Fix error when generating urn catalog for empty misc.xml

app/code/Magento/Developer/Model/XmlCatalog/Format/PhpStorm.php

@@ -6,11 +6,11 @@
 
 namespace Magento\Developer\Model\XmlCatalog\Format;
 
+use Magento\Developer\Model\XmlCatalog\Format\PhpStorm\DomDocumentFactory;
 use Magento\Framework\Exception\FileSystemException;
 use Magento\Framework\Filesystem\Directory\ReadFactory;
 use Magento\Framework\Filesystem\Directory\ReadInterface;
-use Magento\Framework\Filesystem\Directory\WriteFactory;
-use Magento\Framework\Filesystem\Directory\WriteInterface;
+use Magento\Framework\Filesystem\File\WriteFactory as FileWriteFactory;
 
 /**
  * Class PhpStorm generates URN catalog for PhpStorm 9
@@ -23,20 +23,28 @@ class PhpStorm implements FormatInterface
     private $currentDirRead;
 
     /**
-     * @var \Magento\Framework\Filesystem\File\WriteFactory
+     * @var FileWriteFactory
      */
     private $fileWriteFactory;
 
+    /**
+     * @var DomDocumentFactory
+     */
+    private $domDocumentFactory;
+
     /**
      * @param ReadFactory $readFactory
-     * @param \Magento\Framework\Filesystem\File\WriteFactory $fileWriteFactory
+     * @param FileWriteFactory $fileWriteFactory
+     * @param DomDocumentFactory $domDocumentFactory
      */
     public function __construct(
         ReadFactory $readFactory,
-        \Magento\Framework\Filesystem\File\WriteFactory $fileWriteFactory
+        FileWriteFactory $fileWriteFactory,
+        DomDocumentFactory $domDocumentFactory
     ) {
         $this->currentDirRead = $readFactory->create(getcwd());
         $this->fileWriteFactory = $fileWriteFactory;
+        $this->domDocumentFactory = $domDocumentFactory;
     }
 
     /**
@@ -57,26 +65,14 @@ public function generateCatalog(array $dictionary, $configFilePath)
                 \Magento\Framework\Filesystem\DriverPool::FILE,
                 'r'
             );
-            $dom = new \DOMDocument();
-            $dom->loadXML($file->readAll());
+            $dom = $this->domDocumentFactory->create($file->readAll());
             $xpath = new \DOMXPath($dom);
             $nodeList = $xpath->query('/project');
             $projectNode = $nodeList->item(0);
             $file->close();
         } catch (FileSystemException $f) {
             //create file if does not exists
-            $dom = new \DOMDocument();
-            $projectNode = $dom->createElement('project');
-
-            //PhpStorm 9 version for component is "4"
-            $projectNode->setAttribute('version', '4');
-            $dom->appendChild($projectNode);
-            $rootComponentNode = $dom->createElement('component');
-
-            //PhpStorm 9 version for ProjectRootManager is "2"
-            $rootComponentNode->setAttribute('version', '2');
-            $rootComponentNode->setAttribute('name', 'ProjectRootManager');
-            $projectNode->appendChild($rootComponentNode);
+            $dom = $this->domDocumentFactory->create();
         }
 
         $xpath = new \DOMXPath($dom);

app/code/Magento/Developer/Model/XmlCatalog/Format/PhpStorm/DomDocumentFactory.php

@@ -0,0 +1,49 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento\Developer\Model\XmlCatalog\Format\PhpStorm;
+
+use DOMDocument;
+
+class DomDocumentFactory extends \Magento\Framework\DomDocument\DomDocumentFactory
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function create($data = null)
+    {
+        $dom = parent::create($data);
+
+        if (empty($data)) {
+            $this->initializeDocument($dom);
+        }
+
+        return $dom;
+    }
+
+    /**
+     * Initialize document to be used as 'misc.xml'
+     *
+     * @param DOMDocument $document
+     * @return DOMDocument
+     */
+    private function initializeDocument(DOMDocument $document)
+    {
+        $document->xmlVersion = '1.0';
+        $projectNode = $document->createElement('project');
+
+        //PhpStorm 9 version for component is "4"
+        $projectNode->setAttribute('version', '4');
+        $document->appendChild($projectNode);
+        $rootComponentNode = $document->createElement('component');
+
+        //PhpStorm 9 version for ProjectRootManager is "2"
+        $rootComponentNode->setAttribute('version', '2');
+        $rootComponentNode->setAttribute('name', 'ProjectRootManager');
+        $projectNode->appendChild($rootComponentNode);
+
+        return $document;
+    }
+}

lib/internal/Magento/Framework/DomDocument/DomDocumentFactory.php

@@ -3,20 +3,45 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+
 namespace Magento\Framework\DomDocument;
 
+use DOMDocument;
+
 /**
  * DOM document factory
  */
 class DomDocumentFactory
 {
+    /**
+     * @var \Magento\Framework\ObjectManagerInterface
+     */
+    private $objectManager;
+
+    /**
+     * DomDocumentFactory constructor.
+     * @param \Magento\Framework\ObjectManagerInterface $objectManager
+     */
+    public function __construct(\Magento\Framework\ObjectManagerInterface $objectManager)
+    {
+        $this->objectManager = $objectManager;
+    }
+
     /**
      * Create empty DOM document instance.
      *
-     * @return \DOMDocument
+     * @param string $data the data to be loaded into the object
+     *
+     * @return DOMDocument
      */
-    public function create()
+    public function create($data = null)
     {
-        return new \DOMDocument();
+        $dom = $this->objectManager->create(DOMDocument::class);
+
+        if (!empty($data) && is_string($data)) {
+            $dom->loadXML($data);
+        }
+
+        return $dom;
     }
 }

lib/internal/Magento/Framework/Test/Unit/DomDocument/DomDocumentFactoryTest.php

@@ -0,0 +1,95 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+namespace Magento\Framework\Test\Unit\DomDocument;
+
+use DOMDocument;
+use Magento\Framework\DomDocument\DomDocumentFactory;
+use Magento\Framework\ObjectManagerInterface;
+use Magento\Framework\TestFramework\Unit\Helper\ObjectManager as ObjectManagerHelper;
+
+class DomDocumentFactoryTest extends \PHPUnit\Framework\TestCase
+{
+    /**
+     * @var ObjectManagerHelper
+     */
+    private $objectManagerHelper;
+
+    /**
+     * @var ObjectManagerInterface|\PHPUnit_Framework_MockObject_MockObject
+     */
+    private $objectManagerMock;
+
+    /**
+     * @var DOMDocument|\PHPUnit_Framework_MockObject_MockObject
+     */
+    private $domDocumentMock;
+
+    /**
+     * @var DomDocumentFactory
+     */
+    private $domDocumentFactory;
+
+    /**
+     * @var string
+     */
+    private $xmlSample = <<<EOT
+<?xml version="1.0"?>
+<root>
+</root>
+EOT;
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function setUp()
+    {
+        $this->objectManagerHelper = new ObjectManagerHelper($this);
+        $this->objectManagerMock = $this->createMock(ObjectManagerInterface::class);
+        $this->domDocumentMock = $this->createMock(DOMDocument::class);
+        $this->domDocumentFactory = $this->objectManagerHelper->getObject(
+            DomDocumentFactory::class,
+            [
+                'objectManager' => $this->objectManagerMock
+            ]
+        );
+    }
+
+    /**
+     * @dataProvider createDataProvider
+     */
+    public function testCreate($data = null)
+    {
+        $this->objectManagerMock->expects($this->once())
+            ->method('create')
+            ->with(DOMDocument::class)
+            ->willReturn($this->domDocumentMock);
+
+        if (empty($data) || !is_string($data)) {
+            $this->domDocumentMock->expects($this->never())
+                ->method('loadXML');
+        } else {
+            $this->domDocumentMock->expects($this->once())
+                ->method('loadXML')
+                ->with($data)
+                ->willReturn(true);
+        }
+
+        $this->domDocumentFactory->create($data);
+    }
+
+    /**
+     * @return array
+     */
+    public function createDataProvider(): array
+    {
+        return [
+            [null],
+            [''],
+            [$this->xmlSample]
+        ];
+    }
+}