You would have to set a variable $GIT_EDITOR
in your ~/.bashrc
file to vi
. Alternatively, you can create a ~/.gitconfig
file with the values:
[core]
editor = vi
You can also place this file inside your local git repository so that it only affects that one particular project.
For other non-Git specific editors, there's also the variable $EDITOR
, which will work for other things in the same way (like sudoers configuration).
For reference:
https://git-scm.com/docs/git-config#Documentation/git-config.txt-coreeditor