file/tests/CreatesApplication.php

<?php

namespace Tests;

use App\Providers\SettingServiceProvider;
use Illuminate\Contracts\Console\Kernel;
use Illuminate\Support\ServiceProvider;

trait CreatesApplication
{
    /**
     * Creates the application.
     *
     * @return \Illuminate\Foundation\Application
     */
    public function createApplication()
    {
        $app = require __DIR__.'/../bootstrap/app.php';

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

        $app->id = 0;

        app()->bind('nextId', fn() => $this->nextId());

        app()->instance(SettingServiceProvider::class, null);
        app()->register(FakeSettingServiceProvider::class);


        return $app;
    }

    private function nextId(): int
    {
        $id = $this->app->id;
        $id++;
        $this->app->id = $id;

        return $id;
    }
}

class FakeSettingServiceProvider extends ServiceProvider {

    function boot() {
        $this->app->bind('settings', function() {
           return json_decode(file_get_contents(base_path('settings.json')), true);
        });
    }
}