Use a dummy route defined in a test using a closure and apply to this dummy route your middleware.
Here in pest:
<?php
use App\Http\Middleware\MyMiddleware;
use Illuminate\Support\Facades\Route;
test('My Middleware', function () {
Route::get('my-test-middleware-route', fn() => 'ok')
->middleware([MyMiddleware::class]);
// Your logic here as an httpt test
test()->actingAs(User::factory()->create())
->get('/my-test-middleware-route')
........
});And of course, you can test with an other middleware:
Route::get('my-test-middleware-route', fn() => 'ok')
->middleware(['auth', MyMiddleware::class]);