工匠的随机错误

Question

每当我启动php artisan时，即使我没有修改文件，我也会在一段时间后发现随机错误。这些错误对我来说也没有意义。例如：

PHP Parse error:  syntax error, unexpected '++' (T_INC), expecting '(' in /.../app/Providers/AuthServiceProvider.php on line 32

PHP Parse error:  syntax error, unexpected '?' in /.../app/Providers/AuthServiceProvider.php on line 32

PHP Parse error:  syntax error, unexpected '' in /.../app/Providers/AuthServiceProvider.php on line 32

AuthServiceProvider.php：

<?php

namespace App\Providers;

use Illuminate\Contracts\Auth\Access\Gate as GateContract;
use Illuminate\Foundation\Support\Providers\AuthServiceProvider as ServiceProvider;

class AuthServiceProvider extends ServiceProvider
{
    /**
     * The policy mappings for the application.
     *
     * @var array
     */
    protected $policies = [
        'App\Model' => 'App\Policies\ModelPolicy',
    ];

    /**
     * Register any application authentication / authorization services.
     *
     * @param  \Illuminate\Contracts\Auth\Access\Gate  $gate
     * @return void
     */
    public function boot(GateContract $gate)
    {
        $this->registerPolicies($gate);

        //
    }
}

第32行是文件末尾的换行符。

有时工匠成功运作（再次没有我更改任何文件）。可能会发生什么？

PHP 5.6版，Laravel 5.2.45