yii2-swiftmailer/tests/TestCase.php

<?php

namespace yiiunit\extensions\swiftmailer;

use yii\helpers\ArrayHelper;

abstract class TestCase extends \PHPUnit\Framework\TestCase
{
    /**
     * Clean up after test.
     * By default the application created with [[mockApplication]] will be destroyed.
     */
    protected function tearDown()
    {
        parent::tearDown();
        $this->destroyApplication();
    }

    /**
     * Populates Yii::$app with a new application
     * The application will be destroyed on tearDown() automatically.
     * @param array $config The application configuration, if needed
     * @param string $appClass name of the application class to create
     */
    protected function mockApplication($config = [], $appClass = '\yii\console\Application')
    {
        new $appClass(ArrayHelper::merge([
            'id' => 'testapp',
            'basePath' => __DIR__,
            'vendorPath' => $this->getVendorPath(),
        ], $config));
    }

    protected function getVendorPath()
    {
        $vendor = dirname(dirname(__DIR__)) . '/vendor';
        if (!is_dir($vendor)) {
            $vendor = dirname(dirname(dirname(dirname(__DIR__))));
        }
        return $vendor;
    }

    /**
     * Destroys application in Yii::$app by setting it to null.
     */
    protected function destroyApplication()
    {
        \Yii::$app = null;
    }
}