PageRenderTest.php

<?php

namespace Drupal\Tests\system\Kernel\Common;

use Drupal\KernelTests\KernelTestBase;

/**
 * Test page rendering hooks.
 *
 * @group system
 */
class PageRenderTest extends KernelTestBase {
    
    /**
     * Tests hook_page_attachments() exceptions.
     */
    public function testHookPageAttachmentsExceptions() {
        $this->enableModules([
            'common_test',
            'system',
        ]);
        \Drupal::service('router.builder')->rebuild();
        $this->assertPageRenderHookExceptions('common_test', 'hook_page_attachments');
    }
    
    /**
     * Tests hook_page_attachments_alter() exceptions.
     */
    public function testHookPageAlter() {
        $this->enableModules([
            'common_test',
            'system',
        ]);
        \Drupal::service('router.builder')->rebuild();
        $this->assertPageRenderHookExceptions('common_test', 'hook_page_attachments_alter');
    }
    
    /**
     * Asserts whether expected exceptions are thrown for invalid hook implementations.
     *
     * @param string $module
     *   The module whose invalid logic in its hooks to enable.
     * @param string $hook
     *   The page render hook to assert expected exceptions for.
     */
    public function assertPageRenderHookExceptions($module, $hook) {
        $html_renderer = \Drupal::getContainer()->get('main_content_renderer.html');
        // Assert a valid hook implementation doesn't trigger an exception.
        $page = [];
        $html_renderer->invokePageAttachmentHooks($page);
        // Assert that hooks can set cache tags.
        $this->assertEqual($page['#cache']['tags'], [
            'example',
        ]);
        $this->assertEqual($page['#cache']['contexts'], [
            'user.permissions',
        ]);
        // Assert an invalid hook implementation doesn't trigger an exception.
        \Drupal::state()->set($module . '.' . $hook . '.descendant_attached', TRUE);
        $assertion = $hook . '() implementation that sets #attached on a descendant triggers an exception';
        $page = [];
        try {
            $html_renderer->invokePageAttachmentHooks($page);
            $this->error($assertion);
        } catch (\LogicException $e) {
            $this->assertEqual($e->getMessage(), 'Only #attached and #cache may be set in ' . $hook . '().');
        }
        \Drupal::state()->set('bc_test.' . $hook . '.descendant_attached', FALSE);
        // Assert an invalid hook implementation doesn't trigger an exception.
        \Drupal::state()->set('bc_test.' . $hook . '.render_array', TRUE);
        $assertion = $hook . '() implementation that sets a child render array triggers an exception';
        $page = [];
        try {
            $html_renderer->invokePageAttachmentHooks($page);
            $this->error($assertion);
        } catch (\LogicException $e) {
            $this->assertEqual($e->getMessage(), 'Only #attached and #cache may be set in ' . $hook . '().');
        }
        \Drupal::state()->set($module . '.' . $hook . '.render_array', FALSE);
    }

}