Simple git worktree filters in Python. Sample usage: `cd $(worktrees.py ~/myrepo max_path)`

worktrees.py

#!/usr/bin/env python3

import argparse
import os
import subprocess
import sys
from dataclasses import dataclass


@dataclass
class WorktreeInfo:
    bools: set
    attrs: dict

    def is_(self, label):
        return label in self.bools

    def get(self, label):
        return self.attrs.get(label)

    @property
    def path(self):
        return self.get("worktree")

    @property
    def is_bare(self):
        return self.is_("bare")

    @property
    def head(self):
        return self.get("HEAD")

    @staticmethod
    def create(lines):
        assert lines
        bools = set()
        attrs = dict()
        for line in lines:
            line = line.decode("utf-8")
            if " " in line:
                label, value = line.split(maxsplit=1)
                attrs[label] = value
            else:
                bools.add(line)
        return WorktreeInfo(bools=bools, attrs=attrs)


def get_worktrees(git_dir):
    result = subprocess.run(
        ["git", "worktree", "list", "--porcelain", "-z"],
        cwd=git_dir,
        capture_output=True,
    )
    return (
        WorktreeInfo.create(blob.split(bytes(1)))
        for blob in result.stdout.rstrip(bytes(1)).split(bytes(2))
    )


def max_worktree(git_dir):
    "sort by last path element"
    return max(
        (x for x in get_worktrees(git_dir) if not x.is_bare),
        key=lambda x: float(x.path.split("/")[-1]),
    )


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("git_dir")
    parser.add_argument("filter", choices=["max_path"])
    args = parser.parse_args()

    if args.filter == "max_path":
        path = max_worktree(args.git_dir).path
        # support relative worktree paths
        print(os.path.join(args.git_dir, path) if path.startswith(".") else path)


if __name__ == "__main__":
    main()