As stated in the documentation:
When you receive such a project, you get the directories that contain submodules, but none of the files yet
I clone it with --recursive flag and git submodule init in it (?)
$ git clone --recursive git://path/to/repo.git
$ git submodule init
$ git submodule update
But I don't even get the directories. The .gitmodule file is there.
.gitmodule content:
[submodule "Alamofire"]
path = Alamofire
url = https://github.com/Alamofire/Alamofire.git
I use git version 2.11.0