implemented movement of single beads

test/Abacus/App/ActionsSpec.hs

@@ -24,6 +24,8 @@ module Abacus.App.ActionsSpec (spec) where
 import Lens.Micro.Platform ((&), (.~))
 import Test.Hspec (Spec, context, describe, it, shouldBe)
 
+import Abacus
+import Abacus.Internal
 import Abacus.App.Actions
 import Abacus.App.Types
 
@@ -31,6 +33,8 @@ spec :: Spec
 spec = describe "Actions" $ do
   moveUpSpec
   moveDownSpec
+  beadLeftSpec
+  beadRightSpec
 
 moveUpSpec :: Spec
 moveUpSpec = describe "moveUp" $ mapM_
@@ -62,4 +66,22 @@ moveDownSpec = describe "moveDown" $ mapM_
     elsewhere = initialState & rungNum .~ 8
     movedDown = initialState & rungNum .~ 1
 
+beadLeftSpec :: Spec
+beadLeftSpec = describe "beadLeft" $ let
+  state = initialState
+    & abacus .~ Abacus 10 [1..10]
+    & rungNum .~ 5
+  expected = state & abacus.rungL 5 .~ 5
+  in it ("should be " ++ show expected) $
+    beadLeft state `shouldBe` expected
+
+beadRightSpec :: Spec
+beadRightSpec = describe "beadRight" $ let
+  state = initialState
+    & abacus .~ Abacus 10 [1..10]
+    & rungNum .~ 5
+  expected = state & abacus.rungL 5 .~ 7
+  in it ("should be " ++ show expected) $
+    beadRight state `shouldBe` expected
+
 --jl