[Path.GetFullPath](https://docs.microsoft.com/en-us/dotnet/api/system.io.path.getfullpath) has two overloads, one taking a single string and one [taking two strings](https://docs.microsoft.com/en-us/dotnet/api/system.io.path.getfullpath?view=netcore-3.1#System_IO_Path_GetFullPath_System_String_System_String_). IPath is missing the two string parameter version
Path.GetFullPath has two overloads, one taking a single string and one taking two strings. IPath is missing the two string parameter version