Add some tests for rational-valued functor

tests/Copar/Functors/GroupValuedSpec.hs

@@ -5,6 +5,7 @@ import           Test.Hspec.Megaparsec
 import           TestHelpers
 
 import           Data.Complex
+import           Data.Ratio
 
 import           Copar.Functors.GroupValued
 import           Copar.Coalgebra.Parser
@@ -18,6 +19,7 @@ spec = do
   parseMorphismPointIntSpec
   parseMorphismPointDoubleSpec
   parseMorphismPointComplexSpec
+  parseMorphismPointRationalSpec
 
 
 parseMorphismPointIntSpec :: Spec
@@ -97,3 +99,20 @@ parseMorphismPointComplexSpec = describe "parseMorphismPoint (Complex)" $ do
     [(0, Sorted 1 (c (-2.3) 0), 0)]
 
   where c a b = OrderedComplex (a :+ b)
+
+parseMorphismPointRationalSpec :: Spec
+parseMorphismPointRationalSpec = describe "parseMorphismPoint (Rational)" $ do
+  let p = fmap snd . parseMorphisms
+        (Functor 1 (GroupValued @(Ratio Int) Variable))
+        EnableSanityChecks
+        ""
+
+  it "parses a simple example"
+    $ p "x: {x: 1/5, y: 3/7}\ny: {}"
+    `shouldParse` encoding [(Sorted 1 (22%35)), (Sorted 1 0)]
+                           [(0, (Sorted 1 (1%5)), 0), (0, (Sorted 1 (3%7)), 1)]
+
+  it "parses negative values"
+    $ p "x: {x: -1/5, y: -3/7}\ny: {}"
+    `shouldParse` encoding [(Sorted 1 (-22%35)), (Sorted 1 0)]
+                           [(0, (Sorted 1 (-1%5)), 0), (0, (Sorted 1 (-3%7)), 1)]