Git attributes affecting submodule

Question

No: if you want to define a content filter driver (smudge/clean script) applied during the checkout of a submodule, it needs to be defined in a .gitattributes stored within the submodule repo.

BUT: if you don't want to add a .gitattributes to the submodule repo (because, for instance, you don't own that repo, you are only including it and want to apply a filter which makes sense in your context), what you can do is:

initialize the submodule (git submodule init or even git submodule update --init):
That will create in your parent repo a .git/modules/yourSubmodule folder
copy in .git/modules/yourSubmodule/info/attributes the attributes you want to declare for certain files (here, fore instance, all ruby files)
```
*.rb filter=yourFilter
```

That will play the role of the .gitattributes (still valid only for the submodule, but defined and stored in your parent_repo/.git/modules/)
That way, you can define attributes for a submodule without having to add a .gitattributes within the submodule repo itself.

It isn't exactly a '.gitattributes' of your parent repo: it is something you add after initializing a submodule, within the .git/modules folder of your parent repo.
You can store the content of that "gitattributes" as a regular file in your parent repo, but you will have to write a script able to initialize submodule and copy that file as a .git/modules/yourSubmodule/info/attributes file.
I have done so in my project: see this installation script as an example.

modify .git/modules/yourSubmodule/config in order to declare a smudge or clean filter referencing that script.
```
[filter "yourFiler"]
    smudge= yourScript1 %f
    clean = yourScript2 %f
```

Then, providing you did already update your submodule (git submodule update), running a

cd parentRepo/yourSubmodule
git checkout HEAD -- .

That will trigger your filter scripts for that submodule