DependentDropdownTest.php

<?php

namespace Drupal\Tests\ajax_example\FunctionalJavascript;

use Drupal\Core\Url;
use Drupal\FunctionalJavascriptTests\WebDriverTestBase;

/**
 * Functional test of dependent dropdown example.
 *
 * @group ajax_example
 *
 * @see \Drupal\Tests\ajax_example\FunctionalJavascript\DependentDropdownTest
 */
class DependentDropdownTest extends WebDriverTestBase {
  
  /**
   * {@inheritdoc}
   */
  protected $defaultTheme = 'stark';
  
  /**
   * {@inheritdoc}
   */
  protected static $modules = [
    'ajax_example',
  ];
  
  /**
   * Test the dependent dropdown form with AJAX.
   */
  public function testDependentDropdown() {
    // Get the Mink stuff.
    $assert = $this->assertSession();
    $page = $this->getSession()
      ->getPage();
    // Get a URL object for the form, specifying AJAX.
    $dropdown_url = Url::fromRoute('ajax_example.dependent_dropdown');
    // Get the form.
    $this->drupalGet($dropdown_url);
    // Check for the initial state.
    $assert->fieldDisabled('instrument_dropdown');
    $assert->fieldValueEquals('instrument_dropdown', 'none');
    $submit_button = $page->findButton('edit-submit');
    $this->assertTrue($submit_button->hasAttribute('disabled'));
    // Run through the matrix of families.
    $families = [
      'String' => [
        'Violin',
        'Viola',
        'Cello',
        'Double Bass',
      ],
      'Woodwind' => [
        'Flute',
        'Clarinet',
        'Oboe',
        'Bassoon',
      ],
      'Brass' => [
        'Trumpet',
        'Trombone',
        'French Horn',
        'Euphonium',
      ],
      'Percussion' => [
        'Bass Drum',
        'Timpani',
        'Snare Drum',
        'Tambourine',
      ],
    ];
    foreach ($families as $family => $instruments) {
      // Select a family.
      $family_dropdown = $assert->fieldExists('instrument_family_dropdown');
      $family_dropdown->setValue($family);
      $assert->assertWaitOnAjaxRequest();
      // Get the instrument dropdown elements.
      $instrument_options = $page->findAll('css', 'select[name="instrument_dropdown"] option');
      $this->assertCount(count($instruments), $instrument_options);
      // Make sure all the instruments are in the select dropdown.
      foreach ($instrument_options as $instrument) {
        $this->assertContains($instrument->getAttribute('value'), $instruments);
      }
      // Post each instrument.
      foreach ($instruments as $instrument) {
        $this->drupalGet($dropdown_url);
        $assert->selectExists('instrument_family_dropdown')
          ->selectOption($family);
        $assert->assertWaitOnAjaxRequest();
        $assert->selectExists('instrument_dropdown')
          ->selectOption($instrument);
        $assert->buttonExists('Submit')
          ->press();
        $assert->pageTextContains("Your values have been submitted. Instrument family: {$family}, Instrument: {$instrument}");
      }
    }
  }

}