Pruning old Git branches
Here’s a quick tip for Git users: if you want to delete every local branch that’s already been merged into master, you can run this command:
$git branch --merged master | egrep -v "(^\*|master|dev)" | xargs git branch --delete
A quick breakdown:
git branch --merged mastergives us a list of branches “whose tips are reachable from the specified commit” — any branch whose final commit has been merged into master. If your main branch has a different name, use that instead of master.
That gets piped to
egrep -v, which excludes any lines which match the pattern. In this case, the pattern filters out branches whose name ends in master or dev. You should adapt this for any long-lived branches in your repo.
Finally, any branches which remain are passed via
git branch --delete, which deletes the branch.
I originally got the command from a Stack Overflow answer, although I tweaked it when I read the documentation, to more closely match my use case.
If you want to see what branches this will delete without committing to it, run everything before the second pipe — not the
xargs bit at the end.
The other command I often use is this one:
$git fetch origin --prune
If a branch has been deleted in the origin remote, and you had a local branch which was tracking it, the local branch gets deleted as well.
For example: suppose you had a branch called new-feature. You push the branch to GitHub, open a pull request, and later the branch gets merged and deleted through the GitHub web interface. When you do your next
--prune, it’ll clean up the local branch new-feature.
Git branches are very cheap — usually a single file that references a commit hash — so deleting branches won’t save disk space or improve performance. I like to keep my repos neat and tidy, and not have a long branch list to scroll through, which is why I do this. If a long branch list doesn’t bother you, then you can ignore these commands.