条令\DBAL\Driver\PDOException:尝试在单元测试中使用工厂时找不到驱动程序

只要我不试图模仿DB对象,我的单元测试就可以正常工作。我创建了一个工厂,并试图在我的一个测试中使用它。然而,我不断地 a could not find driver error

这是我的测试课。

<?php
/**
 * Created by PhpStorm.
 */

namespace Tests\Unit\Helper\Results;

use Jobscan\Helper\Results\FormatHelper;
use Illuminate\Foundation\Testing\WithFaker;
use Illuminate\Foundation\Testing\RefreshDatabase;
use Illuminate\Foundation\Testing\WithoutMiddleware;
use Jobscan\Models\Document\Cv;
use Tests\TestCase;

class FormatHelperTest extends TestCase
{
    public function testFindingsForUploadedDocxResume_whenFontTypeIsNotStandard_resultFontTypeShowsNegativeResult()
    {
        $cv = factory(Cv::class)->create([
            'content' => "Testing Test test",
        ]);
        dd($cv);



 }
}

在我的phpunit测试中

<env name="DB_CONNECTION" value="test_db"/>
<env name="DB_DATABASE" value=":memory:"/>

这就是我一直犯的错误

 Caused by
 Doctrine\DBAL\Driver\PDOException: could not find driver

数据库.php文件

 // This database is ephemeral and used for testing purposes.
        'test_db' => [
            'driver'   => 'sqlite',
            'database' => ':memory:',
            'prefix'   => '',
        ],