src/UploadHandlerBuilder.php
public function naming($namer)
    {
        if ($namer instanceof \Closure) {
            $namer = new ClosureNamer($namer);
        }
        $this->namer = $namer;
        return $this;
    }
public function naming($namer)
    {
        if ($namer instanceof \Closure) {
            $namer = new ClosureNamer($namer);
        }
        $this->namer = $namer;
        return $this;
    }
Sets namer.

@param \Closure|NamerInterface $namer
@return $this