Setting autochdir and using Fzf breaks Fugitive commit capability

[sim590]

• [x] I have read through https://github.com/junegunn/fzf.vim/blob/master/README.md
• [x] I have read through https://github.com/junegunn/fzf/blob/master/README-VIM.md
• [ ] I have read through the manual page of fzf (man fzf)
• [x] I have earched through the existing issues

Problem

Using FZF to navigate to a file under subdirectory with the setting autochdir breaks directory dependant functionalities such as vim-fugitive.

To reproduce

$ mkdir /tmp && cd /tmp && git init
$ mkdir tata && echo "some stuff in this file" > tata/tutu # this is in a subdirectory
$ vim

Then, in Vim, use this configuration:

call plug#begin('~/.vim/plugged')
Plug 'tpope/vim-fugitive'
Plug 'junegunn/fzf'
Plug 'junegunn/fzf.vim'
call plug#end()

filetype plugin indent on

set autochdir

and do the following:

:Files " select tata/tutu
:Gstatus
:Gcommit

Note that one can take the time to stage the files before running the last :Gcommit command while it does not have any incident on the following result which is an error one should not get at this point:

fatal: This operation must be run in a work tree

Important remarks

• Unsetting the autochdir option does go around the problem, i.e. that you can do a commit with the :Gstatus window without issue;
• Opening the file using means other than Fzf such as :e or even using the :Startify command from the [vim-startify][] plugin won't trigger this issue.
• This issue happened with Ctrl-p as well before I switched to Fzf and I suspect that both projects are independantly responsible.
• This issue could be linked to https://github.com/tpope/vim-fugitive/issues/1195. Note that I may not have realized back when I commented on this last thread, but it seems like using either ctrl-p or Fzf to change file ended up causing the issue.
• Running :pwd inside the file window or in the :Gstatus window, in both cases, gives a sensible result. In the former case, you'd get $ROOT/tata and in the latter, you get $ROOT/.git.

[sim590]

Note that while I did mention that Ctrl-p would trigger the issue, the procedure to reproduce may not be so similar. Simply opening the file using Ctrl-p doesn't seem to trigger the issue, but that is not of big importance regarding the problem with Fzf.

[wshanks]

I opened an issue in the main fzf repo because I think the issue is in its vim plugin (which this vim plugin uses).