module Tests.Face
where

import Test.QuickCheck

import Cube (Cube(grid))
import Face (tetrahedrons)
import Grid (Grid(h))
import Tetrahedron (volume)

-- QuickCheck Tests.
prop_all_volumes_nonnegative :: Cube -> Property
prop_all_volumes_nonnegative c =
    (delta > 0) ==> (null negative_volumes)
    where
      delta = h (grid c)
      ts = tetrahedrons c
      volumes = map volume ts
      negative_volumes = filter (< 0) volumes