Strange error in phpunit when I add RefreshDatabase to any test

Sounds like you are missing the str() helper https://laravel.com/docs/9.x/helpers#method-str

Are you sure your are extending the laravel testcase? use Tests\TestCase;

@sinnbeck Yes I just created a new laravel app with "laravel new footest", deleted the example unit test and left only the example feature test. artisan test works and phpunit works until I add "use RefreshDatabase"

Failing test

<?php

namespace Tests\Feature;

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

class ExampleTest extends TestCase
{
    use RefreshDatabase;

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

        $response->assertStatus(200);
    }
}

Tests/TestCase;

<?php

namespace Tests;

use Illuminate\Foundation\Testing\TestCase as BaseTestCase;

abstract class TestCase extends BaseTestCase
{
    use CreatesApplication;
}

The Error with stacktrace

There was 1 error:

1) Tests\Feature\ExampleTest::test_the_application_returns_a_successful_response
Error: Call to undefined function Illuminate\Console\View\Components\Mutators\str()

C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Console\View\Components\Mutators\EnsurePunctuation.php:15
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Console\View\Components\Component.php:89
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Console\View\Components\Line.php:44
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Console\View\Components\Info.php:18
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Console\View\Components\Factory.php:56
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Database\Console\Migrations\MigrateCommand.php:113
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Database\Console\Migrations\MigrateCommand.php:80
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Database\Migrations\Migrator.php:616
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Database\Console\Migrations\MigrateCommand.php:100
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Container\BoundMethod.php:36
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Container\Util.php:41
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Container\BoundMethod.php:93
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Container\BoundMethod.php:37
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Container\Container.php:651
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Console\Command.php:144
C:\Users\isimm\code\php\footest\vendor\symfony\console\Command\Command.php:308
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Console\Command.php:126
C:\Users\isimm\code\php\footest\vendor\symfony\console\Application.php:1002
C:\Users\isimm\code\php\footest\vendor\symfony\console\Application.php:299
C:\Users\isimm\code\php\footest\vendor\symfony\console\Application.php:171
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Console\Application.php:102
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Console\Application.php:194
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Foundation\Console\Kernel.php:263
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Testing\PendingCommand.php:296
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Testing\PendingCommand.php:475
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Foundation\Testing\Concerns\InteractsWithConsole.php:80
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Foundation\Testing\RefreshDatabase.php:47
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Foundation\Testing\RefreshDatabase.php:22
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Foundation\Testing\TestCase.php:123
C:\Users\isimm\code\php\footest\vendor\laravel\framework\src\Illuminate\Foundation\Testing\TestCase.php:92
C:\Users\isimm\code\php\laracasts\blog\vendor\phpunit\phpunit\src\TextUI\Command.php:143
C:\Users\isimm\code\php\laracasts\blog\vendor\phpunit\phpunit\src\TextUI\Command.php:96

ERRORS!
Tests: 1, Assertions: 0, Errors: 1.

Thanks