ResponseTest.php

<?php

namespace Drupal\Tests\system\Functional\Form;

use Drupal\Component\Serialization\Json;
use Drupal\Tests\BrowserTestBase;

/**
 * Tests the form API Response element.
 *
 * @group Form
 */
class ResponseTest extends BrowserTestBase {
    
    /**
     * Modules to enable.
     *
     * @var array
     */
    protected static $modules = [
        'form_test',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected $defaultTheme = 'stark';
    
    /**
     * Tests that enforced responses propagate through subscribers and middleware.
     */
    public function testFormResponse() {
        $edit = [
            'content' => $this->randomString(),
            'status' => 200,
        ];
        $this->drupalGet('form-test/response');
        $this->submitForm($edit, 'Submit');
        $content = Json::decode($this->getSession()
            ->getPage()
            ->getContent());
        $this->assertSession()
            ->statusCodeEquals(200);
        $this->assertSame($edit['content'], $content, 'Response content matches');
        // Verify that response was handled by kernel response subscriber.
        $this->assertSession()
            ->responseHeaderEquals('X-Form-Test-Response-Event', 'invoked');
        // Verify that response was handled by kernel middleware.
        $this->assertSession()
            ->responseHeaderEquals('X-Form-Test-Stack-Middleware', 'invoked');
        $edit = [
            'content' => $this->randomString(),
            'status' => 418,
        ];
        $this->drupalGet('form-test/response');
        $this->submitForm($edit, 'Submit');
        $content = Json::decode($this->getSession()
            ->getPage()
            ->getContent());
        $this->assertSession()
            ->statusCodeEquals(418);
        $this->assertSame($edit['content'], $content, 'Response content matches');
        // Verify that response was handled by kernel response subscriber.
        $this->assertSession()
            ->responseHeaderEquals('X-Form-Test-Response-Event', 'invoked');
        // Verify that response was handled by kernel middleware.
        $this->assertSession()
            ->responseHeaderEquals('X-Form-Test-Stack-Middleware', 'invoked');
    }

}