phpunit Getting started with phpunit Minimal example test

Example

Given a simple PHP class:

class Car
{
    private $speed = 0;

    public getSpeed() {
        return $this->speed;
    }

    public function accelerate($howMuch) {
        $this->speed += $howMuch;
    }
}

You can write a PHPUnit test which tests the behavior of the class under test by calling the public methods and check whether they function as expected:

class CarTest extends PHPUnit_Framework_TestCase
{
    public function testThatInitalSpeedIsZero() {
        $car = new Car();
        $this->assertSame(0, $car->getSpeed());
    }

    public function testThatItAccelerates() {
        $car = new Car();
        $car->accelerate(20);
        $this->assertSame(20, $car->getSpeed());
    }

    public function testThatSpeedSumsUp() {
        $car = new Car();
        $car->accelerate(30);
        $car->accelerate(50);
        $this->assertSame(80, $car->getSpeed());
    }
}

Important parts:

1. Test class needs to derive from PHPUnit_Framework_TestCase.
2. Each test function name should start with the prefix 'test'
3. Use $this->assert... functions to check expected values.