Cleaning up Git repos

Deleting old remote branches

If you have a repository that’s been around for long enough, you probably have a fair number of “stray branches”: deadends, false starts, orphans, etc. Let’s clean up all of the remote branches that haven’t been touched in the last 6 months:

for k in $(git branch -r | grep -E -v '>|master|prod'); do
  if [ -z "$(git log -1 --since='6 months ago' -s $k)" ]; then
    git push origin --delete $(cut -d"/" -f2- <<< "$k");

Walking through the various steps:

  1. git branch -r lists all remote branches
  2. grep -E -v '>|master|prod' filters that list of branches, removing any that have > (e.g. origin/HEAD -> origin/master), master (e.g. origin/master), or prod (e.g. origin/prod) in their names.
  3. Iterating over each of these branches (as $k), git log -1 --since='6 months ago' -s $k checks if the branch has been commited to in the last 6 months (you could obviously set the timeframe to whatever suited your needs).
  4. cut -d"/" -f2- <<< "$k") trims a branch string like origin/feature/some_branch to a string like feature/some_branch.
  5. Finally git push origin --delete $(...) removes that branch from the remote repository.

Deleting already-merged remote branches

You may also find yourself needing to remove remote branches that have also already been merged to master.

git branch -r --merged origin/master
| grep -E -v '>|master|prod'
| cut -d"/" -f2-
| xargs git push origin --delete

Here we see many of the same basic sub-commands we used before. There is, however, one note-worthy difference. We specify the specific branch we want to check whether the remote branches have been merged into by specifying origin/master. This ensures that only remote branches that have been merged into remote master are passed to the next sub-command.

Deleting already-merged local branches

Finally, if you need to clean up your local repository, you can prune the local branches that have already been merged into master in a similar way:

git branch -d $(git branch --merged master | grep -E -v '\*|master|prod')

A word of warning though: have local copies of these branches somewhere, just in case you delete a branch you want back at some point ;)