small python script to walk the git reflog to find a working version after rebase failure

walk_reflog.py

#!/usr/bin/env python3

import subprocess
import sys
from pathlib import Path


def get_reflog_entries():
    """Get list of reflog entries (commit hashes) for current branch"""
    # Get current branch name
    branch_result = subprocess.run(
        ["git", "branch", "--show-current"],
        capture_output=True,
        text=True,
        check=True
    )
    current_branch = branch_result.stdout.strip()
    
    # Get reflog entries for current branch only
    result = subprocess.run(
        ["git", "reflog", current_branch, "--format=%H"],
        capture_output=True,
        text=True,
        check=True
    )
    return result.stdout.strip().split('\n')


def test_commit(commit_hash, base_path):
    """Test a commit by creating worktree and running checks"""
    worktree_path = base_path / f"test-{commit_hash[:8]}"
    
    try:
        # Create worktree
        subprocess.run(
            ["git", "worktree", "add", str(worktree_path), commit_hash],
            check=True,
            capture_output=True
        )
        
        # Run ruff check
        ruff_result = subprocess.run(
            ["uv", "run", "ruff", "check", "--output-format=concise"],
            cwd=worktree_path,
            capture_output=True,
            text=True
        )
        
        if ruff_result.returncode != 0:
            print(f"{commit_hash[:8]}: ruff failed")
            if ruff_result.stdout:
                print(ruff_result.stdout)
            return False
            
        # Run pytest
        pytest_result = subprocess.run(
            ["uv", "run", "pytest", "-q"],
            cwd=worktree_path,
            capture_output=True,
            text=True
        )
        
        if pytest_result.returncode != 0:
            print(f"{commit_hash[:8]}: pytest failed")
            if pytest_result.stdout:
                print(pytest_result.stdout)
            return False
            
        print(f"{commit_hash[:8]}: SUCCESS")
        return True
        
    finally:
        # Cleanup worktree
        if worktree_path.exists():
            subprocess.run(
                ["git", "worktree", "remove", str(worktree_path)],
                capture_output=True
            )


def main():
    base_path = Path.cwd()
    reflog_entries = get_reflog_entries()
    
    for commit_hash in reflog_entries:
        if test_commit(commit_hash, base_path):
            print(f"First working commit: {commit_hash}")
            sys.exit(0)
    
    print("No working commit found")
    sys.exit(1)


if __name__ == "__main__":
    main()