Behat for Drupal 8.

The module provide BDD testing framework for contribute components.

How it's works?

Each project that uses behat as a testing tool have a FeatureContext class that contains the step definition or any other additional information.

Each module will need to to implement a FeatureContext plugin that will keep the step definitions and other behat integration(i.e beforeScenario or afterScenario methods).

Define a plugin

Behat module implements a FeatureContext plugin:

<?php

/**
 * Contains Drupal\behat\Plugin\FeatureContext\FeatureContextBase.
 */
namespace Drupal\behat\Plugin\FeatureContext;

/**
 * @FeatureContext(
 *   id = "behat",
 *   label = @Translation("Behat"),
 * )
 *
 * @runTestsInSeparateProcesses
 * @preserveGlobalState disabled
 */
class FeatureContextBase extends BehatTestsAbstract {

  use BasicTrait;

  /**
   * {@inheritdoc}
   */
  public function beforeScenario(ScenarioInterface $scenarioInterface = NULL) {
    parent::beforeScenario($scenarioInterface);

    $account = $this->drupalCreateUser();
    $this->placeholders = [
      '@user-name' => $account->label(),
      '@user-pass' => $account->passRaw,
    ];
  }
}

This plugin implements a beforeScenario method to a create user for testing. The @runTestsInSeparateProcesses and @preserveGlobalState disabled annotation needed by the PHPUnit testing framework for fire up a mink browser environment.

Step definitions

As mentioned above, the FeatureContext plugin is replacing the FeatureContext class. That class will keep all the step definition.

The default step definitions defined in a trait. In this way other modules could provide more step definition and your FeatureContext could leverage them.

Cucumber files

By default all the feature files will be located at MODULE/src/Features. In the future, you could specify other folder location in the plugin definition.

Running the tests

There are two ways to run the tests. One way is using the UI under admin/config/development/behat and you can check which files you want to run. This isn't a good practice since it's not running in batch operation.

The best way is to use drush: drush bin/behat PROVIDER URL.

The PROVIDER is the ID for the FeatureContext plugin. In our case is behat.

The URL is the URL of your Drupal 8 installation.

For example: drush bin/behat behat http://localhost/drupal8

Running specific features could be done with the feature option: drush bin/behat behat http://localhost/drupal8 --features=login

This will run only the login.feature file defined by the behat module.