index.rst

Symfony2 Mocker Extension

Behat extension for mocking services defined in the Symfony2 dependency injection container.

Use it sparingly. Mocking a service container is not a good practice. Most of the time if there's a need for this, the problem can be better solved by improving the design instead.

Internally it uses Mockery and SymfonyMockerContainer.

Note

Mocking services in acceptance tests is not always the best option, but sometimes it is a necessity. Especially, if we don't have a possibility to use the service in a test mode to prevent interactions with the production environment.

Installation

This extension requires:

• Behat 3.0+

1. Install the extension:

   $ composer require polishsymfonycommunity/symfony2-mocker-extension

2. Activate it in behat.yml:

   default:
       # ...
   
       extensions:
           Behat\MinkExtension:
               sessions:
                   default:
                       symfony2: ~
           Behat\Symfony2Extension: ~
           PSS\Behat\Symfony2MockerExtension: ~

Enabling the mocker container

The base container class for the test environment needs to be replaced in app/AppKernel.php:

<?php

/**
 * @return string
 */
protected function getContainerBaseClass()
{
    if ('test' == $this->environment) {
        return '\PSS\SymfonyMockerContainer\DependencyInjection\MockerContainer';
    }

    return parent::getContainerBaseClass();
}

Note

Don't forget to clear your cache.

Usage

Simply add the ServiceMocker to the list of constructor arguments in the context file:

use Behat\Behat\Context\Context;
use PSS\Behat\Symfony2MockerExtension\ServiceMocker;

final class FeatureContext implements Context
{
    /**
     * @var ServiceMocker
     */
    private $serviceMocker;

    /**
     * @param ServiceMocker $serviceMocker
     */
    public function __construct(ServiceMocker $serviceMocker)
    {
        $this->serviceMocker = $serviceMocker;
    }

    /**
     * @Given /^CRM API is available$/
     */
    public function crmApiIsAvailable()
    {
        $this->serviceMocker->mockService('crm.client', 'PSS\Crm\Client')
            ->shouldReceive('send')
            ->once()
            ->andReturn(true);
    }
}

Example story

Imagine you're working on a following feature:

Feature: Submitting contact request form
  As a Visitor
  I want to contact sales
  In order to receive more information

  Scenario: Submitting the form
    When I go to "/contact-us"
     And I complete the contact us form with following information
       |First name|Last name|Email                |
       |Jakub     |Zalas    |jzalas+spam@gmail.com|
     And CRM API is available
     And I submit the contact us form
    Then the contact request should be sent to the CRM

You probably wouldn't like your CRM API to be hit every time scenarios are run. One way of solving this issue is to mock the service and only verify if it was called:

<?php

namespace PSS\Features\Context;

use Behat\Behat\Context\Context;
use PSS\Behat\Symfony2MockerExtension\ServiceMocker;

class AcmeContext implements Context
{
    /**
     * @var ServiceMocker
     */
    private $serviceMocker;

    /**
     * @param ServiceMocker $serviceMocker
     */
    public function __construct(ServiceMocker $serviceMocker)
    {
        $this->serviceMocker = $serviceMocker;
    }

    /**
     * @Given /^CRM API is available$/
     */
    public function crmApiIsAvailable()
    {
        $this->serviceMocker
            ->mockService('crm.client', 'PSS\Crm\Client')
            ->shouldReceive('send')
            ->once()
            ->andReturn(true);
    }

    /**
     * @Given /^(the )?contact request should be sent to (the )?CRM$/
     */
    public function theContactRequestShouldBeSentToCrm()
    {
        $this->serviceMocker->verifyServiceExpectationsById('crm.client');
    }
}

All the expectations are checked automatically with afterScenario and afterOutlineExample hooks. Doing it manually only improves the readability of the scenario and outputs a better error message.