class FunctionsTest

class FunctionsTest extends KernelTestBase {
    
    /**
     * Modules to enable.
     *
     * @var array
     */
    public static $modules = [
        'router_test',
        'system',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() {
        parent::setUp();
        // Enable the Classy theme.
        $this->container
            ->get('theme_installer')
            ->install([
            'classy',
        ]);
        $this->config('system.theme')
            ->set('default', 'classy')
            ->save();
    }
    
    /**
     * Tests item-list.html.twig.
     */
    public function testItemList() {
        // Verify that empty items produce no output.
        $variables = [];
        $expected = '';
        $this->assertThemeOutput('item_list', $variables, $expected, 'Empty %callback generates no output.');
        // Verify that empty items with title produce no output.
        $variables = [];
        $variables['title'] = 'Some title';
        $expected = '';
        $this->assertThemeOutput('item_list', $variables, $expected, 'Empty %callback with title generates no output.');
        // Verify that empty items produce the empty string.
        $variables = [];
        $variables['empty'] = 'No items found.';
        $expected = '<div class="item-list">No items found.</div>';
        $this->assertThemeOutput('item_list', $variables, $expected, 'Empty %callback generates empty string.');
        // Verify that empty items produce the empty string with title.
        $variables = [];
        $variables['title'] = 'Some title';
        $variables['empty'] = 'No items found.';
        $expected = '<div class="item-list"><h3>Some title</h3>No items found.</div>';
        $this->assertThemeOutput('item_list', $variables, $expected, 'Empty %callback generates empty string with title.');
        // Verify that title set to 0 is output.
        $variables = [];
        $variables['title'] = 0;
        $variables['empty'] = 'No items found.';
        $expected = '<div class="item-list"><h3>0</h3>No items found.</div>';
        $this->assertThemeOutput('item_list', $variables, $expected, '%callback with title set to 0 generates a title.');
        // Verify that title set to a render array is output.
        $variables = [];
        $variables['title'] = [
            '#markup' => '<span>Render array</span>',
        ];
        $variables['empty'] = 'No items found.';
        $expected = '<div class="item-list"><h3><span>Render array</span></h3>No items found.</div>';
        $this->assertThemeOutput('item_list', $variables, $expected, '%callback with title set to a render array generates a title.');
        // Verify that empty text is not displayed when there are list items.
        $variables = [];
        $variables['title'] = 'Some title';
        $variables['empty'] = 'No items found.';
        $variables['items'] = [
            'Un',
            'Deux',
            'Trois',
        ];
        $expected = '<div class="item-list"><h3>Some title</h3><ul><li>Un</li><li>Deux</li><li>Trois</li></ul></div>';
        $this->assertThemeOutput('item_list', $variables, $expected, '%callback does not print empty text when there are list items.');
        // Verify nested item lists.
        $variables = [];
        $variables['title'] = 'Some title';
        $variables['attributes'] = [
            'id' => 'parentlist',
        ];
        $variables['items'] = [
            // A plain string value forms an own item.
'a',
            // Items can be fully-fledged render arrays with their own attributes.
[
                '#wrapper_attributes' => [
                    'id' => 'item-id-b',
                ],
                '#markup' => 'b',
                'childlist' => [
                    '#theme' => 'item_list',
                    '#attributes' => [
                        'id' => 'blist',
                    ],
                    '#list_type' => 'ol',
                    '#items' => [
                        'ba',
                        [
                            '#markup' => 'bb',
                            '#wrapper_attributes' => [
                                'class' => [
                                    'item-class-bb',
                                ],
                            ],
                        ],
                    ],
                ],
            ],
            // However, items can also be child #items.
[
                '#markup' => 'c',
                'childlist' => [
                    '#attributes' => [
                        'id' => 'clist',
                    ],
                    'ca',
                    [
                        '#markup' => 'cb',
                        '#wrapper_attributes' => [
                            'class' => [
                                'item-class-cb',
                            ],
                        ],
                        'children' => [
                            'cba',
                            'cbb',
                        ],
                    ],
                    'cc',
                ],
            ],
            // Use #markup to be able to specify #wrapper_attributes.
[
                '#markup' => 'd',
                '#wrapper_attributes' => [
                    'id' => 'item-id-d',
                ],
            ],
            // An empty item with attributes.
[
                '#wrapper_attributes' => [
                    'id' => 'item-id-e',
                ],
            ],
            // Lastly, another plain string item.
'f',
        ];
        $inner_b = '<div class="item-list"><ol id="blist">';
        $inner_b .= '<li>ba</li>';
        $inner_b .= '<li class="item-class-bb">bb</li>';
        $inner_b .= '</ol></div>';
        $inner_cb = '<div class="item-list"><ul>';
        $inner_cb .= '<li>cba</li>';
        $inner_cb .= '<li>cbb</li>';
        $inner_cb .= '</ul></div>';
        $inner_c = '<div class="item-list"><ul id="clist">';
        $inner_c .= '<li>ca</li>';
        $inner_c .= '<li class="item-class-cb">cb' . $inner_cb . '</li>';
        $inner_c .= '<li>cc</li>';
        $inner_c .= '</ul></div>';
        $expected = '<div class="item-list">';
        $expected .= '<h3>Some title</h3>';
        $expected .= '<ul id="parentlist">';
        $expected .= '<li>a</li>';
        $expected .= '<li id="item-id-b">b' . $inner_b . '</li>';
        $expected .= '<li>c' . $inner_c . '</li>';
        $expected .= '<li id="item-id-d">d</li>';
        $expected .= '<li id="item-id-e"></li>';
        $expected .= '<li>f</li>';
        $expected .= '</ul></div>';
        $this->assertThemeOutput('item_list', $variables, $expected);
    }
    
    /**
     * Tests links.html.twig.
     */
    public function testLinks() {
        // Turn off the query for the
        // \Drupal\Core\Utility\LinkGeneratorInterface::generate() method to compare
        // the active link correctly.
        $original_query = \Drupal::request()->query
            ->all();
        \Drupal::request()->query
            ->replace([]);
        // Verify that empty variables produce no output.
        $variables = [];
        $expected = '';
        $this->assertThemeOutput('links', $variables, $expected, 'Empty %callback generates no output.');
        $variables = [];
        $variables['heading'] = 'Some title';
        $expected = '';
        $this->assertThemeOutput('links', $variables, $expected, 'Empty %callback with heading generates no output.');
        // Verify that a list of links is properly rendered.
        $variables = [];
        $variables['attributes'] = [
            'id' => 'somelinks',
        ];
        $variables['links'] = [
            'a link' => [
                'title' => 'A <link>',
                'url' => Url::fromUri('base:a/link'),
            ],
            'plain text' => [
                'title' => 'Plain "text"',
            ],
            'html text' => [
                'title' => new FormattableMarkup('<span class="unescaped">@text</span>', [
                    '@text' => 'potentially unsafe text that <should> be escaped',
                ]),
            ],
            'front page' => [
                'title' => 'Front page',
                'url' => Url::fromRoute('<front>'),
            ],
            'router-test' => [
                'title' => 'Test route',
                'url' => Url::fromRoute('router_test.1'),
            ],
            'query-test' => [
                'title' => 'Query test route',
                'url' => Url::fromRoute('router_test.1'),
                'query' => [
                    'key' => 'value',
                ],
            ],
        ];
        $expected_links = '';
        $expected_links .= '<ul id="somelinks">';
        $expected_links .= '<li class="a-link"><a href="' . Url::fromUri('base:a/link')->toString() . '">' . Html::escape('A <link>') . '</a></li>';
        $expected_links .= '<li class="plain-text">' . Html::escape('Plain "text"') . '</li>';
        $expected_links .= '<li class="html-text"><span class="unescaped">' . Html::escape('potentially unsafe text that <should> be escaped') . '</span></li>';
        $expected_links .= '<li class="front-page"><a href="' . Url::fromRoute('<front>')->toString() . '">' . Html::escape('Front page') . '</a></li>';
        $expected_links .= '<li class="router-test"><a href="' . \Drupal::urlGenerator()->generate('router_test.1') . '">' . Html::escape('Test route') . '</a></li>';
        $query = [
            'key' => 'value',
        ];
        $expected_links .= '<li class="query-test"><a href="' . \Drupal::urlGenerator()->generate('router_test.1', $query) . '">' . Html::escape('Query test route') . '</a></li>';
        $expected_links .= '</ul>';
        // Verify that passing a string as heading works.
        $variables['heading'] = 'Links heading';
        $expected_heading = '<h2>Links heading</h2>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
        // Restore the original request's query.
        \Drupal::request()->query
            ->replace($original_query);
        // Verify that passing an array as heading works (core support).
        $variables['heading'] = [
            'text' => 'Links heading',
            'level' => 'h3',
            'attributes' => [
                'class' => [
                    'heading',
                ],
            ],
        ];
        $expected_heading = '<h3 class="heading">Links heading</h3>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
        // Verify that passing attributes for the heading works.
        $variables['heading'] = [
            'text' => 'Links heading',
            'level' => 'h3',
            'attributes' => [
                'id' => 'heading',
            ],
        ];
        $expected_heading = '<h3 id="heading">Links heading</h3>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
        // Verify that passing attributes for the links work.
        $variables['links']['plain text']['attributes'] = [
            'class' => [
                'a/class',
            ],
        ];
        $expected_links = '';
        $expected_links .= '<ul id="somelinks">';
        $expected_links .= '<li class="a-link"><a href="' . Url::fromUri('base:a/link')->toString() . '">' . Html::escape('A <link>') . '</a></li>';
        $expected_links .= '<li class="plain-text"><span class="a/class">' . Html::escape('Plain "text"') . '</span></li>';
        $expected_links .= '<li class="html-text"><span class="unescaped">' . Html::escape('potentially unsafe text that <should> be escaped') . '</span></li>';
        $expected_links .= '<li class="front-page"><a href="' . Url::fromRoute('<front>')->toString() . '">' . Html::escape('Front page') . '</a></li>';
        $expected_links .= '<li class="router-test"><a href="' . \Drupal::urlGenerator()->generate('router_test.1') . '">' . Html::escape('Test route') . '</a></li>';
        $query = [
            'key' => 'value',
        ];
        $expected_links .= '<li class="query-test"><a href="' . \Drupal::urlGenerator()->generate('router_test.1', $query) . '">' . Html::escape('Query test route') . '</a></li>';
        $expected_links .= '</ul>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
        // Verify the data- attributes for setting the "active" class on links.
        \Drupal::currentUser()->setAccount(new UserSession([
            'uid' => 1,
        ]));
        $variables['set_active_class'] = TRUE;
        $expected_links = '';
        $expected_links .= '<ul id="somelinks">';
        $expected_links .= '<li class="a-link"><a href="' . Url::fromUri('base:a/link')->toString() . '">' . Html::escape('A <link>') . '</a></li>';
        $expected_links .= '<li class="plain-text"><span class="a/class">' . Html::escape('Plain "text"') . '</span></li>';
        $expected_links .= '<li class="html-text"><span class="unescaped">' . Html::escape('potentially unsafe text that <should> be escaped') . '</span></li>';
        $expected_links .= '<li data-drupal-link-system-path="&lt;front&gt;" class="front-page"><a href="' . Url::fromRoute('<front>')->toString() . '" data-drupal-link-system-path="&lt;front&gt;">' . Html::escape('Front page') . '</a></li>';
        $expected_links .= '<li data-drupal-link-system-path="router_test/test1" class="router-test"><a href="' . \Drupal::urlGenerator()->generate('router_test.1') . '" data-drupal-link-system-path="router_test/test1">' . Html::escape('Test route') . '</a></li>';
        $query = [
            'key' => 'value',
        ];
        $encoded_query = Html::escape(Json::encode($query));
        $expected_links .= '<li data-drupal-link-query="' . $encoded_query . '" data-drupal-link-system-path="router_test/test1" class="query-test"><a href="' . \Drupal::urlGenerator()->generate('router_test.1', $query) . '" data-drupal-link-query="' . $encoded_query . '" data-drupal-link-system-path="router_test/test1">' . Html::escape('Query test route') . '</a></li>';
        $expected_links .= '</ul>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
    }
    
    /**
     * Tests links.html.twig using links with indexed keys.
     */
    public function testIndexedKeyedLinks() {
        // Turn off the query for the
        // \Drupal\Core\Utility\LinkGeneratorInterface::generate() method to compare
        // the active link correctly.
        $original_query = \Drupal::request()->query
            ->all();
        \Drupal::request()->query
            ->replace([]);
        // Verify that empty variables produce no output.
        $variables = [];
        $expected = '';
        $this->assertThemeOutput('links', $variables, $expected, 'Empty %callback generates no output.');
        $variables = [];
        $variables['heading'] = 'Some title';
        $expected = '';
        $this->assertThemeOutput('links', $variables, $expected, 'Empty %callback with heading generates no output.');
        // Verify that a list of links is properly rendered.
        $variables = [];
        $variables['attributes'] = [
            'id' => 'somelinks',
        ];
        $variables['links'] = [
            [
                'title' => 'A <link>',
                'url' => Url::fromUri('base:a/link'),
            ],
            [
                'title' => 'Plain "text"',
            ],
            [
                'title' => new FormattableMarkup('<span class="unescaped">@text</span>', [
                    '@text' => 'potentially unsafe text that <should> be escaped',
                ]),
            ],
            [
                'title' => 'Front page',
                'url' => Url::fromRoute('<front>'),
            ],
            [
                'title' => 'Test route',
                'url' => Url::fromRoute('router_test.1'),
            ],
            [
                'title' => 'Query test route',
                'url' => Url::fromRoute('router_test.1'),
                'query' => [
                    'key' => 'value',
                ],
            ],
        ];
        $expected_links = '';
        $expected_links .= '<ul id="somelinks">';
        $expected_links .= '<li><a href="' . Url::fromUri('base:a/link')->toString() . '">' . Html::escape('A <link>') . '</a></li>';
        $expected_links .= '<li>' . Html::escape('Plain "text"') . '</li>';
        $expected_links .= '<li><span class="unescaped">' . Html::escape('potentially unsafe text that <should> be escaped') . '</span></li>';
        $expected_links .= '<li><a href="' . Url::fromRoute('<front>')->toString() . '">' . Html::escape('Front page') . '</a></li>';
        $expected_links .= '<li><a href="' . \Drupal::urlGenerator()->generate('router_test.1') . '">' . Html::escape('Test route') . '</a></li>';
        $query = [
            'key' => 'value',
        ];
        $expected_links .= '<li><a href="' . \Drupal::urlGenerator()->generate('router_test.1', $query) . '">' . Html::escape('Query test route') . '</a></li>';
        $expected_links .= '</ul>';
        // Verify that passing a string as heading works.
        $variables['heading'] = 'Links heading';
        $expected_heading = '<h2>Links heading</h2>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
        // Restore the original request's query.
        \Drupal::request()->query
            ->replace($original_query);
        // Verify that passing an array as heading works (core support).
        $variables['heading'] = [
            'text' => 'Links heading',
            'level' => 'h3',
            'attributes' => [
                'class' => [
                    'heading',
                ],
            ],
        ];
        $expected_heading = '<h3 class="heading">Links heading</h3>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
        // Verify that passing attributes for the heading works.
        $variables['heading'] = [
            'text' => 'Links heading',
            'level' => 'h3',
            'attributes' => [
                'id' => 'heading',
            ],
        ];
        $expected_heading = '<h3 id="heading">Links heading</h3>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
        // Verify that passing attributes for the links work.
        $variables['links'][1]['attributes'] = [
            'class' => [
                'a/class',
            ],
        ];
        $expected_links = '';
        $expected_links .= '<ul id="somelinks">';
        $expected_links .= '<li><a href="' . Url::fromUri('base:a/link')->toString() . '">' . Html::escape('A <link>') . '</a></li>';
        $expected_links .= '<li><span class="a/class">' . Html::escape('Plain "text"') . '</span></li>';
        $expected_links .= '<li><span class="unescaped">' . Html::escape('potentially unsafe text that <should> be escaped') . '</span></li>';
        $expected_links .= '<li><a href="' . Url::fromRoute('<front>')->toString() . '">' . Html::escape('Front page') . '</a></li>';
        $expected_links .= '<li><a href="' . \Drupal::urlGenerator()->generate('router_test.1') . '">' . Html::escape('Test route') . '</a></li>';
        $query = [
            'key' => 'value',
        ];
        $expected_links .= '<li><a href="' . \Drupal::urlGenerator()->generate('router_test.1', $query) . '">' . Html::escape('Query test route') . '</a></li>';
        $expected_links .= '</ul>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
        // Verify the data- attributes for setting the "active" class on links.
        \Drupal::currentUser()->setAccount(new UserSession([
            'uid' => 1,
        ]));
        $variables['set_active_class'] = TRUE;
        $expected_links = '';
        $expected_links .= '<ul id="somelinks">';
        $expected_links .= '<li><a href="' . Url::fromUri('base:a/link')->toString() . '">' . Html::escape('A <link>') . '</a></li>';
        $expected_links .= '<li><span class="a/class">' . Html::escape('Plain "text"') . '</span></li>';
        $expected_links .= '<li><span class="unescaped">' . Html::escape('potentially unsafe text that <should> be escaped') . '</span></li>';
        $expected_links .= '<li data-drupal-link-system-path="&lt;front&gt;"><a href="' . Url::fromRoute('<front>')->toString() . '" data-drupal-link-system-path="&lt;front&gt;">' . Html::escape('Front page') . '</a></li>';
        $expected_links .= '<li data-drupal-link-system-path="router_test/test1"><a href="' . \Drupal::urlGenerator()->generate('router_test.1') . '" data-drupal-link-system-path="router_test/test1">' . Html::escape('Test route') . '</a></li>';
        $query = [
            'key' => 'value',
        ];
        $encoded_query = Html::escape(Json::encode($query));
        $expected_links .= '<li data-drupal-link-query="' . $encoded_query . '" data-drupal-link-system-path="router_test/test1"><a href="' . \Drupal::urlGenerator()->generate('router_test.1', $query) . '" data-drupal-link-query="' . $encoded_query . '" data-drupal-link-system-path="router_test/test1">' . Html::escape('Query test route') . '</a></li>';
        $expected_links .= '</ul>';
        $expected = $expected_heading . $expected_links;
        $this->assertThemeOutput('links', $variables, $expected);
    }
    
    /**
     * Test the use of Link::preRenderLinks() on a nested array of links.
     *
     * @see \Drupal\Core\Render\Element\Link::preRenderLinks()
     */
    public function testDrupalPreRenderLinks() {
        // Define the base array to be rendered, containing a variety of different
        // kinds of links.
        $base_array = [
            '#theme' => 'links',
            '#pre_render' => [
                [
                    Link::class,
                    'preRenderLinks',
                ],
            ],
            '#links' => [
                'parent_link' => [
                    'title' => 'Parent link original',
                    'url' => Url::fromRoute('router_test.1'),
                ],
            ],
            'first_child' => [
                '#theme' => 'links',
                '#links' => [
                    // This should be rendered if 'first_child' is rendered separately,
                    // but ignored if the parent is being rendered (since it duplicates
                    // one of the parent's links).
'parent_link' => [
                        'title' => 'Parent link copy',
                        'url' => Url::fromRoute('router_test.6'),
                    ],
                    // This should always be rendered.
'first_child_link' => [
                        'title' => 'First child link',
                        'url' => Url::fromRoute('router_test.7'),
                    ],
                ],
            ],
            // This should always be rendered as part of the parent.
'second_child' => [
                '#theme' => 'links',
                '#links' => [
                    'second_child_link' => [
                        'title' => 'Second child link',
                        'url' => Url::fromRoute('router_test.8'),
                    ],
                ],
            ],
            // This should never be rendered, since the user does not have access to
            // it.
'third_child' => [
                '#theme' => 'links',
                '#links' => [
                    'third_child_link' => [
                        'title' => 'Third child link',
                        'url' => Url::fromRoute('router_test.9'),
                    ],
                ],
                '#access' => FALSE,
            ],
        ];
        // Start with a fresh copy of the base array, and try rendering the entire
        // thing. We expect a single <ul> with appropriate links contained within
        // it.
        $render_array = $base_array;
        $html = \Drupal::service('renderer')->renderRoot($render_array);
        $dom = new \DOMDocument();
        $dom->loadHTML($html);
        $this->assertEqual($dom->getElementsByTagName('ul')->length, 1, 'One "ul" tag found in the rendered HTML.');
        $list_elements = $dom->getElementsByTagName('li');
        $this->assertEqual($list_elements->length, 3, 'Three "li" tags found in the rendered HTML.');
        $this->assertEqual($list_elements->item(0)->nodeValue, 'Parent link original', 'First expected link found.');
        $this->assertEqual($list_elements->item(1)->nodeValue, 'First child link', 'Second expected link found.');
        $this->assertEqual($list_elements->item(2)->nodeValue, 'Second child link', 'Third expected link found.');
        $this->assertStringNotContainsString('Parent link copy', $html, '"Parent link copy" link not found.');
        $this->assertStringNotContainsString('Third child link', $html, '"Third child link" link not found.');
        // Now render 'first_child', followed by the rest of the links, and make
        // sure we get two separate <ul>'s with the appropriate links contained
        // within each.
        $render_array = $base_array;
        $child_html = \Drupal::service('renderer')->renderRoot($render_array['first_child']);
        $parent_html = \Drupal::service('renderer')->renderRoot($render_array);
        // First check the child HTML.
        $dom = new \DOMDocument();
        $dom->loadHTML($child_html);
        $this->assertEqual($dom->getElementsByTagName('ul')->length, 1, 'One "ul" tag found in the rendered child HTML.');
        $list_elements = $dom->getElementsByTagName('li');
        $this->assertEqual($list_elements->length, 2, 'Two "li" tags found in the rendered child HTML.');
        $this->assertEqual($list_elements->item(0)->nodeValue, 'Parent link copy', 'First expected link found.');
        $this->assertEqual($list_elements->item(1)->nodeValue, 'First child link', 'Second expected link found.');
        // Then check the parent HTML.
        $dom = new \DOMDocument();
        $dom->loadHTML($parent_html);
        $this->assertEqual($dom->getElementsByTagName('ul')->length, 1, 'One "ul" tag found in the rendered parent HTML.');
        $list_elements = $dom->getElementsByTagName('li');
        $this->assertEqual($list_elements->length, 2, 'Two "li" tags found in the rendered parent HTML.');
        $this->assertEqual($list_elements->item(0)->nodeValue, 'Parent link original', 'First expected link found.');
        $this->assertEqual($list_elements->item(1)->nodeValue, 'Second child link', 'Second expected link found.');
        $this->assertStringNotContainsString('First child link', $parent_html, '"First child link" link not found.');
        $this->assertStringNotContainsString('Third child link', $parent_html, '"Third child link" link not found.');
    }
    
    /**
     * Test the use of drupal_pre_render_links() on a nested array of links.
     *
     * @group legacy
     *
     * @expectedDeprecation Render #pre_render callbacks must be methods of a class that implements \Drupal\Core\Security\TrustedCallbackInterface or be an anonymous function. The callback was drupal_pre_render_links. Support for this callback implementation is deprecated in 8.8.0 and will be removed in Drupal 9.0.0. See https://www.drupal.org/node/2966725
     * @expectedDeprecation drupal_pre_render_links() is deprecated in Drupal 8.8.0 and will be removed before Drupal 9.0.0. Use \Drupal\Core\Render\Element\Link::preRenderLinks() instead. See https://www.drupal.org/node/2966725
     */
    public function testDrupalPreRenderLinksLegacy() {
        // Define the base array to be rendered, containing a variety of different
        // kinds of links.
        $base_array = [
            '#theme' => 'links',
            '#pre_render' => [
                'drupal_pre_render_links',
            ],
            '#links' => [
                'parent_link' => [
                    'title' => 'Parent link original',
                    'url' => Url::fromRoute('router_test.1'),
                ],
            ],
            'first_child' => [
                '#theme' => 'links',
                '#links' => [
                    // This should be rendered if 'first_child' is rendered separately,
                    // but ignored if the parent is being rendered (since it duplicates
                    // one of the parent's links).
'parent_link' => [
                        'title' => 'Parent link copy',
                        'url' => Url::fromRoute('router_test.6'),
                    ],
                    // This should always be rendered.
'first_child_link' => [
                        'title' => 'First child link',
                        'url' => Url::fromRoute('router_test.7'),
                    ],
                ],
            ],
            // This should always be rendered as part of the parent.
'second_child' => [
                '#theme' => 'links',
                '#links' => [
                    'second_child_link' => [
                        'title' => 'Second child link',
                        'url' => Url::fromRoute('router_test.8'),
                    ],
                ],
            ],
            // This should never be rendered, since the user does not have access to
            // it.
'third_child' => [
                '#theme' => 'links',
                '#links' => [
                    'third_child_link' => [
                        'title' => 'Third child link',
                        'url' => Url::fromRoute('router_test.9'),
                    ],
                ],
                '#access' => FALSE,
            ],
        ];
        // Start with a fresh copy of the base array, and try rendering the entire
        // thing. We expect a single <ul> with appropriate links contained within
        // it.
        $render_array = $base_array;
        $html = \Drupal::service('renderer')->renderRoot($render_array);
        $dom = new \DOMDocument();
        $dom->loadHTML($html);
        $this->assertEqual($dom->getElementsByTagName('ul')->length, 1, 'One "ul" tag found in the rendered HTML.');
        $list_elements = $dom->getElementsByTagName('li');
        $this->assertEqual($list_elements->length, 3, 'Three "li" tags found in the rendered HTML.');
        $this->assertEqual($list_elements->item(0)->nodeValue, 'Parent link original', 'First expected link found.');
        $this->assertEqual($list_elements->item(1)->nodeValue, 'First child link', 'Second expected link found.');
        $this->assertEqual($list_elements->item(2)->nodeValue, 'Second child link', 'Third expected link found.');
        $this->assertIdentical(strpos($html, 'Parent link copy'), FALSE, '"Parent link copy" link not found.');
        $this->assertIdentical(strpos($html, 'Third child link'), FALSE, '"Third child link" link not found.');
        // Now render 'first_child', followed by the rest of the links, and make
        // sure we get two separate <ul>'s with the appropriate links contained
        // within each.
        $render_array = $base_array;
        $child_html = \Drupal::service('renderer')->renderRoot($render_array['first_child']);
        $parent_html = \Drupal::service('renderer')->renderRoot($render_array);
        // First check the child HTML.
        $dom = new \DOMDocument();
        $dom->loadHTML($child_html);
        $this->assertEqual($dom->getElementsByTagName('ul')->length, 1, 'One "ul" tag found in the rendered child HTML.');
        $list_elements = $dom->getElementsByTagName('li');
        $this->assertEqual($list_elements->length, 2, 'Two "li" tags found in the rendered child HTML.');
        $this->assertEqual($list_elements->item(0)->nodeValue, 'Parent link copy', 'First expected link found.');
        $this->assertEqual($list_elements->item(1)->nodeValue, 'First child link', 'Second expected link found.');
        // Then check the parent HTML.
        $dom = new \DOMDocument();
        $dom->loadHTML($parent_html);
        $this->assertEqual($dom->getElementsByTagName('ul')->length, 1, 'One "ul" tag found in the rendered parent HTML.');
        $list_elements = $dom->getElementsByTagName('li');
        $this->assertEqual($list_elements->length, 2, 'Two "li" tags found in the rendered parent HTML.');
        $this->assertEqual($list_elements->item(0)->nodeValue, 'Parent link original', 'First expected link found.');
        $this->assertEqual($list_elements->item(1)->nodeValue, 'Second child link', 'Second expected link found.');
        $this->assertIdentical(strpos($parent_html, 'First child link'), FALSE, '"First child link" link not found.');
        $this->assertIdentical(strpos($parent_html, 'Third child link'), FALSE, '"Third child link" link not found.');
    }
    
    /**
     * Tests theme_image().
     */
    public function testImage() {
        // Test that data URIs work with theme_image().
        $variables = [];
        $variables['uri'] = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==';
        $variables['alt'] = 'Data URI image of a red dot';
        $expected = '<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Data URI image of a red dot" />' . "\n";
        $this->assertThemeOutput('image', $variables, $expected);
    }

}