Hg add branch name to commits

.hgco.py

def prefix_commit_message(repo, **kwargs):
    commitctx = repo.commitctx

    def rewrite_ctx(ctx, error):
        branch_name = ctx.branch()
        old_text = ctx._text
        if branch_name not in old_text:
            ctx._text = "{}: {}".format(branch_name, old_text)

        return commitctx(ctx, error)

    repo.commitctx = rewrite_ctx

.hgrc

[hooks]
precommit = python:~/.hgco.py:prefix_commit_message

[alias]
co = commit -m