class HelpTopicTwigLoaderTest

class HelpTopicTwigLoaderTest extends UnitTestCase {
    
    /**
     * The help topic loader instance to test.
     *
     * @var \Drupal\help_topics\HelpTopicTwigLoader
     */
    protected $helpLoader;
    
    /**
     * The virtual directories to use in testing.
     *
     * @var array
     */
    protected $directories;
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() {
        $this->setUpVfs();
        $this->helpLoader = new HelpTopicTwigLoader('\\fake\\root\\path', $this->getHandlerMock('module'), $this->getHandlerMock('theme'));
    }
    
    /**
     * @covers ::__construct
     */
    public function testConstructor() {
        // Verify that the module/theme directories were added in the constructor,
        // and non-existent directories were omitted.
        $paths = $this->helpLoader
            ->getPaths(HelpTopicTwigLoader::MAIN_NAMESPACE);
        $this->assertCount(2, $paths);
        $this->assertContains($this->directories['module']['test'] . '/help_topics', $paths);
        $this->assertContains($this->directories['theme']['test'] . '/help_topics', $paths);
    }
    
    /**
     * @covers ::getSourceContext
     */
    public function testGetSourceContext() {
        $source = $this->helpLoader
            ->getSourceContext('@' . HelpTopicTwigLoader::MAIN_NAMESPACE . '/test.topic.html.twig');
        $this->assertEquals('{% line 4 %}<h2>Test</h2>', $source->getCode());
    }
    
    /**
     * @covers ::getSourceContext
     */
    public function testGetSourceContextException() {
        $this->expectException(LoaderError::class);
        $this->expectExceptionMessage("Malformed YAML in help topic \"vfs://root/modules/test/help_topics/test.invalid_yaml.html.twig\":");
        $source = $this->helpLoader
            ->getSourceContext('@' . HelpTopicTwigLoader::MAIN_NAMESPACE . '/test.invalid_yaml.html.twig');
    }
    
    /**
     * Creates a mock module or theme handler class for the test.
     *
     * @param string $type
     *   Type of handler to return: 'module' or 'theme'.
     *
     * @return \PHPUnit\Framework\MockObject\MockObject
     *   The mock of module or theme handler.
     */
    protected function getHandlerMock($type) {
        if ($type == 'module') {
            $class = 'Drupal\\Core\\Extension\\ModuleHandlerInterface';
            $method = 'getModuleDirectories';
        }
        else {
            $class = 'Drupal\\Core\\Extension\\ThemeHandlerInterface';
            $method = 'getThemeDirectories';
        }
        $handler = $this->getMockBuilder($class)
            ->disableOriginalConstructor()
            ->getMock();
        $handler->method($method)
            ->willReturn($this->directories[$type]);
        return $handler;
    }
    
    /**
     * Sets up the virtual file system.
     */
    protected function setUpVfs() {
        $content = <<<EOF
---
label: Test
---
<h2>Test</h2>
EOF;
        $invalid_content = <<<EOF
---
foo : [bar}
---
<h2>Test</h2>
EOF;
        $help_topics_dir = [
            'help_topics' => [
                'test.topic.html.twig' => $content,
                'test.invalid_yaml.html.twig' => $invalid_content,
            ],
        ];
        vfsStream::setup('root');
        vfsStream::create([
            'modules' => [
                'test' => $help_topics_dir,
            ],
            'themes' => [
                'test' => $help_topics_dir,
            ],
        ]);
        $this->directories = [
            'root' => vfsStream::url('root'),
            'module' => [
                'test' => vfsStream::url('root/modules/test'),
                'not_a_dir' => vfsStream::url('root/modules/not_a_dir'),
            ],
            'theme' => [
                'test' => vfsStream::url('root/themes/test'),
                'not_a_dir' => vfsStream::url('root/themes/not_a_dir'),
            ],
        ];
    }

}