Git with Multiple Identities

The global configuration file for git resides usually at ${HOME}/.gitconfig which is also the place where settings like git config user.name "John Doe" end up when you set them (only when applied outside of a git repository).

A while ago I was revisting my settings and decided to split the file into smaller chunks, which I placed in ${HOME}/.config/git and looks like this.

.
├── conf
│   ├── aliases.gitconfig
│   ├── settings.gitconfig
│   └── user.gitconfig
└── config

Any configuration file under conf gets added to config by include statements which bascially look like this:

[include]
    path = ./conf/user.gitconfig
    path = ./conf/settings.gitconfig
    path = ./conf/aliases.gitconfig
[init]
    defaultBranch = main
[fetch]
    prune = true

user.gitconfig is exactly what one would expect: the configuration of my default user name and email.

Mixed Identity Environments

Let's assume you have repositories that require different identities, e.g. a work repository vs a private repository.

One way to solve this issue would be to configure the identity in the repository like

git config user.name "John Doe"

which will then end up in <GITCHECKOUT>/.git/config and as you might already suspect that this gets easily tedious and is very error prone, but

One awesome feature of the git configuration files is that you can conditionally include config files, and this is what does the trick.

[include]
    path = ./conf/user.private.gitconfig
    path = ./conf/settings.gitconfig
    path = ./conf/aliases.gitconfig
[includeIf "gitdir:~/src/work/"]
    path = ./conf/user.work.gitconfig
[init]
    defaultBranch = main
[fetch]
    prune = true

By default, the configuration from user.private.gitconfig is always set. Once a repository is located inside ${HOME}/src/work/, my work identity is being included which has my work email address and the corresponding username configured.

This simple trick simplified my setup by leaps, as I have ${HOME}/.config/git available everywhere, but I usually tend to forget to set the correct email and username after cloning.

Furthermore, this is of course not limited to user name and email, but to any configuration parameter that can be used in .gitconfig.