Overview

Prepare to write tests using SQLite in Laravel 5.4.

Prerequisites

Basic knowledge of Laravel
Migration files prepared

Edit phpunit.xml

Add the following three lines. We will use SQLite's in-memory feature.

    <php>
        <env name="APP_ENV" value="testing"/>
        <env name="CACHE_DRIVER" value="array"/>
        <env name="SESSION_DRIVER" value="array"/>
        <env name="QUEUE_DRIVER" value="sync"/>
        <env name="DB_CONNECTION" value="sqlite"/> // Add
        <env name="DB_DATABASE" value=":memory:"/> // Add
        <env name="ADMIN_DOMAIN" value="localhost"/> // Add
    </php>

Edit ModelFactory

Prepare this as needed. Omitted.

Write Tests

<testsuites>
        <testsuite name="Application Test Suite">
            <directory suffix="Test.php">./tests</directory>
        </testsuite>
</testsuites>

By default, phpunit.xml is set to execute any file ending with Test.php under the tests directory, so prepare your test files accordingly.

<?php

use Illuminate\Foundation\Testing\WithoutMiddleware;
use Illuminate\Foundation\Testing\DatabaseMigrations;
use Illuminate\Foundation\Testing\DatabaseTransactions;

class PostTest extends TestCase
{
    use DatabaseMigrations; // Run migration

    public function testIndex()
    {
        $user = factory(App\User::class)->create();

        var_dump($user->first()); // Check the data

        // Here is your tests...
    }
}