git-clean-branches

#!/usr/bin/env python3

import argparse
import re
import subprocess
from sys import exit

parser = argparse.ArgumentParser(
    description="Remove local branches, which are no longer available in the remote"
)
parser.add_argument("--prune", action="store_true", help="Remove branches")
parser.add_argument("--force", action="store_true", help="Force deletion")
parser.add_argument("--remote", default="origin", help="Remote name (default: origin)")
parser.add_argument("--verbose", action="store_true", help="Verbose output")
args = parser.parse_args()


def find_local_branches():
    branches = subprocess.check_output(["git", "branch"]).decode("utf-8")
    correct_branches = []
    for line in branches.splitlines():
        # take out the active branch, we are only intersted in the name of the
        # branch
        branch_name = re.sub(r"\*", "", line).strip()

        # find out what is the remote of the branch
        try:
            remoteName = subprocess.check_output(
                ["git", "config", "--get", "branch.%s.remote" % branch_name]
            ).decode("utf-8")
        except Exception as e:
            # Branch has no config"
            remoteName = ""

        remoteName = remoteName.strip()

        if "%s" % remoteName == args.remote:
            correct_branches.append(branch_name)

    return correct_branches


def find_remote_branches():
    branches = subprocess.check_output(["git", "branch", "-r"]).decode("utf-8")
    correct_branches = []

    for line in branches.splitlines():
        branch_name = line.strip()
        result = re.search(r"%s/([^\s]*)" % args.remote, branch_name)
        if result:
            correct_branches.append(result.group(1))

    return correct_branches


def find_live_branches():
    correct_branches = []

    try:
        branches = subprocess.check_output(
            ["git", "ls-remote", "-h", args.remote]
        ).decode("utf-8")
    except Exception as e:
        # TODO: test that this is error 128

        return None

    for line in branches.splitlines():
        branch_name = line.strip()
        result = re.search(r"refs/heads/([^\s]*)", branch_name)

        if result:
            correct_branches.append(result.group(1))

    return correct_branches


def delete_branches(branches):
    broken = []

    if not branches:
        print("No removed branches found")
        return

    if not args.prune:
        print("Found removed branches:")

    for branch_name in branches:
        if args.prune:
            if args.verbose:
                print("Removing %s" % branch_name)

            if args.force:
                deleteFlag = "-D"
            else:
                deleteFlag = "-d"

            return_code = subprocess.call(
                ["git", "branch", deleteFlag, branch_name], stderr=subprocess.DEVNULL
            )
            if return_code != 0:
                if args.verbose:
                    print("ERROR: Unable to remove branch")
                broken.append(branch_name)
        else:
            print("  - %s" % branch_name)

    if broken:
        print("Not all branches are removed (try --force):")

        for branch_name in broken:
            print("  - %s" % branch_name)

    elif args.prune:
        pass

    else:
        print("INFO: To remove all found branches use --prune flag")


def analyze_live_and_remote(live_branches, remote_branches):
    if live_branches == None:
        return remote_branches

    notFound = []

    for branch_name in remote_branches:
        if branch_name != "HEAD":
            try:
                index = live_branches.index(branch_name)
            except ValueError:
                notFound.append(branch_name)

    if notFound:
        print('WARNING: Your git repository is outdated, please run "git fetch -p"')
        print("         Following branches are not pruned:")

        for name in notFound:
            print("  - %s" % name)

    return live_branches


def find_to_remove(local=[], remote=[]):
    will_remove = []

    for branch_name in local_branches:
        try:
            index = remote_branches.index(branch_name)
        except ValueError:
            will_remove.append(branch_name)

    return will_remove


try:
    subprocess.check_output(["git", "rev-parse", "--show-toplevel"])
except Exception:
    exit(1)

# walk through the local branches
# if local branch is not in remote branch list
# prepare for removing
remote_branches = find_remote_branches()
local_branches = find_local_branches()
live_branches = find_live_branches()
remote_branches = analyze_live_and_remote(live_branches, remote_branches)

to_remove = find_to_remove(local=local_branches, remote=remote_branches)

delete_branches(to_remove)