git-crypt support?

[MinmoTech]

If I try to use :Gdiffsplit in a project that is encrypted with git-crypt, it always tries to diff with an encrypted file.

If i do a git diff or a git difftool on the commandline it works properly.
Is it possible to configure fugitive to work properly with git crypt?

[Parasrah]

this seems to be a duplicate of #1508, albeit with more info

[tpope]

We currently use git cat-file to populate the diff buffer. If you can provide a ore appropriate command to swap in it's possible we could support it.

[YorikSar]

@tpope Since git 2.11 (released in 2016) you can pass --filter instead of blob to git cat-file and it will process it with filters if applicable, including git-crypt. I think it should be enough replacing blob with --filter on lines 2112 and 2955 in autoload/fugitive.vim, but I don't really know if it will break smith else.

If you have to support older Git, maybe add an option for that? Like "supported Git version" or smth.

[tpope]

The only breakage I can think of is that for the second case, the rev is not guaranteed to contain a :path. To address the path issue and the version issue in one go, try rev =~# ':' && fugitive#GitVersion(2, 11) ? '--filters' : 'blob'.

Please try the change out locally for a week or so and report back on your experience.

[YorikSar]

Thanks for the direction. I've created commit YorikSar/vim-fugitive@58c6f2f and will test it for some time (I don't use git-crypt a lot, so it'll take about a month to be sure), then will create a pull request. Feel free to comment on that commit in the mean time.

[tpope]

Limitations:

• staging/unstaging separate hunks (ala "git add -p") doesn't work, because "git apply" doesn't know about filters, same as "git add -p".

Is this a limitation related to your patch, or just of using git-crypt with Fugitive in general?

[YorikSar]

It's a limitation of the git-crypt in general. git add -p (even without vim-fugitive) always complains that the encrypted file is binary and exits.

[tpope]

Alright let's ditch that from the commit message before sending a PR then just to minimize confusion.

And on that note, send a PR whenever, a release isn't imminent so your light testing is probably good enough.

[YorikSar]

Ok, you're the boss! Created #1837.