1 files changed, 17 insertions, 0 deletions

diff --git a/spec/test/Thermoprint/PrintoutSpec.hs b/spec/test/Thermoprint/PrintoutSpec.hs
index 5a48496..b92d76a 100644
--- a/spec/test/Thermoprint/PrintoutSpec.hs
+++ b/spec/test/Thermoprint/PrintoutSpec.hs
@@ -1,9 +1,26 @@
+{-# LANGUAGE StandaloneDeriving #-}
+
 module Thermoprint.PrintoutSpec (spec) where
 
 import Test.Hspec
 import Test.Hspec.QuickCheck (prop)
 import Thermoprint.Printout
 
+import Data.Aeson (fromJSON, ToJSON(..), Result(..))
+import Data.Function (on)
+
+import Control.DeepSeq (($!!), force)
+
+-- Equality via cotext on Block
+instance Eq Block where
+  (==) = (==) `on` cotext
+-- Structural equality for Chunk 
+deriving instance Eq Chunk
+
 spec :: Spec
 spec = do
   prop "prop_text" prop_text
+  prop "json" prop_json
+  where
+    prop_json :: Printout -> Bool
+    prop_json p = force $ (== Success p) . fromJSON . toJSON $!! p