def METHOD_NAME(self):
    for ichild, edges in enumerate(self.ref.connectivity):
        for iedge, ioppchild in enumerate(edges):
            if ioppchild != -1:
                self.assertIn(ichild, self.ref.connectivity[ioppchild])
                ioppedge = util.index(self.ref.connectivity[ioppchild], ichild)
                self.assertEqual(
                    self.ref.child_transforms[ichild] * self.ref.child_refs[ichild].edge_transforms[iedge],
                    (self.ref.child_transforms[ioppchild] * self.ref.child_refs[ioppchild].edge_transforms[ioppedge]).flipped)