Artisan::call('migrate');
Artisan::call('db:seed');

/**
 * Creates the application.
 *
 * @return IlluminateFoundationApplication
 */
public function createApplication()
{
    return self::initialize();
}

private static $configurationApp = null;
public static function initialize(){

    if(is_null(self::$configurationApp)){
        $app = require __DIR__.'/../bootstrap/app.php';

        $app->loadEnvironmentFrom('.env.testing');

        $app->make(IlluminateContractsConsoleKernel::class)->bootstrap();

        if (config('database.default') == 'sqlite') {
            $db = app()->make('db');
            $db->connection()->getPdo()->exec("pragma foreign_keys=1");
        }

        Artisan::call('migrate');
        Artisan::call('db:seed');

        self::$configurationApp = $app;
        return $app;
    }

    return self::$configurationApp;
}

public function tearDown()
{
    if ($this->app) {
        foreach ($this->beforeApplicationDestroyedCallbacks as $callback) {
            call_user_func($callback);
        }

    }

    $this->setUpHasRun = false;

    if (property_exists($this, 'serverVariables')) {
        $this->serverVariables = [];
    }

    if (class_exists('Mockery')) {
        Mockery::close();
    }

    $this->afterApplicationCreatedCallbacks = [];
    $this->beforeApplicationDestroyedCallbacks = [];
}

protected static $applicationRefreshed = false;

/**
 * Refresh the application instance.
 *
 * @return void
 */
protected function forceRefreshApplication() {
    if (!is_null($this->app)) {
        $this->app->flush();
    }
    $this->app = null;
    self::$configurationApp = null;
    self::$applicationRefreshed = true;
    parent::refreshApplication();
}

if (self::$applicationRefreshed) {
        self::$applicationRefreshed = false;
        $this->app->flush();
        $this->app = null;
        self::$configurationApp = null;
}

php artisan migrate:rollback
php artisan migrate --seed
vendor/bin/phpunit

$ php artisan migrate --database=mysql_testing
$ php artisan db:seed --database=mysql_testing

'connections' => [
        'mysql' => [
            'driver'    => 'mysql',
            'host'      => env('DB_HOST', 'localhost'),
            'database'  => env('DB_DATABASE', 'forge'),
            'username'  => env('DB_USERNAME', 'forge'),
            'password'  => env('DB_PASSWORD', ''),
            'charset'   => 'utf8',
            'collation' => 'utf8_unicode_ci',
            'prefix'    => '',
            'strict'    => false,
        ],
        'mysql_testing' => [
            'driver'    => 'mysql',
            'host'      => env('DB_HOST', 'localhost'),
            'database'  => env('DB_TEST_DATABASE'),
            'username'  => env('DB_USERNAME', 'forge'),
            'password'  => env('DB_PASSWORD', ''),
            'charset'   => 'utf8',
            'collation' => 'utf8_unicode_ci',
            'prefix'    => '',
            'strict'    => false,
        ],
    ],

DB_DATABASE=abc
DB_TEST_DATABASE=abc_test

<?xml version="1.0" encoding="UTF-8"?>
<phpunit>
    ...
    <php>
        ...
        <env name="DB_CONNECTION" value="mysql_testing"/>
</php>

class MyTest extends TestCase
{
    use IlluminateFoundationTestingDatabaseTransactions;

    public function testSomething()
    {

<?php

class TestCase extends IlluminateFoundationTestingTestCase
{
    /**
     * The base URL to use while testing the application.
     *
     * @var string
     */
    protected $baseUrl = 'http://localhost';

    /**
     * Creates the application.
     *
     * @return IlluminateFoundationApplication
     */
    public function createApplication()
    {
        /** @var $app IlluminateFoundationApplication */
        $app = require __DIR__.'/../bootstrap/app.php';
        $app->loadEnvironmentFrom('.env.testing');

        $app->make(IlluminateContractsConsoleKernel::class)->bootstrap();

        return $app;
    }
}

APP_ENV=testing
APP_DEBUG=true
APP_KEY=xxx

DB_CONNECTION=mysql
DB_HOST=127.0.0.1
DB_DATABASE=abc_testing
DB_USERNAME=xxx
DB_PASSWORD=xxx

class MyTest extends TestCase
{
    public static function setUpBeforeClass()
    {
        $config = parse_ini_file(".env.testing");
        $username = $config['DB_USERNAME'];
        $password = $config['DB_PASSWORD'];
        $database = $config['DB_DATABASE'];
        $host = $config['DB_HOST'];

        // Create test database
        $connection = new PDO("mysql:host={$host}", $username, $password);
        $connection->query("DROP DATABASE IF EXISTS " . $database);
        $connection->query("CREATE DATABASE " . $database);
    }

    public function testHomePage()
    {
        Artisan::call('migrate');
        Artisan::call('db:seed');

        $this->visit('/')
             ->see('Home')
             ->see('Please sign in')
             ->dontSee('Logout');
    }

/**
 * Runs migrations for individual tests
 *
 * @param array $migrations
 * @return void
 */
public function migrate(array $migrations = [])
{
    $path = database_path('migrations');
    $migrator = app()->make('migrator');
    $migrator->getRepository()->createRepository();
    $files = $migrator->getMigrationFiles($path);

    if (!empty($migrations)) {
        $files = collect($files)->filter(
            function ($value, $key) use ($migrations) {
                if (in_array($key, $migrations)) {
                    return [$key => $value];
                }
            }
        )->all();
    }

    $migrator->requireFiles($files);
    $migrator->runPending($files);
}

/**
 * Runs some or all seeds
 *
 * @param string $seed
 * @return void
 */
public function seed(string $seed = '')
{
    $command = "db:seed";

    if (empty($seed)) {
        Artisan::call($command);
    } else {
        Artisan::call($command, ['--class' => $seed]);
    }
}

$this->migrate(
        [
            '2013_10_11_081829_create_users_table',
        ]
    );
    $this->seed(UserTableSeeder::class);