homepage

If a PathLike args value is supported in Windows, then it must be processed through list2cmdline, in case it needs to be quoted. Also, the preferred usage is to pass args as a list when shell is false. This common case shouldn't be penalized as a TypeError. Also, passing `executable` as PathLike should be supported, as is already the case in the POSIX implementation. For example.
_execute_child:
 if executable is not None and not isinstance(executable, str):
 executable = os.fsdecode(executable)
 if not isinstance(args, str):
 try:
 args = list2cmdline(args)
 except TypeError:
 if isinstance(args, bytes):
 args = os.fsdecode(args)
 elif isinstance(args, os.PathLike):
 args = list2cmdline([args])
 else:
 raise
 
list2cmdline should support PathLike arguments via os.fsdecode. This removes an existing inconsistency since the POSIX implementation converts args via PyUnicode_FSConverter in Modules/_posixsubprocess.c. For example:
list2cmdline:
 for arg in seq:
 if not isinstance(arg, str):
 arg = os.fsdecode(arg)
Finally, passing args as a string when shell is false can never be deprecated on Windows. list2cmdline works in most cases, but Windows CreateProcess takes a command line, and applications are free to parse the command line however they want. IMHO, the case that should be deprecated is passing args as a list/sequence when shell is true.