Clean a local git repo that uses the rebase flow. Use with care!

git_cleanup.py

# pip install tqdm GitPython
from git import Repo
from git.exc import GitCommandError
from tqdm import tqdm

DEFAULT_BRANCH = "master"
IGNORED_BRANCHES = []  # develop, ...

repo = Repo(".")
branches = repo.branches
start_n = len(branches)
print(f"starting with {start_n} branches")

main = [b for b in branches if b.name == DEFAULT_BRANCH][0]
other_branches = [b for b in branches if b.name != DEFAULT_BRANCH and b.name not in IGNORED_BRANCHES]
rebase_errors = []
delete_errors = []

for branch in tqdm(other_branches):
    branch.checkout()
    n = branch.name
    try:
        repo.git.rebase(DEFAULT_BRANCH)
    except GitCommandError:
        rebase_errors.append(n)
        repo.git.rebase(abort=True)
        continue

    try:
        main.checkout()
        repo.delete_head(branch)
        print("deleted branch", n)
    except GitCommandError:
        delete_errors.append(n)
        continue

print(f"{len(rebase_errors)} rebase errors; those branches were not touched")
print(f"{len(delete_errors)} delete errors; those branches were not touched")
print(f"cleaned up {start_n - len(repo.branches)} branches")