Can gitconfig options be set conditionally?

No, Git config does not support checks or conditional statements. But your underlying shell probably does, so you can use something like:

[core]    editor = "if [[ $IS_REMOTE -eq 1 ]]; then ED='vim'; else ED='subl -n -w'; fi; $ED"

If you need to do something more complicated than that, you could just throw the shell code into a script, of course, like

[core]    editor = "my_edi_script.sh"

with my_edit_script.sh containing something like:

#!/bin/bashif [[ $IS_REMOTE -eq 1 ]]; then    ED="vim"else    ED="subl -n -w"fi$ED some argument or other

Edit: The my_edit_script.sh would have to be in the $PATH, of course :)

The [include] section learned by git-config in v1.7.9 gets you most of the way there.

While it doesn't let you write runtime conditionals, it does give you a framework for refactoring your ~/.gitconfig into several parts: the shared section, and the env-specific sections. After that, you can symlink something like ~/.gitconfig.local to the relevant env-specific config file, and include ~/.gitconfig.local from ~/.gitconfig.

The symlinking part can be scripted and done automatically as part of your dotfiles' init script.

From the command line, that include path can be added via:

git config --global include.path '~/.gitconfig.local'

I use the quotes above specifically to prevent the shell from expanding ~ to an absolute path.

That adds the following section to your ~/.gitconfig:

[include]    path = ~/.gitconfig.local

Here's a snippet from the git-scm book showing the general format:

[include]    path = /path/to/foo.inc ; include by absolute path    path = foo ; expand "foo" relative to the current file    path = ~/foo ; expand "foo" in your $HOME directory

You can conditionally include another Git config file based on your Git directory or branch in Git 2.13 and later.

Put your default configuration in file ~/.gitconfig as usual. At the end, conditionally include another configuration file:

[user]    email = john@personal.com    name = John McGehee# All work Git repositories are in a subdirectory of ~/work.# All other Git repositories are outside ~/work.[includeIf "gitdir:~/work/"]    path = .gitconfig.work

Then, in ~/.gitconfig.work add or override configuration values you want when using a repository located in ~/work or any subdirectory thereof:

[user]    email = john@work.com

You can observe the difference by changing to a Git directory under ~/work, and running:

git config user.email

Try the same command in a Git directory that is not under ~/work.