content: -- |
  
  module Diagrams.Test.Angle where
  
  
  import           Test.Tasty
  import           Test.Tasty.QuickCheck
  import           Diagrams.Prelude
  import Instances
  
  tests :: TestTree
  tests = testGroup "Angle" [
           testProperty "2π radians per turn" $
             \θ -> θ^.rad =~ θ^.turn*2*(pi :: Double)
           , testProperty "360 degrees per turn" $
             \θ -> θ^.deg =~ θ^.turn*(360 :: Double)
           , testProperty "Angle vector addition is commutative" $
             \θ φ -> (θ :: Angle Double) ^+^ φ =~ φ ^+^ θ
           , testProperty "Angle subtraction is the inverse of addition" $
             \θ φ -> (θ :: Angle Double) ^+^ φ ^-^ φ =~ θ
           , testProperty "Angle vector negation squared is identity" $
             \θ -> negated (negated (θ :: Angle Double)) =~ θ
           , testProperty "A negated angle is the additive inverse of the original" $
             \θ -> (θ :: Angle Double) ^+^ (negated θ) =~ 0@@turn
           , testProperty "A negated angle is the additive inverse of the original" $
             \θ -> (θ :: Angle Double) ^+^ (negated θ) =~ 0@@turn
  
  
        ]
  