By Loïc d'Anterroches, xhtml.net, 18th of February, 2011

Testing a Photon Component, Application or Project

Automated testing improves the software quality by preventing regressions in the code. After and while implementing new features, you create and run the software unit tests to ensure that you do not break anything and that the software runs as expected. Photon provides an easy way to run your tests.

Introduction

Software testing is a very large field but the goal is always the same, getting a software with the minimum number of bugs and doing what it is supposed to do.

Photon provides you with some tools to help you perform some of the testing of your software, the tools covers:

Unit testing with PHPUnit;
Code coverage analysis with PHPUnit and X-Debug;
Continuous integration (planned);
Performance analysis.

You will need to manage yourself all the end user testing and in browser testing.

How to Run the Unit Tests

The unit tests with Photon are conventional PHPUnit tests. Go in project folder, where the config.test.php is available and simply run:

$ hnu selftest
Photon 0.0.1 by Loïc d'Anterroches and contributors.
Using PHPUnit 3.5.5 by Sebastian Bergmann.

............................................................  60 / 117
.........................................................

Time: 3 seconds, Memory: 10.25Mb

OK (117 tests, 186 assertions)

Writing code coverage data to XML file, this may take a moment.
Code coverage 1329/1338 (99.33%)

You see here that it automatically find the tests, run them and perform a code coverage analysis of your code. In this case, all the tests were ok but the code coverage is not good, it should be 100%.

How to Write the Unit Tests

First you need to know a bit PHPUnit, because this is the framework used to write the tests. The choice of PHPUnit was influenced by the active development and ecosystem around this framework. Basically, this is the standard unit testing library for PHP and it had the nice idea to decrease its level of bloat for the programmers in the last release.

The simplest test is a tests.php file in your application folder, for example: yourproject\apps\helloworld\tests.php. Just put:

<?php
namespace helloworld\tests;
class MySimpleTest extends \PHPUnit_Framework_TestCase
{
    /**
     * This will load the test configuration for your tests.
     */
    public function setUp()
    {
        \photon\test\Config::load();
    }

    /**
     * Simply test that foo returns true.
     *
     * It does not try to retrieve the data afterwards.
     */
    public function testHelloFoo()
    {
        $this->assertEquals(true, \helloworld\hello\Base::foo('yeah'));
    }

    /**
     * Simple failed test.
     */
    public function testHelloFailed()
    {
        $this->assertEquals(true, false);
    }
}

Then run:

$ hnu runtests

and enjoy the testing. What you need to notice is:

you extend \PHPUnit_Framework_TestCase and not PHPUnit_Framework_TestCase. The backslash in front is important as the class lives in the global namespace.
you can also have more test namespaces, as long as they are sub namespaces of yourapplication\tests and the files in the yourproject/apps/yourapplication/tests/ folder.
you need to load the configuration of your project in the setUp() call.

At the end, you write your tests exactly as you would write them with PHPUnit. You can even run PHPUnit yourself from the command line to test your application. This is very important to allow you to reuse code from other projects into your own Photon projects. That is, Photon will not force you to rewrite your tests just to go well with it. Photon is just bootstrapping PHPUnit for you.

Complex Unit Tests

In the real world, unit tests need to interact with your database, other web services and maybe other ØMQ components. This means that you need to provide your unit tests with some special configuration. You may also want to run some complex operations at the start of the tests.

By default, Photon uses:

config.test.php file in your project folder for your project configuration;
photon/testbootstrap.php to setup the auto loading of the classes and load your configuration.

You can use different configuration files, to run your tests with different setup, by using the --conf option, for example: --conf=other/config.test.php. For a small level of security, if the configuration file is named config.php the tests will not run. This is just to avoid you the bad luck of running your tests with your production settings by mistake...

You can use a different bootstrap file with the --bootstrap=path/to/bootstrap.php option.

Self Testing of Photon

To test your Photon installation, you can run the self test procedure:

$ hnu selftest