file_unmanaged_copy - Any service alternatives? The functionality of the file_unmanaged_copy is exactly what I need. The only problem is: it's a global function which uses static service calls.
Since I need to unit test my class (and not to mention how I dislike hidden dependencies coming from global functions) I can't use it.

Am working with D8 since the very beginning, but am failed to find any OO alternatives. Has anyone faced the same situation? Any "Best-practises" or workarounds?
This changed in Drupal 8.7.0
See https://www.drupal.org/node/3006851
try {
  \Drupal::service('file_system')-&gt;copy($source, $destination, $replace);
} 
catch (\Drupal\Core\File\Exception\FileException $e) {
    // Log or set message or doing something else.
}