Improve generation of inputs in NodeSpec

Author: ch1bo

hydra-node/test/Hydra/NodeSpec.hs

@@ -42,7 +42,7 @@ import Hydra.Options (defaultContestationPeriod)
 import Hydra.Party (Party, deriveParty)
 import Hydra.Persistence (PersistenceIncremental (..), eventPairFromPersistenceIncremental)
 import Test.Hydra.Fixture (alice, aliceSk, bob, bobSk, carol, carolSk, cperiod, deriveOnChainId, testEnvironment, testHeadId, testHeadSeed)
-import Test.QuickCheck (classify, counterexample, elements, forAllBlind, forAllShrink, forAllShrinkBlind, idempotentIOProperty, listOf, listOf1, (==>))
+import Test.QuickCheck (classify, counterexample, elements, forAllBlind, forAllShrink, forAllShrinkBlind, idempotentIOProperty, listOf, listOf1, resize, (==>))
 import Test.Util (isStrictlyMonotonic)
 
 spec :: Spec
@@ -112,16 +112,19 @@ spec = parallel $ do
         getMockSinkEvents2 `shouldReturn` events
 
       it "event ids are strictly monotonic" $ \dryNode -> do
-        forAllShrinkBlind arbitrary shrink $ \someInputs ->
+        -- NOTE: Arbitrary inputs in open head state results more likely in
+        -- multiple state change events per input (during tx processing).
+        let genInputs = do
+              -- Resize to reducing complexity of additional input contents
+              someInput <- resize 1 arbitrary
+              pure $ inputsToOpenHead <> [someInput]
+
+        forAllShrinkBlind genInputs shrink $ \someInputs ->
           idempotentIOProperty $ do
             (sink, getSinkEvents) <- createRecordingSink
-
             hydrate (mockSource []) [sink] dryNode
               >>= notConnect
-              -- NOTE: Arbitrary inputs in open head state results more likely
-              -- in multiple state change events per input (during tx
-              -- processing).
-              >>= primeWith (inputsToOpenHead <> someInputs)
+              >>= primeWith someInputs
               >>= runToCompletion
 
             events <- getSinkEvents
@@ -131,7 +134,7 @@ spec = parallel $ do
                 & counterexample "Not strictly monotonic"
                 & counterexample ("Event ids: " <> show eventIds)
                 & counterexample ("Events: " <> show events)
-                & counterexample ("Additional inputs: " <> show someInputs)
+                & counterexample ("Inputs: " <> show someInputs)
                 & classify (null eventIds) "empty list of events"
 
       it "can continue after re-hydration" $ \dryNode ->