symfony3 Testing Simple Testing in Symfony3

Example

Unit Test

Unit tests are used to ensure that your code has no syntax error and to test the logic of your code to work as what you expected. Quick example:

src/AppBundle/Calculator/BillCalculator.php

<?php

namespace AppBundle\Calculator;

use AppBundle\Calculator\TaxCalculator;

class BillCalculator
{
    private $taxCalculator;

    public function __construct(TaxCalculator $taxCalculator)
    {
        $this->taxCalculator = $taxCalculator;
    }

    public function calculate($products)
    {
        $totalPrice = 0;
        foreach ($products as $product) {
            $totalPrice += $product['price'];
        }
        $tax = $this->taxCalculator->calculate($totalPrice);
        
        return $totalPrice + $tax;
    }
}

src/AppBundle/Calculator/TaxCalculator.php

<?php

namespace AppBundle\Calculator;

class TaxCalculator
{
    public function calculate($price)
    {
        return $price * 0.1; // for example the tax is 10%
    }
}

tests/AppBundle/Calculator/BillCalculatorTest.php

<?php

namespace Tests\AppBundle\Calculator;

class BillCalculatorTest extends \PHPUnit_Framework_TestCase
{
    public function testCalculate()
    {
        $products = [
            [
                'name' => 'A',
                'price' => 100,
            ],
            [
                'name' => 'B',
                'price' => 200,
            ],
        ];
        $taxCalculator = $this->getMock(\AppBundle\Calculator\TaxCalculator::class);

        // I expect my BillCalculator to call $taxCalculator->calculate once
        // with 300 as the parameter
        $taxCalculator->expects($this->once())->method('calculate')->with(300)->willReturn(30);

        $billCalculator = new BillCalculator($taxCalculator);
        $price = $billCalculator->calculate($products);

        $this->assertEquals(330, $price);
    }
}

I tested my BillCalculator class so I can ensure that my BillCalculator will return total products price + 10% tax. In unit test, we create our own test case. In this test, I provide 2 products (the prices are 100 and 200), so the tax will be 10% = 30. I expect the TaxCalculator to return 30, so that the total price will be 300 + 30 = 330.

Functional Test

Functional tests are used to test the input and output. With the given input, I expected some output without testing the process to create the output. (this is different with unit test because in unit test, we test the code flow). Quick example:

namespace Tests\AppBundle;

use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;

class ApplicationAvailabilityFunctionalTest extends WebTestCase
{
    /**
     * @dataProvider urlProvider
     */
    public function testPageIsSuccessful($url)
    {
        $client = self::createClient();
        $client->request('GET', $url);

        $this->assertTrue($client->getResponse()->isSuccessful());
    }

    public function urlProvider()
    {
        return array(
            array('/'),
            array('/posts'),
            array('/post/fixture-post-1'),
            array('/blog/category/fixture-category'),
            array('/archives'),
            // ...
        );
    }
}

I tested my controller so i can ensure that my controller will return 200 response instead of 400 (Not Found) or 500 (Internal Server Error) with the given url.

References:

• http://symfony.com/doc/current/best_practices/tests.html
• http://symfony.com/doc/current/book/testing.html