How are the «generated/medatata» files generated in Magento 2.2?

1. Magento\Setup\Module\Di\App\Task\Operation\Area::doOperation()

Details: How does Magento\Setup\Module\Di\App\Task\Operation\Area::doOperation() work?

2. Magento\Setup\Module\Di\Compiler\Config\Writer\Filesystem::write()

3. Magento\Framework\App\Filesystem\DirectoryList::GENERATED_METADATA

See also: