Testing Laravel-Excel download - laravel

Question

I'm using following package: https://github.com/Maatwebsite/Laravel-Excel at version 2 with Laravel version 5.1
I've have got controller method with following code:
....
return Excel::create('List', function($excel) use ($list)
{
$excel->sheet('List', function($sheet) use ($list)
{
$sheet->fromModel($list);
});
})
->download('csv');
and simple test like this:
$this->call('GET', 'route/to/csv', [
'param' => 'value',
]);
$this->dump();
Above test outputs [ERROR]: Headers already sent from this line of the package.
Controller method works fine, but can't test it.
I've tried to run phpunit with --stderr param. In that case, no error is thrown, but it just dumps output of CSV file to console and exits.
I've also tried to run test with #runInSeparateProcess annotation and got errors like:
PHPUnit_Framework_Exception: PHP Notice: Constant LARAVEL_START already defined in bootstrap/autoload.php on line 3
....
PHP Fatal error: Uncaught exception 'ReflectionException' with message 'Class env does not exist' in vendor/laravel/framework/src/Illuminate/Container/Container.php:736
Could this be a bug in Laravel-Excel package or I'm testing it wrong?

Answer 1

Thats because the way the download method works in laravel-excel is by setting headers. You want to avoid that, and instead do all the work your self by returning laravel Responses.
Try this instead:
$file = Excel::create('List', function($excel) use ($list) {
$excel->sheet('List', function($sheet) use ($list)
{
$sheet->fromModel($list);
});
})->string('xls');
return new Response($file, 200, [
'Content-Type' => 'application/vnd.ms-excel; charset=UTF-8',
'Content-Disposition' => 'attachment; filename="' . $file->filename . '.' . $file->ext . '"',
'Expires' => 'Mon, 26 Jul 1997 05:00:00 GMT', // Date in the past
'Last-Modified' => Carbon::now()->format('D, d M Y H:i:s'),
'Cache-Control' => 'cache, must-revalidate',
'Pragma' => 'public',
]);
The key difference is to use the string() method which will return the binary data for the excel file and allows you to pass it as the data for a response.