Serialise instance of Data is broken

plutus-tx/plutus-tx.cabal

@@ -88,3 +88,19 @@ library
         lens -any,
         ghc-prim -any,
         aeson -any
+
+test-suite plutus-tx-test
+    import: lang
+    type: exitcode-stdio-1.0
+    main-is: Spec.hs
+    hs-source-dirs: test
+    build-depends:
+        base >=4.9 && <5,
+        plutus-tx -any,
+        bytestring -any,
+        hedgehog -any,
+        tasty -any,
+        tasty-hunit -any,
+        tasty-hedgehog -any,
+        serialise -any,
+

plutus-tx/test/Spec.hs

@@ -0,0 +1,43 @@
+module Main(main) where
+
+import           Codec.Serialise        (deserialiseOrFail, serialise)
+import           Hedgehog               (MonadGen, Property, annotateShow, assert, forAll, property)
+import qualified Hedgehog.Gen           as Gen
+import qualified Hedgehog.Range         as Range
+import           Language.PlutusTx.Data (Data (..))
+import           Test.Tasty
+import           Test.Tasty.Hedgehog    (testProperty)
+
+main :: IO ()
+main = defaultMain tests
+
+tests :: TestTree
+tests = testGroup "plutus-tx" [
+    serdeTests
+    ]
+
+serdeTests :: TestTree
+serdeTests = testGroup "Data serialisation" [
+    testProperty "should round-trip" dataRoundTrip
+    ]
+
+dataRoundTrip :: Property
+dataRoundTrip = property $ do
+    dt <- forAll genData
+    let res = deserialiseOrFail (serialise dt)
+    annotateShow res
+    assert (res == Right dt)
+
+genData :: MonadGen m => m Data
+genData =
+    let positiveInteger = Gen.integral (Range.linear 0 100000)
+        constructorArgList = Gen.list (Range.linear 0 50) genData
+        kvMapList = Gen.list (Range.linear 0 100) ((,) <$> genData <*> genData)
+    in
+    Gen.recursive Gen.choice
+        [ I <$> Gen.integral (Range.linear (-100000) 100000)
+        , B <$> Gen.bytes (Range.linear 0 1000) ]
+        [ Constr <$> positiveInteger <*> constructorArgList
+        , List <$> constructorArgList
+        , Map <$> kvMapList
+        ]