Getting Started with Unit Testing in Laravel

Unit testing is a crucial aspect of any robust software development process. In Laravel, a popular PHP framework, writing unit tests is not only easy but also highly encouraged. In this tutorial, we will go through the basics of writing unit tests in Laravel, ensuring the reliability and stability of the individual code units.

Prerequisites

Before diving into writing unit tests, make sure the following prerequisites be installed:

1. Composer

2. Laravel Installed

3. PHPUnit

Setting Up a Laravel Project

Use the following commands to set up a new project:

composer create-project --prefer-dist laravel/laravel my-laravel-app

cd my-laravel-app

Creating a Unit Test

Laravel provides a convenient Artisan command to generate a test class. Let’s create a simple unit test for a hypothetical `Calculator` class:

php artisan make:test CalculatorTest --unit

This will generate a test file located at `tests/Unit/CalculatorTest.php`. Open the file and you’ll see a basic test structure.

Writing a Unit Test

Now, let’s write a unit test for a basic addition method in our `Calculator` class. Open `CalculatorTest.php` and modify it as follows:

namespace Tests\Unit;

use PHPUnit\Framework\TestCase;
use App\Calculator;

class CalculatorTest extends TestCase
{
    public function testAddition()
    {
        $calculator = new Calculator();
        $result = $calculator->add(2, 3);

        $this->assertEquals(5, $result);
    }
}

In this example, assume we have a `Calculator` class in the `app` directory with an `add` method like that.

namespace App;

class Calculator
{
    public function add($a, $b)
    {
        return $a + $b;
    }
}

Running Unit Tests

To run the unit tests, use the following command:

php artisan test

This will execute all the tests in the `tests` directory.

Assertions

Laravel provides a variety of assertions that can be used in the tests. In this example, we used `assertEquals` to verify that the addition method returns the expected result. Explore other assertions and details in the official documentation https://laravel.com/docs/10.x/testing.

Conclusion

We’ve just written a first unit test in Laravel. As the application grows, writing tests for individual code units will become an integral part of the development process, ensuring that the code remains maintainable and reliable. Hope you enjoy that.

Asahi