Why doesn't whereIn recognize the passed array?

Question

Laravel

Hello, tell me why when I try to filter by related models and pass an array of values, Undefined variable crashes: request

if ($request->size) {
            $productsQuery->whereHas('attributes', function($q) {
               $q->whereIn('size', $request->size);
           })->get();
        }

Although if you do this, then everything is OK
$productsQuery->whereIn('color', $request->color);

Answer 1

$productsQuery->whereHas('attributes', function($q) use ($request) {
               $q->whereIn('size', $request->size);
           })->get();