X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FTests%2FCardinal.hs;h=c3f60e58c274c41555c1f8d4217c9ab890469223;hb=6753d25156abb39ec68b715782b49f525e70b991;hp=907e3d9968ad8fbb838c922f24a6bccd201fe76f;hpb=1cd046dec9888b04b8687759282880194117736e;p=spline3.git

diff --git a/src/Tests/Cardinal.hs b/src/Tests/Cardinal.hs
index 907e3d9..c3f60e5 100644
--- a/src/Tests/Cardinal.hs
+++ b/src/Tests/Cardinal.hs
@@ -3,6 +3,7 @@ where
 
 import Control.Monad (liftM, liftM2)
 import Prelude hiding (LT)
+import Test.HUnit
 import Test.QuickCheck
 
 import Cardinal
@@ -48,13 +49,53 @@ instance Arbitrary Cardinal where
           cquot = liftM2 Quotient arbitrary arbitrary
 
 
+-- | We know what (c t6 2 1 0 0) should be from Sorokina and
+--   Zeilfelder, p. 87.  This test checks that the directions are
+--   rotated properly.  The order of the letters has to be just right
+--   since I haven't defined a proper Eq instance for Cardinals.
+test_c_tilde_2100_rotation_correct :: Test
+test_c_tilde_2100_rotation_correct =
+    TestCase $ assertEqual "auto-rotate equals manual rotate" ((ccwz . ccwz . cwy) expr1) expr2
+    where
+      expr1 =
+          (3/8)*I +
+          (1/12)*(T + R + L + D) +
+          (1/64)*(FT + FR + FL + FD) +
+          (7/48)*F +
+          (1/48)*B +
+          (1/96)*(RT + LD + LT + RD) +
+          (1/192)*(BT + BR + BL + BD)
+
+      expr2 =
+          (3/8)*I +
+          (1/12)*(F + L + R + B) +
+          (1/64)*(FT + LT + RT + BT) +
+          (7/48)*T +
+          (1/48)*D +
+          (1/96)*(FL + BR + FR + BL) +
+          (1/192)*(FD + LD + RD + BD)
+
+cardinal_tests :: [Test]
+cardinal_tests = [test_c_tilde_2100_rotation_correct]
+
+-- | A list of all directions, sans the interior and composite types.
+all_directions :: [Cardinal]
+all_directions = [L, R, F, B, D, T, FL, FR, FD, FT,
+                  BL, BR, BD, BT, LD, LT, RD, RT, FLD,
+                  FLT, FRD, FRT, BLD, BLT, BRD, BRT]
+
+
+-- | If we rotate a direction (other than front or back)
+--   counter-clockwise with respect to the x-axis, we should get a new
+--   direction.
 prop_ccwx_rotation_changes_direction :: Cardinal -> Property
 prop_ccwx_rotation_changes_direction c =
-    -- The front and back faces are unchanged by x-rotation.
     c `elem` [L, R, D, T, FL, FR, FD, FT, BL, BR, BD, BT, LD, LT,
                RD, RT, FLD, FLT, FRD, FRT, BLD, BLT, BRD, BRT]
           ==> ccwx c /= c
 
+-- | If we rotate a direction (other than front or back) clockwise
+--   with respect to the x-axis, we should get a new direction.
 prop_cwx_rotation_changes_direction :: Cardinal -> Property
 prop_cwx_rotation_changes_direction c =
     -- The front and back faces are unchanged by x-rotation.
@@ -62,6 +103,97 @@ prop_cwx_rotation_changes_direction c =
                RD, RT, FLD, FLT, FRD, FRT, BLD, BLT, BRD, BRT]
           ==> cwx c /= c
 
+-- | If we rotate a direction (other than left or right)
+--   counter-clockwise with respect to the y-axis, we should get a new
+--   direction.
+prop_ccwy_rotation_changes_direction :: Cardinal -> Property
+prop_ccwy_rotation_changes_direction c =
+    c `elem` [F, B, D, T, FL, FR, FD, FT, BL, BR, BD, BT, LD, LT,
+               RD, RT, FLD, FLT, FRD, FRT, BLD, BLT, BRD, BRT]
+          ==> ccwy c /= c
+
+
+-- | If we rotate a direction (other than left or right) clockwise
+--   with respect to the y-axis, we should get a new direction.
+prop_cwy_rotation_changes_direction :: Cardinal -> Property
+prop_cwy_rotation_changes_direction c =
+    c `elem` [F, B, D, T, FL, FR, FD, FT, BL, BR, BD, BT, LD, LT,
+               RD, RT, FLD, FLT, FRD, FRT, BLD, BLT, BRD, BRT]
+          ==> cwy c /= c
+
+
+-- | If we rotate a direction (other than top or down)
+--   counter-clockwise with respect to the z-axis, we should get a new
+--   direction.
+prop_ccwz_rotation_changes_direction :: Cardinal -> Property
+prop_ccwz_rotation_changes_direction c =
+    c `elem` [L, R, F, B, FL, FR, FD, FT, BL, BR, BD, BT, LD, LT,
+               RD, RT, FLD, FLT, FRD, FRT, BLD, BLT, BRD, BRT]
+          ==> ccwz c /= c
+
+
+-- | If we rotate a direction (other than top or down) clockwise with
+--   respect to the z-axis, we should get a new direction.
+prop_cwz_rotation_changes_direction :: Cardinal -> Property
+prop_cwz_rotation_changes_direction c =
+    c `elem` [L, R, F, B, FL, FR, FD, FT, BL, BR, BD, BT, LD, LT,
+               RD, RT, FLD, FLT, FRD, FRT, BLD, BLT, BRD, BRT]
+          ==> cwz c /= c
+
+
+-- | If we are given a direction c, there should only be one direction
+--   d which, when rotated counter-clockwise with respect to the
+--   x-axis, produces c.
+prop_ccwx_rotation_result_unique :: Cardinal -> Property
+prop_ccwx_rotation_result_unique c =
+    c `elem` all_directions ==>
+          (length [ d | d <- all_directions, ccwx d == c ]) == 1
+
+-- | If we are given a direction c, there should only be one direction
+--   d which, when rotated clockwise with respect to the x-axis,
+--   produces c.
+prop_cwx_rotation_result_unique :: Cardinal -> Property
+prop_cwx_rotation_result_unique c =
+    c `elem` all_directions ==>
+          (length [ d | d <- all_directions, cwx d == c ]) == 1
+
+
+-- | If we are given a direction c, there should only be one direction
+--   d which, when rotated counter-clockwise with respect to the
+--   y-axis, produces c.
+prop_ccwy_rotation_result_unique :: Cardinal -> Property
+prop_ccwy_rotation_result_unique c =
+    c `elem` all_directions ==>
+          (length [ d | d <- all_directions, ccwy d == c ]) == 1
+
+
+-- | If we are given a direction c, there should only be one direction
+--   d which, when rotated clockwise with respect to the y-axis,
+--   produces c.
+prop_cwy_rotation_result_unique :: Cardinal -> Property
+prop_cwy_rotation_result_unique c =
+    c `elem` all_directions ==>
+          (length [ d | d <- all_directions, cwy d == c ]) == 1
+
+
+-- | If we are given a direction c, there should only be one direction
+--   d which, when rotated counter-clockwise with respect to the
+--   z-axis, produces c.
+prop_ccwz_rotation_result_unique :: Cardinal -> Property
+prop_ccwz_rotation_result_unique c =
+    c `elem` all_directions ==>
+          (length [ d | d <- all_directions, ccwz d == c ]) == 1
+
+
+-- | If we are given a direction c, there should only be one direction
+--   d which, when rotated clockwise with respect to the z-axis,
+--   produces c.
+prop_cwz_rotation_result_unique :: Cardinal -> Property
+prop_cwz_rotation_result_unique c =
+    c `elem` all_directions ==>
+          (length [ d | d <- all_directions, cwz d == c ]) == 1
+
+
 -- | If you rotate a cardinal direction four times in the clockwise
 --   (with respect to x) direction, you should wind up with the same
 --   direction.