Fix #24656: add tests for layout XML validation

Author: korostii

dev/tests/integration/testsuite/Magento/Test/Integrity/Modular/LayoutConfigFilesTest.php

@@ -0,0 +1,54 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento\Test\Integrity\Modular;
+
+class LayoutConfigFilesTest extends \PHPUnit\Framework\TestCase
+{
+    /**
+     * Path to schema file
+     *
+     * @var string
+     */
+    protected $schemaFile;
+
+    protected function setUp()
+    {
+        $urnResolver = new \Magento\Framework\Config\Dom\UrnResolver();
+        $this->schemaFile = $urnResolver->getRealPath('urn:magento:framework:View/Layout/etc/elements.xsd');
+    }
+
+    /**
+     * Test a valid layout XML file
+     */
+    public function testValidLayoutXmlFile()
+    {
+        $validationStateMock = $this->createMock(\Magento\Framework\Config\ValidationStateInterface::class);
+        $validationStateMock->method('isValidationRequired')->willReturn(true);
+        $domConfig = new \Magento\Framework\Config\Dom(
+            '<referenceBlock name="product.info.something" group="column_left"></referenceBlock>',
+            $validationStateMock
+        );
+        $result = $domConfig->validate($this->schemaFile, $errors);
+        $this->assertTrue($result);
+        $this->assertEmpty($errors);
+    }
+
+    /**
+     * Test a layout XML file having an invalid tag element
+     */
+    public function testBrokenLayoutXmlFile()
+    {
+        $validationStateMock = $this->createMock(\Magento\Framework\Config\ValidationStateInterface::class);
+        $validationStateMock->method('isValidationRequired')->willReturn(true);
+        $domConfig = new \Magento\Framework\Config\Dom(
+            '<invalidElement name="some.name"></invalidElement>',
+            $validationStateMock
+        );
+        $result = $domConfig->validate($this->schemaFile, $errors);
+        $this->assertFalse($result);
+        $this->assertNotEmpty($errors);
+    }
+}