Unit test added for page service class and code review changes

Author: Mohamed-Asar

app/code/Magento/Cms/Model/Page/Service/PageService.php

@@ -23,9 +23,9 @@ class PageService
      * @param CustomLayoutManagerInterface $customLayoutManager
      */
     public function __construct(
-        private PageRepositoryInterface $pageRepository,
-        private PageFactory $pageFactory,
-        private CustomLayoutManagerInterface $customLayoutManager,
+        private readonly PageRepositoryInterface $pageRepository,
+        private readonly PageFactory $pageFactory,
+        private readonly CustomLayoutManagerInterface $customLayoutManager,
     ) {
     }
 

app/code/Magento/Cms/Test/Unit/Model/Page/Service/PageServiceTest.php

@@ -0,0 +1,182 @@
+<?php
+/**
+ * Copyright 2025 Adobe
+ * All Rights Reserved.
+ */
+declare(strict_types=1);
+
+namespace Magento\Cms\Test\Unit\Model\Page\Service;
+
+use Magento\Cms\Api\Data\PageInterface;
+use Magento\Cms\Api\PageRepositoryInterface;
+use Magento\Cms\Model\Page\CustomLayoutManagerInterface;
+use Magento\Cms\Model\Page\Service\PageService;
+use Magento\Cms\Model\PageFactory;
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Framework\Exception\NoSuchEntityException;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Unit tests for PageService
+ */
+class PageServiceTest extends TestCase
+{
+    /**
+     * @var PageRepositoryInterface|MockObject
+     */
+    private $pageRepositoryMock;
+
+    /**
+     * @var PageFactory|MockObject
+     */
+    private $pageFactoryMock;
+
+    /**
+     * @var CustomLayoutManagerInterface|MockObject
+     */
+    private $customLayoutManagerMock;
+
+    /**
+     * @var PageService
+     */
+    private $pageService;
+
+    /**
+     * @var PageInterface|MockObject
+     */
+    private $pageMock;
+
+    /**
+     * Set up test environment
+     */
+    protected function setUp(): void
+    {
+        $this->pageRepositoryMock = $this->createMock(PageRepositoryInterface::class);
+        $this->pageFactoryMock = $this->createMock(PageFactory::class);
+        $this->customLayoutManagerMock = $this->createMock(CustomLayoutManagerInterface::class);
+        $this->pageMock = $this->createMock(PageInterface::class);
+
+        $this->pageService = new PageService(
+            $this->pageRepositoryMock,
+            $this->pageFactoryMock,
+            $this->customLayoutManagerMock
+        );
+    }
+
+    /**
+     * Test getPageById returns existing page when page exists
+     */
+    public function testGetPageByIdReturnsExistingPage(): void
+    {
+        $pageId = 1;
+
+        $this->pageRepositoryMock->expects($this->once())
+            ->method('getById')
+            ->with($pageId)
+            ->willReturn($this->pageMock);
+
+        $this->pageFactoryMock->expects($this->never())
+            ->method('create');
+
+        $result = $this->pageService->getPageById($pageId);
+
+        $this->assertSame($this->pageMock, $result);
+    }
+
+    /**
+     * Test getPageById returns new page instance when page doesn't exist
+     */
+    public function testGetPageByIdReturnsNewPageWhenNotExists(): void
+    {
+        $pageId = 999;
+        $newPageMock = $this->createMock(PageInterface::class);
+
+        $this->pageRepositoryMock->expects($this->once())
+            ->method('getById')
+            ->with($pageId)
+            ->willThrowException(new NoSuchEntityException(__('Page not found')));
+
+        $this->pageFactoryMock->expects($this->once())
+            ->method('create')
+            ->willReturn($newPageMock);
+
+        $result = $this->pageService->getPageById($pageId);
+
+        $this->assertSame($newPageMock, $result);
+    }
+
+    /**
+     * Test getPageById handles LocalizedException and returns new page
+     */
+    public function testGetPageByIdHandlesLocalizedException(): void
+    {
+        $pageId = 1;
+        $newPageMock = $this->createMock(PageInterface::class);
+
+        $this->pageRepositoryMock->expects($this->once())
+            ->method('getById')
+            ->with($pageId)
+            ->willThrowException(new LocalizedException(__('Some localized error')));
+
+        $this->pageFactoryMock->expects($this->once())
+            ->method('create')
+            ->willReturn($newPageMock);
+
+        $result = $this->pageService->getPageById($pageId);
+
+        $this->assertSame($newPageMock, $result);
+    }
+
+    /**
+     * Test createPageFactory returns new page instance
+     */
+    public function testCreatePageFactory(): void
+    {
+        $newPageMock = $this->createMock(PageInterface::class);
+
+        $this->pageFactoryMock->expects($this->once())
+            ->method('create')
+            ->willReturn($newPageMock);
+
+        $result = $this->pageService->createPageFactory();
+
+        $this->assertSame($newPageMock, $result);
+    }
+
+    /**
+     * Test fetchAvailableCustomLayouts returns available layouts
+     */
+    public function testFetchAvailableCustomLayouts(): void
+    {
+        $expectedLayouts = [
+            'layout1.xml',
+            'layout2.xml',
+            'custom_layout.xml'
+        ];
+
+        $this->customLayoutManagerMock->expects($this->once())
+            ->method('fetchAvailableFiles')
+            ->with($this->pageMock)
+            ->willReturn($expectedLayouts);
+
+        $result = $this->pageService->fetchAvailableCustomLayouts($this->pageMock);
+
+        $this->assertSame($expectedLayouts, $result);
+    }
+
+    /**
+     * Test fetchAvailableCustomLayouts returns empty array when no layouts available
+     */
+    public function testFetchAvailableCustomLayoutsReturnsEmptyArray(): void
+    {
+        $this->customLayoutManagerMock->expects($this->once())
+            ->method('fetchAvailableFiles')
+            ->with($this->pageMock)
+            ->willReturn([]);
+
+        $result = $this->pageService->fetchAvailableCustomLayouts($this->pageMock);
+
+        $this->assertSame([], $result);
+    }
+}