hook_module_preinstall($module) Perform necessary actions before a module is installed.

public ModuleHandlerInterface::getName($module)

Filters a RecursiveDirectoryIterator to discover extensions. To ensure the best possible performance for extension discovery, this filter implementation

public ModuleHandlerInterface::loadInclude($module

A list of all currently available themes. Type:

public ModuleHandler::addModule($name, $path)

public ModuleHandlerInterface::getModule($name)

public ModuleHandlerInterface::writeCache()

The site path. Type: string File core/lib/Drupal/Co

public ThemeHandlerInterface::rebuildThemeData()