Skip to content
Switch branches/tags
Go to file
Cannot retrieve contributors at this time
.. index::
    single: Getting Started; Simple Example

Simple Example

Imagine we have a Temperature class which samples the temperature of a locale before reporting an average temperature. The data could come from a web service or any other data source, but we do not have such a class at present. We can, however, assume some basic interactions with such a class based on its interaction with the Temperature class:

class Temperature
    private $service;

    public function __construct($service)
        $this->service = $service;

    public function average()
        $total = 0;
        for ($i=0; $i<3; $i++) {
            $total += $this->service->readTemp();
        return $total/3;

Even without an actual service class, we can see how we expect it to operate. When writing a test for the Temperature class, we can now substitute a mock object for the real service which allows us to test the behaviour of the Temperature class without actually needing a concrete service instance.

use \Mockery;

class TemperatureTest extends \PHPUnit\Framework\TestCase
    public function tearDown()

    public function testGetsAverageTemperatureFromThreeServiceReadings()
        $service = Mockery::mock('service');
            ->andReturn(10, 12, 14);

        $temperature = new Temperature($service);

        $this->assertEquals(12, $temperature->average());

We create a mock object which our Temperature class will use and set some expectations for that mock — that it should receive three calls to the readTemp method, and these calls will return 10, 12, and 14 as results.


PHPUnit integration can remove the need for a tearDown() method. See ":doc:`/reference/phpunit_integration`" for more information.