public function addSourceFile(string $filename) : void
    {
        $divisionData = $this->loadFile($filename);

        $this->divisionDataValidator->validate($divisionData, $filename, $this->allDivisions, false);

        $this->collection->addDivision(
            $this->divisionFactory->build(
                $divisionData,
                $filename,
                false
            )
        );
    }