PHPUnit einrichten und den ersten Test schreiben

Was ist PHPUnit?

PHPUnit installieren

$ composer require --dev phpunit/phpunit "^11.0"

Konfiguration mit phpunit.xml

<?xml version="1.0" encoding="UTF-8"?>
<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="vendor/phpunit/phpunit/phpunit.xsd"
         bootstrap="vendor/autoload.php">
    <testsuites>
        <testsuite name="Unit">
            <directory>tests/</directory>
        </testsuite>
    </testsuites>
</phpunit>

Eine Testklasse schreiben

<?php
use PHPUnit\Framework\TestCase;

class CalculatorTest extends TestCase
{
    public function test_addition(): void
    {
        $calc = new Calculator();
        $this->assertEquals(5, $calc->add(2, 3));
    }
}

Die zu testende Klasse

<?php
class Calculator
{
    public function add(int $a, int $b): int
    {
        return $a + $b;
    }
}

Tests ausführen

$ vendor/bin/phpunit
...
OK (1 test, 1 assertion)

Konventionen für Testnamen

<?php
/** @test */
public function addition_returns_correct_sum(): void
{
    $this->assertEquals(5, (new Calculator())->add(2, 3));
}

Verzeichnisstruktur

src/Calculator.php       → Calculator
tests/CalculatorTest.php → CalculatorTest

setUp() und tearDown()

<?php
protected function setUp(): void
{
    $this->calc = new Calculator();
}

public function test_add(): void
{
    $this->assertEquals(7, $this->calc->add(3, 4));
}

setUpBeforeClass() und tearDownAfterClass()

Codeabdeckung

$ vendor/bin/phpunit --coverage-html coverage/

Zusammenfassung

Schnelltest