Laravel DatabaseMigrations產生錯誤：對空

Question

我想在我的單元測試運行DatabaseMigrations調用一個成員函數調用（），但我得到了以下錯誤：

1) VisitStaffPagesTest::testLogBills 
Error: Call to a member function call() on null 

/Users/x/Documents/office/vendor/laravel/framework/src/Illuminate/Foundation/Testing/ApplicationTrait.php:312 
/Users/x/Documents/office/vendor/laravel/framework/src/Illuminate/Foundation/Testing/DatabaseMigrations.php:12 

從DatabaseMigrations：

public function runDatabaseMigrations() 
{ 
    $this->artisan('migrate'); // This is line 12 

    $this->beforeApplicationDestroyed(function() { 
     $this->artisan('migrate:rollback'); 
    }); 
} 

從ApplicationTrait：

public function artisan($command, $parameters = []) 
{ 
    return $this->code = $this->app['Illuminate\Contracts\Console\Kernel']->call($command, $parameters); 
} 

任何想法，爲什麼我得到這個錯誤？

Answer 1

我最終解決這在我的TestCase.php文件中使用此代碼：

public function createApplication() 
{ 
    $app = require __DIR__.'/../bootstrap/app.php'; 

    $app->make(Illuminate\Contracts\Console\Kernel::class)->bootstrap(); 

    $this->code = $app['Illuminate\Contracts\Console\Kernel']->call('migrate'); 
    $this->beforeApplicationDestroyed(function() use ($app) { 
     $app['Illuminate\Contracts\Console\Kernel']->call('migrate:rollback'); 
    }); 

    return $app; 
} 

基本上我只是手動調用遷移和回滾。不知道它爲什麼會起作用，其他不起作用。

Answer 2

我想你應該從

public function createApplication() 
{ 
    $app = require __DIR__.'/../bootstrap/app.php'; 

    $app->make(Illuminate\Contracts\Console\Kernel::class)->bootstrap(); 

    return $app; 
} 

修改createApplication方法在TestCase：

public function createApplication() 
{ 
    $app = require __DIR__.'/../bootstrap/app.php'; 

    $app->make(Illuminate\Contracts\Console\Kernel::class)->bootstrap(); 

    $this->app = $app; // line added 

    return $app; 
}