Git is deleting an ignored file when i switch branches

Question

I have one branch (let's call it B) that ignores a certain file, which isn't ignored in some other branches (eg branch A). When i switch from branch B to branch A, then back to B again, the file has been deleted.

Is this normal? I can sort of see how it would happen, in the sense that branch B thinks it's not there, and branch A thinks that it is, so when i go back to B it 'tidies it away'. But it's kind of annoying.

Any suggestions?

Answer 1

Since the only viable solution is to track the file 'f' at all times, you could add, only in branch B, a smudge/clean process with a gitattributes filter driver:

When checkouting branch B:

• the smudge process would change:

  • save the content of f in a temp file
  • replace the content of f with one fbis file (a tracked file which would contain, for branch B, the "B content of f")

• the clean process would:

  • save f content (as modified in B) in fbis (fbis gets committed with f modifications in branch B)
  • restore f content (with the temp file), meaning f is not committed (ignored in B)

You can add, still in branch B, a custom merge driver which will protect fbis in case of merges from other branches to B:
the merge driver will always keep B version of fbis content, making sure the ignored file f gets back its content whenever branch B is checked-out.

Since those drivers (filter and merge) are not committed in other branches, the file 'f' is committed in other branches with all its modifications.
In branch B, its content will never change, and yet the "local modifications" made to f are still restored whenever B is checked-out.

If that content restoration is not needed, you don't need to manage fbis.
Just keep the filter driver and you will be sure that whatever modification you do to f in branch B, those changes will never be committed, effectively ignoring f content.