Delete branches with no upstream

git-branch-cleanup

#!/bin/bash
#
# Usage: Run `git-branch-cleanup.sh' in a git repository
#    OR `git branch-cleanup' if the script is in your ${PATH}
#


# git_branch_delete
#
# Delete a given branch if not the current branch
# Actually, we could just run git branch -d 'branch', and let that handle
# errors. Meh, I already did this anyway.
#
function git_branch_delete # branchname
{
    local branch="$1" current=$( git rev-parse --abbrev-ref HEAD ) commit="$2"

    # Assert that a branch name is given
    [ -z "${branch}" ] && echo "Usage: git_branch_delete <branchname>" && return 1

    # Assert that we can read out the current branch
    [ -z "${current}" ] && echo "Error: No selected branch" && return 2

    # Check if we're trying to delete the current branch
    if [ "${branch}" = "${current}"  ]; then
        echo "Error: Currently on branch '${current}', can't delete"
        return 3
    fi

    # Actually delete
    if [ -n "${commit}" ]; then
        echo "Deleting branch '${branch}'"
        git branch -d "${branch}"
        return $?
    fi

    echo "git branch -d '${branch}'"

    return 0
}


# An array of local branches with missing upstream branch
noremote=()
#
# Gather branches without upstream
#
while read local remote
do

    [ -z "$local" ] && continue  # This is probably an error

    # No remote? If so, keep track of the local branch name
    [ -z "$remote" ] && noremote+=( "${local}" ) && continue

    # Unable to connect local+remote? If so, keep track of local branch name
    git rev-list --left-right ${local}...${remote} --quiet || noremote+=( "${local}" )

done < <( git for-each-ref --format="%(refname:short) %(upstream:short)" refs/heads )

echo "noremote: ${noremote[@]}"

# Quit if we have no local branches with missing upstream branch
[ ${#noremote[@]} -eq 0 ] && echo "No branches with missing upstream" && exit 0

# List branches
echo "Branches without upstream:"
for missing in ${noremote[@]}; do
    echo "  ${missing}"
done
echo ""

# We don't commit yet, so
echo "To delete, run..."

# List commands to delete local branch.
for missing in ${noremote[@]}; do
    git_branch_delete "${missing}"  # Add "commit" arg here to actually delete
done


# Quit if the current branch is in the array of found brances
#for missing in ${noremote[@]}; do
    #[ "${missing}" != "${current}" ] && continue
    #echo "Currently on branch '${current}', can't delete."
    #exit 1
#done

# TODO: We should list the branches, and ask interactively if we want to delete
#       them.
#       If [y], delete branches
#       If [n], list delete command for each branch
#
#       If implemented, we should also consider arguments (e.g. non-interactive
#       flags to delete or list commands).