Add PHPUnit tests for VectorComponentLink

Adds tests for VectorComponentLink in Vector skin, ensuring:
- Initialization with parameters.
- Generation of html-attributes string with title and aria-label.
- Consistency in link attributes for accessibility and UX.

Change-Id: I80b8a84d1d10bc7274ba5267910206d7f6e68534

tests/phpunit/unit/components/VectorComponentLinkTest.php

@@ -0,0 +1,76 @@
+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @since 1.42
+ */
+
+namespace MediaWiki\Skins\Vector\Tests\Unit\Components;
+
+use MediaWiki\Skins\Vector\Components\VectorComponentLink;
+use MediaWikiUnitTestCase;
+use Message;
+use MessageLocalizer;
+
+/**
+ * @group Vector
+ * @group Components
+ * @coversDefaultClass \MediaWiki\Skins\Vector\Components\VectorComponentLink
+ */
+class VectorComponentLinkTest extends MediaWikiUnitTestCase {
+
+	/**
+	 * @covers ::getTemplateData
+	 */
+	public function testGetTemplateData() {
+		$href = '/mock-link';
+		$text = 'Mock Text';
+		$icon = 'mock-icon';
+		$accessKeyHint = 'sample-accesskey';
+
+		$localizer = $this->createMock( MessageLocalizer::class );
+		// Adjusting mock to prevent calling the service container.
+		$localizer->method( 'msg' )
+			->willReturnCallback( function ( $key ) use ( $accessKeyHint ) {
+				// Directly create Message object without accessing real message texts
+				// to avoid 'Premature access to service container' error.
+				return $this->createConfiguredMock( Message::class, [
+					'exists' => true,
+					'text' => $key === $accessKeyHint . '-label' ? 'Mock aria label' : $key,
+					'__toString' => 'Mock aria label',
+				] );
+			} );
+
+		// Create the component
+		$linkComponent = new VectorComponentLink( $href, $text, $icon, $localizer, $accessKeyHint );
+		$actual = $linkComponent->getTemplateData();
+
+		// Assert the expected values
+		$this->assertEquals( $icon, $actual['icon'] );
+		$this->assertEquals( $text, $actual['text'] );
+		$this->assertEquals( $href, $actual['href'] );
+
+		// New assertions for HTML attributes
+		$expectedTitle = "tooltip-sample-accesskeyword-separatorbrackets";
+		$expectedAriaLabel = "Mock aria label";
+		$attributesString = $actual['html-attributes'];
+
+		// Assert that the expected attributes are present in the string
+		$this->assertStringContainsString( 'title="' . $expectedTitle . '"', $attributesString );
+		$this->assertStringContainsString( 'aria-label="' . $expectedAriaLabel . '"', $attributesString );
+	}
+}