Laravel 8.x Database Testing

Introduction

Laravel provides a variety of helpful tools and assertions to make it easier to test your database driven applications. In addition, Laravel model factories and seeders make it painless to create test database records using your application's Eloquent models and relationships. We'll discuss all of these powerful features in the following documentation.

Resetting The Database After Each Test

Before proceeding much further, let's discuss how to reset your database after each of your tests so that data from a previous test does not interfere with subsequent tests. Laravel's included Illuminate\Foundation\Testing\RefreshDatabase trait will take care of this for you. Simply use the trait on your test class:

<?php

namespace Tests\Feature;

use Illuminate\Foundation\Testing\RefreshDatabase;
use Illuminate\Foundation\Testing\WithoutMiddleware;
use Tests\TestCase;

class ExampleTest extends TestCase
{
    use RefreshDatabase;

    /**
     * A basic functional test example.
     *
     * @return void
     */
    public function test_basic_example()
    {
        $response = $this->get('/');

        // ...
    }
}

Defining Model Factories

Concept Overview

First, let's talk about Eloquent model factories. When testing, you may need to insert a few records into your database before executing your test. Instead of manually specifying the value of each column when you create this test data, Laravel allows you to define a set of default attributes for each of your Eloquent models using model factories.

To see an example of how to write a factory, take a look at the database/factories/UserFactory.php file in your application. This factory is included with all new Laravel applications and contains the following factory definition:

namespace Database\Factories;

use Illuminate\Database\Eloquent\Factories\Factory;
use Illuminate\Support\Str;

class UserFactory extends Factory
{
    /**
     * Define the model's default state.
     *
     * @return array
     */
    public function definition()
    {
        return [
            'name' => $this->faker->name(),
            'email' => $this->faker->unique()->safeEmail(),
            'email_verified_at' => now(),
            'password' => '$2y$10$92IXUNpkjO0rOQ5byMi.Ye4oKoEa3Ro9llC/.og/at2.uheWG/igi', // password
            'remember_token' => Str::random(10),
        ];
    }
}

As you can see, in their most basic form, factories are classes that extend Laravel's base factory class and define definition method. The definition method returns the default set of attribute values that should be applied when creating a model using the factory.

Via the faker property, factories have access to the Faker PHP library, which allows you to conveniently generate various kinds of random data for testing.

lightbulb">Tip!! You can set your application's Faker locale by adding a faker_locale option to your config/app.php configuration file.

Generating Factories

To create a factory, execute the make:factory Artisan command:

php artisan make:factory PostFactory

The new factory class will be placed in your database/factories directory.

Model & Factory Discovery Conventions

Once you have defined your factories, you may use the static factory method provided to your models by the Illuminate\Database\Eloquent\Factories\HasFactory trait in order to instantiate a factory instance for that model.

The HasFactory trait's factory method will use conventions to determine the proper factory for the model the trait is assigned to. Specifically, the method will look for a factory in the Database\Factories namespace that has a class name matching the model name and is suffixed with Factory. If these conventions do not apply to your particular application or factory, you may overwrite the newFactory method on your model to return an instance of the model's corresponding factory directly:

use Database\Factories\Administration\FlightFactory;

/**
 * Create a new factory instance for the model.
 *
 * @return \Illuminate\Database\Eloquent\Factories\Factory
 */
protected static function newFactory()
{
    return FlightFactory::new();
}

Next, define a model property on the corresponding factory:

use App\Administration\Flight;
use Illuminate\Database\Eloquent\Factories\Factory;

class FlightFactory extends Factory
{
    /**
     * The name of the factory's corresponding model.
     *
     * @var string
     */
    protected $model = Flight::class;
}

Factory States

State manipulation methods allow you to define discrete modifications that can be applied to your model factories in any combination. For example, your Database\Factories\UserFactory factory might contain a suspended state method that modifies one of its default attribute values.

State transformation methods typically call the state method provided by Laravel's base factory class. The state method accepts a closure which will receive the array of raw attributes defined for the factory and should return an array of attributes to modify:

/**
 * Indicate that the user is suspended.
 *
 * @return \Illuminate\Database\Eloquent\Factories\Factory
 */
public function suspended()
{
    return $this->state(function (array $attributes) {
        return [
            'account_status' => 'suspended',
        ];
    });
}

Factory Callbacks

Factory callbacks are registered using the afterMaking and afterCreating methods and allow you to perform additional tasks after making or creating a model. You should register these callbacks by defining a configure method on your factory class. This method will be automatically called by Laravel when the factory is instantiated:

namespace Database\Factories;

use App\Models\User;
use Illuminate\Database\Eloquent\Factories\Factory;
use Illuminate\Support\Str;

class UserFactory extends Factory
{
    /**
     * Configure the model factory.
     *
     * @return $this
     */
    public function configure()
    {
        return $this->afterMaking(function (User $user) {
            //
        })->afterCreating(function (User $user) {
            //
        });
    }

    // ...
}

Creating Models Using Factories

Instantiating Models

Once you have defined your factories, you may use the static factory method provided to your models by the Illuminate\Database\Eloquent\Factories\HasFactory trait in order to instantiate a factory instance for that model. Let's take a look at a few examples of creating models. First, we'll use the make method to create models without persisting them to the database:

use App\Models\User;

public function test_models_can_be_instantiated()
{
    $user = User::factory()->make();

    // Use model in tests...
}

You may create a collection of many models using the count method:

$users = User::factory()->count(3)->make();

Applying States

You may also apply any of your states to the models. If you would like to apply multiple state transformations to the models, you may simply call the state transformation methods directly:

$users = User::factory()->count(5)->suspended()->make();

Overriding Attributes

If you would like to override some of the default values of your models, you may pass an array of values to the make method. Only the specified attributes will be replaced while the rest of the attributes remain set to their default values as specified by the factory:

$user = User::factory()->make([
    'name' => 'Abigail Otwell',
]);

Alternatively, the state method may be called directly on the factory instance to perform an inline state transformation:

$user = User::factory()->state([
    'name' => 'Abigail Otwell',
])->make();

lightbulb">Tip!! Mass assignment protection is automatically disabled when creating models using factories.

Persisting Models

The create method instantiates model instances and persists them to the database using Eloquent's save method:

use App\Models\User;

public function test_models_can_be_persisted()
{
    // Create a single App\Models\User instance...
    $user = User::factory()->create();

    // Create three App\Models\User instances...
    $users = User::factory()->count(3)->create();

    // Use model in tests...
}

You may override the factory's default model attributes by passing an array of attributes to the create method:

$user = User::factory()->create([
    'name' => 'Abigail',
]);

Sequences

Sometimes you may wish to alternate the value of a given model attribute for each created model. You may accomplish this by defining a state transformation as a sequence. For example, you may wish to alternate the value of an admin column between Y and N for each created user:

use App\Models\User;
use Illuminate\Database\Eloquent\Factories\Sequence;

$users = User::factory()
                ->count(10)
                ->state(new Sequence(
                    ['admin' => 'Y'],
                    ['admin' => 'N'],
                ))
                ->create();

In this example, five users will be created with an admin value of Y and five users will be created with an admin value of N.

If necessary, you may include a closure as a sequence value. The closure will be invoked each time the sequence needs a new value:

$users = User::factory()
                ->count(10)
                ->state(new Sequence(
                    fn ($sequence) => ['role' => UserRoles::all()->random()],
                ))
                ->create();

Within a sequence closure, you may access the $index or $count properties on the sequence instance that is injected into the closure. The $index property contains the number of iterations through the sequence that have occurred thus far, while the $count property contains the total number of times the sequence will be invoked:

$users = User::factory()
                ->count(10)
                ->sequence(fn ($sequence) => ['name' => 'Name '.$sequence->index])
                ->create();

Factory Relationships

Has Many Relationships

Next, let's explore building Eloquent model relationships using Laravel's fluent factory methods. First, let's assume our application has an App\Models\User model and an App\Models\Post model. Also, let's assume that the User model defines a hasMany relationship with Post. We can create a user that has three posts using the has method provided by the Laravel's factories. The has method accepts a factory instance:

use App\Models\Post;
use App\Models\User;

$user = User::factory()
            ->has(Post::factory()->count(3))
            ->create();

By convention, when passing a Post model to the has method, Laravel will assume that the User model must have a posts method that defines the relationship. If necessary, you may explicitly specify the name of the relationship that you would like to manipulate:

$user = User::factory()
            ->has(Post::factory()->count(3), 'posts')
            ->create();

Of course, you may perform state manipulations on the related models. In addition, you may pass a closure based state transformation if your state change requires access to the parent model:

$user = User::factory()
            ->has(
                Post::factory()
                        ->count(3)
                        ->state(function (array $attributes, User $user) {
                            return ['user_type' => $user->type];
                        })
            )
            ->create();

Using Magic Methods

For convenience, you may use Laravel's magic factory relationship methods to build relationships. For example, the following example will use convention to determine that the related models should be created via a posts relationship method on the User model:

$user = User::factory()
            ->hasPosts(3)
            ->create();

When using magic methods to create factory relationships, you may pass an array of attributes to override on the related models:

$user = User::factory()
            ->hasPosts(3, [
                'published' => false,
            ])
            ->create();

You may provide a closure based state transformation if your state change requires access to the parent model:

$user = User::factory()
            ->hasPosts(3, function (array $attributes, User $user) {
                return ['user_type' => $user->type];
            })
            ->create();

Belongs To Relationships

Now that we have explored how to build "has many" relationships using factories, let's explore the inverse of the relationship. The for method may be used to define the parent model that factory created models belong to. For example, we can create three App\Models\Post model instances that belong to a single user:

use App\Models\Post;
use App\Models\User;

$posts = Post::factory()
            ->count(3)
            ->for(User::factory()->state([
                'name' => 'Jessica Archer',
            ]))
            ->create();

If you already have a parent model instance that should be associated with the models you are creating, you may pass the model instance to the for method:

$user = User::factory()->create();

$posts = Post::factory()
            ->count(3)
            ->for($user)
            ->create();

Using Magic Methods

For convenience, you may use Laravel's magic factory relationship methods to define "belongs to" relationships. For example, the following example will use convention to determine that the three posts should belong to the user relationship on the Post model:

$posts = Post::factory()
            ->count(3)
            ->forUser([
                'name' => 'Jessica Archer',
            ])
            ->create();

Many To Many Relationships

Like has many relationships, "many to many" relationships may be created using the has method:

use App\Models\Role;
use App\Models\User;

$user = User::factory()
            ->has(Role::factory()->count(3))
            ->create();

Pivot Table Attributes

If you need to define attributes that should be set on the pivot / intermediate table linking the models, you may use the hasAttached method. This method accepts an array of pivot table attribute names and values as its second argument:

use App\Models\Role;
use App\Models\User;

$user = User::factory()
            ->hasAttached(
                Role::factory()->count(3),
                ['active' => true]
            )
            ->create();

You may provide a closure based state transformation if your state change requires access to the related model:

$user = User::factory()
            ->hasAttached(
                Role::factory()
                    ->count(3)
                    ->state(function (array $attributes, User $user) {
                        return ['name' => $user->name.' Role'];
                    }),
                ['active' => true]
            )
            ->create();

If you already have model instances that you would like to be attached to the models you are creating, you may pass the model instances to the hasAttached method. In this example, the same three roles will be attached to all three users:

$roles = Role::factory()->count(3)->create();

$user = User::factory()
            ->count(3)
            ->hasAttached($roles, ['active' => true])
            ->create();

Using Magic Methods

For convenience, you may use Laravel's magic factory relationship methods to define many to many relationships. For example, the following example will use convention to determine that the related models should be created via a roles relationship method on the User model:

$user = User::factory()
            ->hasRoles(1, [
                'name' => 'Editor'
            ])
            ->create();

Polymorphic Relationships

Polymorphic relationships may also be created using factories. Polymorphic "morph many" relationships are created in the same way as typical "has many" relationships. For example, if a App\Models\Post model has a morphMany relationship with a App\Models\Comment model:

use App\Models\Post;

$post = Post::factory()->hasComments(3)->create();

Morph To Relationships

Magic methods may not be used to create morphTo relationships. Instead, the for method must be used directly and the name of the relationship must be explicitly provided. For example, imagine that the Comment model has a commentable method that defines a morphTo relationship. In this situation, we may create three comments that belong to a single post by using the for method directly:

$comments = Comment::factory()->count(3)->for(
    Post::factory(), 'commentable'
)->create();

Polymorphic Many To Many Relationships

Polymorphic "many to many" (morphToMany / morphedByMany) relationships may be created just like non-polymorphic "many to many" relationships:

use App\Models\Tag;
use App\Models\Video;

$videos = Video::factory()
            ->hasAttached(
                Tag::factory()->count(3),
                ['public' => true]
            )
            ->create();

Of course, the magic has method may also be used to create polymorphic "many to many" relationships:

$videos = Video::factory()
            ->hasTags(3, ['public' => true])
            ->create();

Defining Relationships Within Factories

To define a relationship within your model factory, you will typically assign a new factory instance to the foreign key of the relationship. This is normally done for the "inverse" relationships such as belongsTo and morphTo relationships. For example, if you would like to create a new user when creating a post, you may do the following:

use App\Models\User;

/**
 * Define the model's default state.
 *
 * @return array
 */
public function definition()
{
    return [
        'user_id' => User::factory(),
        'title' => $this->faker->title(),
        'content' => $this->faker->paragraph(),
    ];
}

If the relationship's columns depend on the factory that defines it you may assign a closure to an attribute. The closure will receive the factory's evaluated attribute array:

/**
 * Define the model's default state.
 *
 * @return array
 */
public function definition()
{
    return [
        'user_id' => User::factory(),
        'user_type' => function (array $attributes) {
            return User::find($attributes['user_id'])->type;
        },
        'title' => $this->faker->title(),
        'content' => $this->faker->paragraph(),
    ];
}

Running Seeders

If you would like to use database seeders to populate your database during a feature test, you may invoke the seed method. By default, the seed method will execute the DatabaseSeeder, which should execute all of your other seeders. Alternatively, you pass a specific seeder class name to the seed method:

<?php

namespace Tests\Feature;

use Database\Seeders\OrderStatusSeeder;
use Database\Seeders\TransactionStatusSeeder;
use Illuminate\Foundation\Testing\RefreshDatabase;
use Illuminate\Foundation\Testing\WithoutMiddleware;
use Tests\TestCase;

class ExampleTest extends TestCase
{
    use RefreshDatabase;

    /**
     * Test creating a new order.
     *
     * @return void
     */
    public function test_orders_can_be_created()
    {
        // Run the DatabaseSeeder...
        $this->seed();

        // Run a specific seeder...
        $this->seed(OrderStatusSeeder::class);

        // ...

        // Run an array of specific seeders...
        $this->seed([
            OrderStatusSeeder::class,
            TransactionStatusSeeder::class,
            // ...
        ]);
    }
}

Alternatively, you may instruct Laravel to automatically seed the database before each test that uses the RefreshDatabase trait. You may accomplish this by defining a $seed property on your base test class:

<?php

namespace Tests;

use Illuminate\Foundation\Testing\TestCase as BaseTestCase;

abstract class TestCase extends BaseTestCase
{
    use CreatesApplication;

    /**
     * Indicates whether the default seeder should run before each test.
     *
     * @var bool
     */
    protected $seed = true;
}

When the $seed property is true, the test will run the Database\Seeders\DatabaseSeeder class before each test that uses the RefreshDatabase trait. However, you may specify a specific seeder that should be executed by defining a $seeder property on your test class:

use Database\Seeders\OrderStatusSeeder;

/**
 * Run a specific seeder before each test.
 *
 * @var string
 */
protected $seeder = OrderStatusSeeder::class;

Available Assertions

Laravel provides several database assertions for your PHPUnit feature tests. We'll discuss each of these assertions below.

assertDatabaseCount

Assert that a table in the database contains the given number of records:

$this->assertDatabaseCount('users', 5);

assertDatabaseHas

Assert that a table in the database contains records matching the given key / value query constraints:

$this->assertDatabaseHas('users', [
    'email' => 'sally@example.com',
]);

assertDatabaseMissing

Assert that a table in the database does not contain records matching the given key / value query constraints:

$this->assertDatabaseMissing('users', [
    'email' => 'sally@example.com',
]);

assertDeleted

The assertDeleted asserts that a given Eloquent model has been deleted from the database:

use App\Models\User;

$user = User::find(1);

$user->delete();

$this->assertDeleted($user);

The assertSoftDeleted method may be used to assert a given Eloquent model has been "soft deleted":

$this->assertSoftDeleted($user);

assertModelExists

Assert that a given model exists in the database:

use App\Models\User;

$user = User::factory()->create();

$this->assertModelExists($user);

assertModelMissing

Assert that a given model does not exist in the database:

use App\Models\User;

$user = User::factory()->create();

$user->delete();

$this->assertModelMissing($user);