Two compatibility bugs: serve_file path corruption + effective_ids crash

[twilso24]

Summary

Two Windows compatibility bugs introduced in open-terminal that prevent the server from functioning on Windows.

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Bug 1: /files/serve/ returns 404 for valid files (path corruption)

Location: main.py, serve_file() function (line ~651-653)

Problem: The /files/serve/{path:path} route always prepends a / to the path before passing to view_file():
python
async def serve_file(path: str, fs: UserFS = Depends(get_file_system)):
return await view_file(path=f"/{path}", fs=fs)```

On Windows, file paths use drive letters like C:/Users/.... After prepending /, the path becomes /C:/Users/..., which is not a valid Windows path. This causes os.path.isfile() to return False, resulting in:

{"detail": "File not found"}

Request that triggers it:

GET /files/serve/C%3A/Users/USER/Desktop/Proj/index.html HTTP/1.1

Fix: Detect Windows drive letters and skip the / prepend:

if not (path.startswith("/") or (len(path) >= 2 and path[1] == ":")):
path = f"/{path}"
return await view_file(path=path, fs=fs)

###Bug 2: _is_writable_sync() crashes with NotImplementedError

Location: utils/fs.py, _is_writable_sync() method (line ~194)

Problem: Uses os.access(path, os.W_OK, effective_ids=True) which is only available on Unix:

return os.access(path, os.W_OK, effective_ids=True)

On Windows, this raises:

NotImplementedError: access: effective_ids unavailable on this platform
This crashes any endpoint that calls listdir(), glob_search(), or other directory listing operations, returning HTTP 500.

Fix: Catch NotImplementedError in addition to TypeError:

except (TypeError, NotImplementedError):
return os.access(path, os.W_OK)

Environment
OS: Windows 11
Python: 3.13 (base conda) and 3.11 (open-terminal env)

Workaround
Manual patches applied to both main.py and utils/fs.py resolve both issues. A proper fix in upstream would be appreciated.