HelpTopicTwigTest.php

<?php

namespace Drupal\Tests\help_topics\Unit;

use Drupal\Core\Cache\Cache;
use Drupal\help_topics\HelpTopicTwig;
use Drupal\Tests\UnitTestCase;

/**
 * Unit test for the HelpTopicTwig class.
 *
 * Note that the toUrl() and toLink() methods are not covered, because they
 * have calls to new Url() and new Link() in them, so they cannot be unit
 * tested.
 *
 * @coversDefaultClass \Drupal\help_topics\HelpTopicTwig
 * @group help_topics
 */
class HelpTopicTwigTest extends UnitTestCase {
    
    /**
     * The help topic instance to test.
     *
     * @var \Drupal\help_topics\HelpTopicTwig
     */
    protected $helpTopic;
    
    /**
     * The plugin information to use for setting up a test topic.
     *
     * @var array
     */
    const PLUGIN_INFORMATION = [
        'id' => 'test.topic',
        'provider' => 'test',
        'label' => 'This is the topic label',
        'top_level' => TRUE,
        'related' => [
            'something',
        ],
        'body' => '<p>This is the topic body</p>',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() {
        $this->helpTopic = new HelpTopicTwig([], self::PLUGIN_INFORMATION['id'], self::PLUGIN_INFORMATION, $this->getTwigMock());
    }
    
    /**
     * @covers ::getBody
     * @covers ::getLabel
     */
    public function testText() {
        $this->assertEquals($this->helpTopic
            ->getBody(), [
            '#markup' => self::PLUGIN_INFORMATION['body'],
        ]);
        $this->assertEquals($this->helpTopic
            ->getLabel(), self::PLUGIN_INFORMATION['label']);
    }
    
    /**
     * @covers ::getProvider
     * @covers ::isTopLevel
     * @covers ::getRelated
     */
    public function testDefinition() {
        $this->assertEquals($this->helpTopic
            ->getProvider(), self::PLUGIN_INFORMATION['provider']);
        $this->assertEquals($this->helpTopic
            ->isTopLevel(), self::PLUGIN_INFORMATION['top_level']);
        $this->assertEquals($this->helpTopic
            ->getRelated(), self::PLUGIN_INFORMATION['related']);
    }
    
    /**
     * @covers ::getCacheContexts
     * @covers ::getCacheTags
     * @covers ::getCacheMaxAge
     */
    public function testCacheInfo() {
        $this->assertEquals($this->helpTopic
            ->getCacheContexts(), []);
        $this->assertEquals($this->helpTopic
            ->getCacheTags(), [
            'core.extension',
        ]);
        $this->assertEquals($this->helpTopic
            ->getCacheMaxAge(), Cache::PERMANENT);
    }
    
    /**
     * Creates a mock Twig loader class for the test.
     */
    protected function getTwigMock() {
        $twig = $this->getMockBuilder('Drupal\\Core\\Template\\TwigEnvironment')
            ->disableOriginalConstructor()
            ->getMock();
        $twig->method('load')
            ->willReturn(new FakeTemplateWrapper(self::PLUGIN_INFORMATION['body']));
        return $twig;
    }

}

/**
 * Defines a fake template class to mock \Twig_TemplateWrapper.
 *
 * We cannot use getMockBuilder() for this, because the Twig TemplateWrapper
 * class is declared "final" and cannot be mocked.
 */
class FakeTemplateWrapper {
    
    /**
     * Body text to return from the render() method.
     *
     * @var string
     */
    protected $body;
    
    /**
     * Constructor.
     *
     * @param string $body
     *   Body text to return from the render() method.
     */
    public function __construct($body) {
        $this->body = $body;
    }
    
    /**
     * Mocks the \Twig_TemplateWrapper render() method.
     *
     * @param array $context
     *   (optional) Render context.
     */
    public function render(array $context = []) {
        return $this->body;
    }

}