parent_path() edge case returns wrong result on Windows

[Alex Weiss <alexweiss86@…>]

The path "C:
", while unusual, is legal in Windows and equivalent to "C:\". According to the path decomposition table, that means that

parent_path(L"C:\\\\")

should return "C:". However, it returns "C:\".

The same is true for every variation with more than one trailing separator (preferred or generic).

[Alex Weiss <alexweiss86@…>]

WikiFormatting mutilated the first path in my post. It is supposed to read

C:\\