extenvvars stopped working, retrieving "library" directories

[quintijn]

For extracting paths of library directories (like "Documents", "Music" etc), a function SHGetFolderPath was used from "from win32com.shell import shell". This one stopped working, despite the post install of win32.

Maybe this can be repaired. If not, we don't go further than platformdirs goes. Oops, the functions are here too!! platformdirs, windows.py, near line 200...

def get_win_folder_via_ctypes(csidl_name: str) -> str:
    """Get folder with ctypes."""
    # There is no 'CSIDL_DOWNLOADS'.
    # Use 'CSIDL_PROFILE' (40) and append the default folder 'Downloads' instead.
    # https://learn.microsoft.com/en-us/windows/win32/shell/knownfolderid

    csidl_const = {
        "CSIDL_APPDATA": 26,
        "CSIDL_COMMON_APPDATA": 35,
        "CSIDL_LOCAL_APPDATA": 28,
        "CSIDL_PERSONAL": 5,
        "CSIDL_MYPICTURES": 39,
        "CSIDL_MYVIDEO": 14,
        "CSIDL_MYMUSIC": 13,
        "CSIDL_DOWNLOADS": 40,
        "CSIDL_DESKTOPDIRECTORY": 16,
    }.get(csidl_name)
    if csidl_const is None:
        msg = f"Unknown CSIDL name: {csidl_name}"
        raise ValueError(msg)

    buf = ctypes.create_unicode_buffer(1024)
    windll = getattr(ctypes, "windll")  # noqa: B009 # using getattr to avoid false positive with mypy type checker
    windll.shell32.SHGetFolderPathW(None, csidl_const, None, 0, buf)

    # Downgrade to short path name if it has high-bit chars.
    if any(ord(c) > 255 for c in buf):  # noqa: PLR2004
        buf2 = ctypes.create_unicode_buffer(1024)
        if windll.kernel32.GetShortPathNameW(buf.value, buf2, 1024):
            buf = buf2

    if csidl_name == "CSIDL_DOWNLOADS":
        return os.path.join(buf.value, "Downloads")  # noqa: PTH118

    return buf.value

I think, only stick to this. I will try first (Quintijn)

[quintijn]

extenvvars.py is now reworked, and pretty much tested with test_extenvvars.py