I am working my way through a Joomla 4 component tutorial. I have setup Visual Studio Code's Intelephense to be able to find Joomla classes using includepath. That seems to be working fine for the first php file in the tutorial, "script.php" (for example, VS Code can find
However, the second php file, "provider.php", defines a class that derives from
Joomla\DI\ServiceProviderInterface. Intelephense can't seem to find where that class is defined and, after looking through my local instance of Joomla's source code, neither can I.
Where is Joomla\DI\ServiceProviderInterface defined?
And if such dependencies are not part of the Joomla source code, where does Joomla get them from at runtime?