Git: removing feature branches on merge

When working with feature branches, stale branches pile up over time. It's best to remove them right after merge, locally and on the remote, but it is a little tedious: you need to remember it, and perform the few steps manually each time.

Enter Git hooks. The folks at Liquid Light have built a little post-merge hook that will delete a feature branch on confirmation Show archive.org snapshot .

Quick aside: Git hooks location

Git hooks are normally stored in the current repository, at .git/hooks/. They are not checked in and will not be shared with others.

If you prefer to manage your hooks globally, i.e. have a single set of hooks that applies to all your repositories, you can change the Git hooks location Show archive.org snapshot : git config --global core.hooksPath /path/to/my/centralized/hooks.

The post-merge hook

Create a post-merge file in your hooks directory (see above). Paste this:

#!/bin/bash
exec < /dev/tty

# Get the current branch name
branch_name=$(git branch --show-current)

# Get the name of the branch that was just merged
reflog_message=$(git reflog -1)
merged_branch_name=$(echo $reflog_message | cut -d" " -f 4 | sed "s/://")

if [[ "$merged_branch_name" == "@{-1}" ]]; then
  # Somebody merged "-", the previous branch. Resolve it to the actual branch
  # name.
  merged_branch_name=$(git name-rev @{-1} --name-only)
fi

# Don't offer branch deletion for some branch names
if [[ "$merged_branch_name" =~ ^(master|main|production|Fast-forward)$ ]]; then
    exit 0
fi

# Begin output
echo " "
echo "> You have just merged the branch \"$merged_branch_name\" into \"$branch_name\". "

# Ask the question                                                              
read -p "> Do you want to push \"$branch_name\" + delete the \"$merged_branch_name\" branch? (y/N) " answer
                                                                                
if [[ "$answer" == "y" ]]; then                                                 
    git push                                                                    

    # Delete the local branch
    git branch -d $merged_branch_name

    echo "> Deleting remote branch ..."
    git push origin --delete $merged_branch_name
    exit 1
else
    echo "x Did not delete the \"$merged_branch_name\" branch."
fi

Save the file and make it executable: chmod +x path/to/post-merge

Now, after merging a branch, you will be asked if you would like to have the branch deleted:

$ git merge ds/foo
Updating 338e82e38..2d4269c81
Fast-forward
 foo | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 foo
 
> You have just merged the branch "ds/foo" into "master". 
> Do you want to push "master" + delete the "ds/foo" branch? (y/N) y
To github.com
   abc123..def456 master -> master
Deleted branch ds/foo (was 2d4269c81).
Deleting remote branch ...
- [deleted] ds/foo