I’m not sure how I feel about using surrogateescape.  The distutils source is very similar across 2.7, 3.1, 3.2 and default, especially after the Great Revert and freeze last year to restore buggy-but-known behavior while the distutils2 project was created and allowed to fix things and break stuff.  Haypo added a fix using surrogateescape in 3.2, so it couldn’t be backported to all stable branches.  You may say that at least it was fixed in one version, which is something good.  I don’t know if I’d prefer to apply the patch (if a test is provided) or to raise an exception instead of silently changing behavior.