willReturn(
-            $abstractMockEntity
+            $this->abstractMockEntity
         );
         $mockModelExport->expects(
             $this->any()
         )->method(
             '_getEntityAdapter'
         )->willReturn(
-            $abstractMockEntity
+            $this->abstractMockEntity
+        );
+        $mockModelExport->method(
+            'setWriter'
+        )->willReturn(
+            $this->abstractMockEntity
         );
         $mockModelExport->expects($this->any())->method('_getWriter')->willReturn($mockAdapterTest);
 
         return $mockModelExport;
     }
 
+    /**
+     * Tests that export doesn't use `trim` function while counting the number of exported rows.
+     *
+     * Using PHP `trim` function allocates the same amount of memory as export result and leads
+     * to `out of memory` error.
+     */
+    public function testExportDoesntTrimResult()
+    {
+        $model = $this->_getMageImportExportModelExportMock();
+        $this->abstractMockEntity->method('export')
+            ->willReturn("export data  \n\n");
+        $model->setData([
+            Export::FILTER_ELEMENT_GROUP => [],
+            'entity' => 'catalog_product'
+        ]);
+        $model->export();
+        $this->assertStringContainsString(
+            'Exported 2 rows',
+            var_export($model->getFormatedLogTrace(), true)
+        );
+    }
+
     /**
      * Test get file name with adapter file name
      */