Vim Configuration Files by Directory

I have Vim line numbers enabled (:set nu) as a default, but I was working on a project recently where the line numbers weren't helpful. I wanted to disable them in that directory only, without changing my default setting.

One way to do this is to enable a local Vim configuration file. Here's how you do that:

" ~/.vimrc
set exrc

This enables the reading of .vimrc in the current directory.

Caveat: you should also add the following:

" ~/.vimrc
set secure

When this setting is enabled, :autocmd, shell, and write commands are not allowed in your local .vimrc.

Enabling local Vim configurations give a lot of power to any local configuration file. For instance, you could clone a Git repo with a checked-in .vimrc, and if you open Vim in that directory, any commands in that configuration will be executed. Use with caution.

More info:

:help 'exrc'
:help 'secure'

h/t Josh Branchaud