Craft\ImportService::columns PHP Method

    public function columns($file)
    {
        // Open CSV file
        $data = $this->_open($file);
        // Return only column names
        return array_shift($data);
    }

 /**
  * @covers ::columns
  */
 public function testColumnsShouldReturnColumnRow()
 {
     $file = __DIR__ . '/tst_csv.csv';
     $expectedColumns = array('column1', 'column2', 'column3', 'column4', 'column5');
     $this->setMockAssetsService($file);
     $service = new ImportService();
     $result = $service->columns($file);
     $this->assertSame($expectedColumns, $result);
 }