Recursively cloning a git repo doesn't pull submodules

Question

I'd like to clone a git repo [1], which has a submodule defined in .gitmodules:

[submodule "PointInCircle"]
        path = PointInCircle
        url = https://github.com/midas-journal/midas-journal-843

Following these questions [2-4], I tried:

$ git clone --recursive https://github.com/midas-journal/midas-journal-851

If I understand submodules correctly, which I obviously don't, there should be a directory inside midas-journal-851 called PointInCircle with the second repo cloned into it. However, no PointInCircle directory is created and as far as I can tell the code isn't cloned anywhere. For good measure, I also tried...

$ git submodule init
$ git submodule update

...as well as...

$ git submodule update --init --recursive

...and...

$ git submodule foreach --recursive git submodule update --init

...in the cloned directory. Each command runs without printing anything to the console, and I don't see any changes in the directory.

Any ideas what I'm doing wrong?

[1] https://github.com/midas-journal/midas-journal-851
[2] Cloning a git repo with all submodules
[3] How to `git clone` including submodules?
[4] 'git submodule update --init --recursive' VS 'git submodule foreach --recursive git submodule update --init'

Answer 1

Any ideas what I'm doing wrong?

You're not doing anything wrong. That repository's submodule is only partially configured.

Submodules are defined by two things:

Submodules are composed from a so-called gitlink tree entry in the main repository that refers to a particular commit object within the inner repository that is completely separate. A record in the .gitmodules ... file at the root of the source tree assigns a logical name to the submodule and describes the default URL the submodule shall be cloned from.

This repository contains a .gitmodules file, but no gitlink objects.

GitHub displays proper submodules with a grey folder icon, which is absent from this repository:

Since the faulty .gitmodules file only contains a single entry, in your case I recommend

1. deleting the .gitmodules file,

   git rm .gitmodules
   

2. adding the submodule properly,

   git submodule add https://github.com/midas-journal/midas-journal-843 PointInCircle
   

3. and committing.

   git commit -m "Fix PointInCircle submodule"
   

The output from git commit should show PointInCircle being added with mode 160000 (indicating a gitlink), and your repository should now be properly configured. Use git submodule status to be sure:

$ git submodule status
9bc2651367f8cc5f47ac5f6c708db2f9a71d8fd8 PointInCircle (heads/master)

You might want to open a pull request to the parent repository with your fix, but since it only contains a single commit from three years ago I suspect that it is abandoned.