Under-the-hood functionality in pathlib is divided between:

- The 'flavour', which implements path syntax (separators, casefolding, etc)
- The 'accessor', which accesses the local (file)system.

The '_WindowsFlavour/_PosixFlavour.resolve()' function is misplaced, as it requires OS calls such as `os.getcwd()`, `os.readlink()`, and `nt._getfinalpathname()`. While the implementation *does* differ across Windows and POSIX, it's still properly part of the accessor interface, and not the flavour interface.

In preparation for addressing bpo-24132 I'd like to get these interfaces really tidy. Once bpo-39899 is fixed, this will be the last remaining flavour method that does accessor-y things.