Corrupted git tree?

Question

I'm having big problems with a git repository on my local machine.

I modified a file, ran git status and the file appeared as modified. I added the file using git add . and it worked as usual. But when i was about to commit the changes, i got the following error:

error: garbage at end of loose object 'e91ce852822d32e380ed7ddd04c93066e3c600ea'
fatal: object e91ce852822d32e380ed7ddd04c93066e3c600ea is corrupted

By running git cat-file -t e91ce852822d32e380ed7ddd04c93066e3c600ea, i can see that the object is a tree.

I've seen several solutions on how to repair a corrupt blob or commit, but this is a tree, and I can't find an answer on what could have went wrong, or how to fix it.

Any help appreciated :)

Answer 1

If your git repo is synchronised with an external ressource (Github) and if any solution didn't work, you can re-init your repo

what I've done :

# copy the corrupted .git dir
mv -f .git .gitback
git init
# keep your config file
cp .gitback/config .git/config
# load objects
git pull

It worked. Obviously, it's not a great solution, but it can help

Answer 2

What could have gone wrong is hard to tell, and depends on your Git version and environment.
For example, in the old days, there was a zlib issue with git1.5.1 triggering that kind of message due to a legacyheaders = false settings.

As for restoring a tree from loose objects, this SO answer "How to recover Git objects damaged by hard disk failure?" illustrates a way to do it, after that a git fsck --full (as Mark Rushakoff mentions in the comment) has been performed.

git cat-file -t 6c8cae4994b5ec7891ccb1527d30634997a978ee

and check the type of the object.

If the type is tree: you could use 'git ls-tree' to recover the tree from previous backups; then 'git mktree' to write it again in your current repository.

But that suppose finding those objects either in older packs or in repository backups.