Interfaces with same name in separate files are combined

I have separate files that define private interfaces of the same name. By "private" I mean not exported.
dts-bundle puts them all in one file, where all the `IProps` interfaces combine into one mega-interface, which is bad news, since they're supposed to be different interfaces.

Do I have to give all my interfaces globally unique names?

(Using `outputAsModuleFolder: true`)