How to get main branch name from command-line/terminal?
I know that the main branch is called master by default, however one can rename it to anything they want.
PS—It would be nice to get the name of the local and remote main branch.
Edit: What I call main branch others might call default branch or stable branch. It’s the one into which you (should) merge everything (stable/working) into.
I have no deep knowledge of git, however, in git, there is usually {remote}/HEAD, e.g. origin/HEAD. Here’s an excerpt from the man page of git remote:
set-head
Sets or deletes the default branch (i.e. the target of the
symbolic-ref refs/remotes/<name>/HEAD) for the named remote.
Having a default branch for a remote is not required, but allows
the name of the remote to be specified in lieu of a specific
branch. For example, if the default branch for origin is set to
master, then origin may be specified wherever you would normally
specify origin/master.
From this I understand that the {remote}/HEAD is the main/default branch of the {remote}. One could get the name of the branch using this (does anyone know a better/plumbing command?):
git branch -r | grep -Po 'HEAD -> \K.*$'
origin/master
When one wants to get the local main/default branch, there usually is no HEAD branch, however usually there’s one and only branch that tracks the {remote}/HEAD, which name we can get using (again, there surely is a better command):
git branch -vv | grep -Po "^[\s\*]*\K[^\s]*(?=.*$(git branch -rl '*/HEAD' | grep -o '[^ ]\+$'))"
master
Of course, one need to set-head if it is not already set, in order to have a ‘HEAD/master/main branch’ in the output of git remote -r. Therefore, we need to run the following command once prior to using the above commands (thanks for pointing this out @pixelbrackets).
git remote set-head origin -a
Update:
Recently, I wanted to get some more information (some commands I’ve got from here):
# Get currently checked out local branch name
git rev-parse --abbrev-ref HEAD
# Output: branch
# Get remote branch name that is tracked by currently checked out local branch
git for-each-ref --format='%(upstream:short)' "$(git symbolic-ref -q HEAD)"
# Output: origin/branch
# Get local main branch name
git branch -vv | grep -Po \
"^[\s\*]*\K[^\s]*(?=.*$(git branch -rl '*/HEAD' | grep -o '[^ ]\+$'))"
# Output: master
# Get remote branch name that is tracked by local main branch (AKA the remote HEAD branch)
git branch -r | grep -Po 'HEAD -> \K.*$'
# Output: origin/master
If you assume that the main branch will either be called master or main, here is what I do to quickly detect the main branch name in a local repository:
git_main_branch () {
git branch | cut -c 3- | grep -E '^master$|^main$'
}
Then other commands I have that need to know the main branch name can use it. For example I have gc-m which stands for "git checkout main branch":
alias gc='git checkout '
alias gc-m='gc $(git_main_branch)'
you can also use something like this:
alias gc-m='git checkout `git branch -rl "*/HEAD" | rev | cut -d/ -f1 | rev`'
you probably want to use this command git branch -r, -r is for list remote branches only, if you want to list both uses -a.
Normally the master branch point to origin/HEAD something like this origin/HEAD -> origin/master
