Laravel Testing with TDD

Test-driven development for Laravel applications using PHPUnit, Pest, Laravel factories, and testing helpers.

When to Activate

• Writing new Laravel applications or features
• Implementing API endpoints with Sanctum or Passport authentication
• Testing Eloquent models, relationships, scopes, and accessors
• Setting up testing infrastructure for Laravel projects
• Writing feature tests for HTTP controllers and form requests
• Mocking external services (queues, mail, notifications, HTTP)

TDD Workflow for Laravel

Red-Green-Refactor Cycle

// Step 1: RED — Write a failing test
public function test_a_product_can_be_created(): void
{
    $product = Product::factory()->create(['name' => 'Test Product']);
    $this->assertDatabaseHas('products', ['name' => 'Test Product']);
}

// Step 2: GREEN — Write the migration, model, and factory
// Step 3: REFACTOR — Improve while keeping tests green

Setup

PHPUnit Configuration

<?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"
         colors="true">
    <testsuites>
        <testsuite name="Unit">
            <directory suffix="Test.php">tests/Unit</directory>
        </testsuite>
        <testsuite name="Feature">
            <directory suffix="Test.php">tests/Feature</directory>
        </testsuite>
    </testsuites>
    <php>
        <env name="APP_ENV" value="testing"/>
        <env name="BCRYPT_ROUNDS" value="4"/>
        <env name="CACHE_STORE" value="array"/>
        <env name="DB_CONNECTION" value="sqlite"/>
        <env name="DB_DATABASE" value=":memory:"/>
        <env name="MAIL_MAILER" value="array"/>
        <env name="QUEUE_CONNECTION" value="sync"/>
        <env name="SESSION_DRIVER" value="array"/>
    </php>
</phpunit>

Base TestCase Setup

namespace Tests;

use Illuminate\Foundation\Testing\TestCase as BaseTestCase;

abstract class TestCase extends BaseTestCase
{
    protected function setUp(): void
    {
        parent::setUp();
        // Call $this->withoutExceptionHandling() only in tests that
        // test non-HTTP exceptions; it suppresses assertStatus() etc.
    }

    // Helper: Authenticate and return user
    protected function actingAsUser(): mixed
    {
        $user = \App\Models\User::factory()->create();
        $this->actingAs($user);
        return $user;
    }

    protected function actingAsAdmin(): mixed
    {
        $admin = \App\Models\User::factory()->admin()->create();
        $this->actingAs($admin);
        return $admin;
    }
}

Model Factories

// database/factories/UserFactory.php
class UserFactory extends Factory
{
    protected static ?string $password = null;

    public function definition(): array
    {
        return [
            'name' => fake()->name(),
            'email' => fake()->unique()->safeEmail(),
            'email_verified_at' => now(),
            'password' => static::$password ??= Hash::make('password'),
            'remember_token' => Str::random(10),
            'role' => 'user',
        ];
    }

    public function admin(): static
    {
        return $this->state(fn (array $attributes) => ['role' => 'admin']);
    }

    public function unverified(): static
    {
        return $this->state(fn (array $attributes) => ['email_verified_at' => null]);
    }
}

// database/factories/ProductFactory.php
class ProductFactory extends Factory
{
    public function definition(): array
    {
        return [
            'name' => fake()->unique()->words(3, true),
            'slug' => fn (array $attrs) => Str::slug($attrs['name']),
            'description' => fake()->paragraph(),
            'price' => fake()->numberBetween(100, 100000),
            'stock' => fake()->numberBetween(0, 100),
            'is_active' => true,
            'user_id' => UserFactory::new(),
        ];
    }

    public function outOfStock(): static
    {
        return $this->state(fn (array $attributes) => ['stock' => 0]);
    }
}

Using Factories

$user = User::factory()->create();
$admin = User::factory()->admin()->create();
$product = Product::factory()->create(['user_id' => $user->id]);
$products = Product::factory()->count(10)->create();
$draft = Product::factory()->make(); // Not persisted

// With relationships

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