fix(git): handle divergent branches safely + datetime fallback

- Use --ff-only flag to detect non-fast-forward situations
- Create backup branch before resetting divergent local branch
- Reset to remote branch when fast-forward is not possible
- Add timestamp_utils.py for Mac datetime module compatibility
- Migrate all datetime usages to centralized utilities
- Bump version to 4.0.3b5

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

comfyui_manager/common/__init__.py

@@ -0,0 +1,17 @@
+from .timestamp_utils import (
+    current_timestamp,
+    get_timestamp_for_filename,
+    get_timestamp_for_path,
+    get_backup_branch_name,
+    get_now,
+    get_unix_timestamp,
+)
+
+__all__ = [
+    'current_timestamp',
+    'get_timestamp_for_filename',
+    'get_timestamp_for_path',
+    'get_backup_branch_name',
+    'get_now',
+    'get_unix_timestamp',
+]

comfyui_manager/common/git_helper.py

@@ -9,6 +9,7 @@ import yaml
 import requests
 from tqdm.auto import tqdm
 from git.remote import RemoteProgress
+from comfyui_manager.common.timestamp_utils import get_backup_branch_name
 
 
 comfy_path = os.environ.get('COMFYUI_PATH')
@@ -222,7 +223,14 @@ def gitpull(path):
             repo.close()
             return
 
-        remote.pull()
+        try:
+            repo.git.pull('--ff-only')
+        except git.GitCommandError:
+            backup_name = get_backup_branch_name(repo)
+            repo.create_head(backup_name)
+            print(f"[ComfyUI-Manager] Cannot fast-forward. Backup created: {backup_name}")
+            repo.git.reset('--hard', f'{remote_name}/{branch_name}')
+            print(f"[ComfyUI-Manager] Reset to {remote_name}/{branch_name}")
 
         repo.git.submodule('update', '--init', '--recursive')
         new_commit_hash = repo.head.commit.hexsha

comfyui_manager/common/manager_util.py

@@ -8,13 +8,13 @@ import aiohttp
 import json
 import threading
 import os
-from datetime import datetime
 import subprocess
 import sys
 import re
 import logging
 import platform
 import shlex
+import time
 from functools import lru_cache
 
 
@@ -176,7 +176,7 @@ def is_file_created_within_one_day(file_path):
         return False
 
     file_creation_time = os.path.getctime(file_path)
-    current_time = datetime.now().timestamp()
+    current_time = time.time()
     time_difference = current_time - file_creation_time
 
     return time_difference <= 86400

comfyui_manager/common/timestamp_utils.py

@@ -0,0 +1,136 @@
+"""
+Robust timestamp utilities with datetime fallback.
+
+Some environments (especially Mac) have issues with the datetime module
+due to local file name conflicts or Homebrew Python module path issues.
+"""
+
+import logging
+import time as time_module
+import uuid
+
+_datetime_available = None
+_dt_datetime = None
+
+
+def _init_datetime():
+    """Initialize datetime availability check (lazy, once)."""
+    global _datetime_available, _dt_datetime
+    if _datetime_available is not None:
+        return
+
+    try:
+        import datetime as dt
+        if hasattr(dt, 'datetime'):
+            from datetime import datetime as dt_datetime
+            _dt_datetime = dt_datetime
+            _datetime_available = True
+            return
+    except Exception as e:
+        logging.debug(f"[ComfyUI-Manager] datetime import failed: {e}")
+
+    _datetime_available = False
+    logging.warning("[ComfyUI-Manager] datetime unavailable, using time module fallback")
+
+
+def current_timestamp() -> str:
+    """
+    Get current timestamp for logging.
+    Format: YYYY-MM-DD HH:MM:SS.mmm (or Unix timestamp if fallback)
+    """
+    _init_datetime()
+    if _datetime_available:
+        return _dt_datetime.now().strftime('%Y-%m-%d %H:%M:%S.%f')[:-3]
+    return str(time_module.time()).split('.')[0]
+
+
+def get_timestamp_for_filename() -> str:
+    """
+    Get timestamp suitable for filenames.
+    Format: YYYYMMDD_HHMMSS
+    """
+    _init_datetime()
+    if _datetime_available:
+        return _dt_datetime.now().strftime('%Y%m%d_%H%M%S')
+    return time_module.strftime('%Y%m%d_%H%M%S')
+
+
+def get_timestamp_for_path() -> str:
+    """
+    Get timestamp for path/directory names.
+    Format: YYYY-MM-DD_HH-MM-SS
+    """
+    _init_datetime()
+    if _datetime_available:
+        return _dt_datetime.now().strftime('%Y-%m-%d_%H-%M-%S')
+    return time_module.strftime('%Y-%m-%d_%H-%M-%S')
+
+
+def get_backup_branch_name(repo=None) -> str:
+    """
+    Get backup branch name with current timestamp.
+    Format: backup_YYYYMMDD_HHMMSS (or backup_YYYYMMDD_HHMMSS_N if exists)
+
+    Args:
+        repo: Optional git.Repo object. If provided, checks for name collisions
+              and adds sequential suffix if needed.
+
+    Returns:
+        Unique backup branch name.
+    """
+    base_name = f'backup_{get_timestamp_for_filename()}'
+
+    if repo is None:
+        return base_name
+
+    # Check if branch exists
+    try:
+        existing_branches = {b.name for b in repo.heads}
+    except Exception:
+        return base_name
+
+    if base_name not in existing_branches:
+        return base_name
+
+    # Add sequential suffix
+    for i in range(1, 100):
+        new_name = f'{base_name}_{i}'
+        if new_name not in existing_branches:
+            return new_name
+
+    # Ultimate fallback: use UUID (very unlikely to reach here)
+    return f'{base_name}_{uuid.uuid4().hex[:6]}'
+
+
+def get_now():
+    """
+    Get current datetime object.
+    Returns datetime.now() if available, otherwise a FakeDatetime object
+    that supports basic operations (timestamp(), strftime()).
+    """
+    _init_datetime()
+    if _datetime_available:
+        return _dt_datetime.now()
+
+    # Fallback: return object with basic datetime-like interface
+    t = time_module.localtime()
+
+    class FakeDatetime:
+        def timestamp(self):
+            return time_module.time()
+
+        def strftime(self, fmt):
+            return time_module.strftime(fmt, t)
+
+        def isoformat(self):
+            return time_module.strftime('%Y-%m-%dT%H:%M:%S', t)
+
+    return FakeDatetime()
+
+
+def get_unix_timestamp() -> float:
+    """Get current Unix timestamp."""
+    _init_datetime()
+    if _datetime_available:
+        return _dt_datetime.now().timestamp()
+    return time_module.time()