Check Git LFS support

[christianspecht]

As suggested here:

• create a test repo with a large file
• set up Git LFS
• check whether SCM Backup is able to backup the repo, and if all large files are actually included in the backup

[christianspecht]

https://help.github.com/articles/duplicating-a-repository/#mirroring-a-repository-that-contains-git-large-file-storage-objects

[christianspecht]

Git LFS Specification

Additional thoughts:

Apparently, if you clone a repo with LFS objects and your local Git client has LFS not enabled, it just pulls the pointer files, but not the actual large file.

So when this happens while backing up with SCM Backup, it should detect if a repo contains LFS objects, and warn the user / throw an exception / not even start backing up (?) when LFS is not enabled in the local Git installation.

[DirkHeinke]

I just checked it, and git fetch seems to ignore LFS. So Backing up repositories with LFS currently ignores all files in LFS.

A git lfs fetch {url} after the fetch loads the LFS data. What would be the best way to integrate this feature?

[igor-gorjanc]

@christianspecht I have managed to make LFS working with the forked version. But it should be merged into this repo.

[christianspecht]

Sorry for the delay, I was on vacation first and then sick.

• Which forked version do you mean? The one from evolu1's PR, or my fork of it (which is also linked in the PR)?
• Did you make any additional code changes, or did it work as-is?
• We probably need documentation: If you read the conversation in evolu1's PR, you see that we weren't able to create a test repo with LFS files, backup it with the forked SCM Backup version and restore the LFS files. And as I already said there, I have zero experience with Git LFS and that didn't change in the meantime, I still have zero experience.