This seems to work already. Detects the example in the issue.
I also ran this on master-compatible UFOs built from Noto Sans,
and detected several issues. Confirmed visuall in AxisPraxis that
theta.sc for example has wrong starting point in that font:
Glyph theta.sc was not compatible:
Contour start point differs: NotoSans-DisplayRegular, NotoSans-DisplaySemiBoldCondensed
Contour start point differs: NotoSans-DisplayRegular, NotoSans-DisplaySemiBoldCondensed
Contour start point differs: NotoSans-DisplaySemiBoldCondensed, NotoSans-DisplaySemiBold
Contour start point differs: NotoSans-DisplaySemiBoldCondensed, NotoSans-DisplaySemiBold
There's a TODO item left to be done, which is to check for mirrored
contours and rotations thereof.
Towards fixing https://github.com/fonttools/fonttools/issues/1801