MailCaptureTest.php

<?php

declare (strict_types=1);
namespace Drupal\FunctionalTests;

use Drupal\Tests\BrowserTestBase;
use Drupal\Core\Test\AssertMailTrait;

/**
 * Tests the collection of emails during testing.
 *
 * The test mail collector, test.mail.collector, intercepts any email sent
 * during a test so it does not leave the test server.
 *
 * @group browsertestbase
 */
class MailCaptureTest extends BrowserTestBase {
    use AssertMailTrait {
        getMails as drupalGetMails;
    }
    
    /**
     * {@inheritdoc}
     */
    protected $defaultTheme = 'stark';
    
    /**
     * Tests to see if the wrapper function is executed correctly.
     */
    public function testMailSend() : void {
        // Create an email.
        $subject = $this->randomString(64);
        $body = $this->randomString(128);
        $message = [
            'id' => 'drupal_mail_test',
            'headers' => [
                'Content-type' => 'text/html',
            ],
            'subject' => $subject,
            'to' => 'foobar@example.com',
            'body' => $body,
        ];
        // Before we send the email, drupalGetMails should return an empty array.
        $captured_emails = $this->drupalGetMails();
        $this->assertCount(0, $captured_emails, 'The captured emails queue is empty.');
        // Send the email.
        \Drupal::service('plugin.manager.mail')->getInstance([
            'module' => 'test',
            'key' => 'drupal_mail_test',
        ])
            ->mail($message);
        // Ensure that there is one email in the captured emails array.
        $captured_emails = $this->drupalGetMails();
        $this->assertCount(1, $captured_emails, 'One email was captured.');
        // Assert that the email was sent by iterating over the message properties
        // and ensuring that they are captured intact.
        foreach ($message as $field => $value) {
            $this->assertMail($field, $value, "The email was sent and the value for property {$field} is intact.");
        }
        // Send additional emails so more than one email is captured.
        for ($index = 0; $index < 5; $index++) {
            $message = [
                'id' => 'drupal_mail_test_' . $index,
                'headers' => [
                    'Content-type' => 'text/html',
                ],
                'subject' => $this->randomString(64),
                'to' => $this->randomMachineName(32) . '@example.com',
                'body' => $this->randomString(512),
            ];
            \Drupal::service('plugin.manager.mail')->getInstance([
                'module' => 'drupal_mail_test',
                'key' => $index,
            ])
                ->mail($message);
        }
        // There should now be 6 emails captured.
        $captured_emails = $this->drupalGetMails();
        $this->assertCount(6, $captured_emails, 'All emails were captured.');
        // Test different ways of getting filtered emails via drupalGetMails().
        $captured_emails = $this->drupalGetMails([
            'id' => 'drupal_mail_test',
        ]);
        $this->assertCount(1, $captured_emails, 'Only one email is returned when filtering by id.');
        $captured_emails = $this->drupalGetMails([
            'id' => 'drupal_mail_test',
            'subject' => $subject,
        ]);
        $this->assertCount(1, $captured_emails, 'Only one email is returned when filtering by id and subject.');
        $captured_emails = $this->drupalGetMails([
            'id' => 'drupal_mail_test',
            'subject' => $subject,
            'from' => 'this_was_not_used@example.com',
        ]);
        $this->assertCount(0, $captured_emails, 'No emails are returned when querying with an unused from address.');
        // Send the last email again, so we can confirm that the
        // drupalGetMails-filter correctly returns all emails with a given
        // property/value.
        \Drupal::service('plugin.manager.mail')->getInstance([
            'module' => 'drupal_mail_test',
            'key' => $index,
        ])
            ->mail($message);
        $captured_emails = $this->drupalGetMails([
            'id' => 'drupal_mail_test_4',
        ]);
        $this->assertCount(2, $captured_emails, 'All emails with the same id are returned when filtering by id.');
    }

}