Remove MonadRandom from consensus

Fixes #2036. Update the dependencies on `cardano-base` and `cardano-ledger-specs`, bringing in IntersectMBO/cardano-base#139 and IntersectMBO/cardano-ledger#1621, which remove `MonadRandom` from the VRF Crypto class. This means we can remove `MonadRandom` from `checkIsLeader`. The implementation code no longer mentions `MonadRandom`, but the `TxGen` used in the ThreadNet tests still does.
IntersectMBO · Jul 8, 2020 · c0d6911 · c0d6911
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diff --git a/cabal.project b/cabal.project
@@ -135,106 +135,113 @@ source-repository-package
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-base
-  tag: 5e0b8bc8c7862be12da6989440f8644ba7c1e1cf
-  --sha256: 06i2wpla5hp4vz873zqy1f2p0pmbhnkmabw3ibhcf476qh3vfa3p
+  tag: 0b84523e48f678bb267c3f1db5af91a8fc49c593
+  --sha256: 01yzpwy9msnr6dr0wyi78r4g0h777mkz0zs2wq0wnkav1lm5ph3r
   subdir: binary
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-base
-  tag: 5e0b8bc8c7862be12da6989440f8644ba7c1e1cf
-  --sha256: 06i2wpla5hp4vz873zqy1f2p0pmbhnkmabw3ibhcf476qh3vfa3p
+  tag: 0b84523e48f678bb267c3f1db5af91a8fc49c593
+  --sha256: 01yzpwy9msnr6dr0wyi78r4g0h777mkz0zs2wq0wnkav1lm5ph3r
   subdir: binary/test
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-base
-  tag: 5e0b8bc8c7862be12da6989440f8644ba7c1e1cf
-  --sha256: 06i2wpla5hp4vz873zqy1f2p0pmbhnkmabw3ibhcf476qh3vfa3p
+  tag: 0b84523e48f678bb267c3f1db5af91a8fc49c593
+  --sha256: 01yzpwy9msnr6dr0wyi78r4g0h777mkz0zs2wq0wnkav1lm5ph3r
   subdir: cardano-crypto-class
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-base
-  tag: 5e0b8bc8c7862be12da6989440f8644ba7c1e1cf
-  --sha256: 06i2wpla5hp4vz873zqy1f2p0pmbhnkmabw3ibhcf476qh3vfa3p
+  tag: 0b84523e48f678bb267c3f1db5af91a8fc49c593
+  --sha256: 01yzpwy9msnr6dr0wyi78r4g0h777mkz0zs2wq0wnkav1lm5ph3r
   subdir: cardano-crypto-praos
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-base
-  tag: 5e0b8bc8c7862be12da6989440f8644ba7c1e1cf
-  --sha256: 06i2wpla5hp4vz873zqy1f2p0pmbhnkmabw3ibhcf476qh3vfa3p
+  tag: 0b84523e48f678bb267c3f1db5af91a8fc49c593
+  --sha256: 01yzpwy9msnr6dr0wyi78r4g0h777mkz0zs2wq0wnkav1lm5ph3r
   subdir: slotting
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: semantics/executable-spec
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
+  subdir: semantics/small-steps-test
+
+source-repository-package
+  type: git
+  location: https://github.com/input-output-hk/cardano-ledger-specs
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: byron/ledger/executable-spec
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: byron/ledger/impl
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: byron/ledger/impl/test
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: byron/crypto
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: byron/crypto/test
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: byron/chain/executable-spec
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: shelley/chain-and-ledger/dependencies/non-integer
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: shelley/chain-and-ledger/executable-spec
 
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/cardano-ledger-specs
-  tag: 12b13f390d64df6af6054b0d33bb3767756da041
-  --sha256: 0v9zj73sz984xpg0azckfpibkllribbzksg18isx2m7w58bya77m
+  tag: 515b73783ada98a7ede4b6b67ef39f0959a89571
+  --sha256: 128m3ir32013id671pmymdady30sl4phfp09bjvcdb25sm2hzqdb
   subdir: shelley/chain-and-ledger/executable-spec/test
 
 source-repository-package

diff --git a/ouroboros-consensus-byron-test/ouroboros-consensus-byron-test.cabal b/ouroboros-consensus-byron-test/ouroboros-consensus-byron-test.cabal
@@ -106,6 +106,7 @@ test-suite test
                      , byron-spec-chain
                      , byron-spec-ledger
                      , small-steps
+                     , small-steps-test
 
                      , ouroboros-network
                      , ouroboros-consensus

diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion1/Block_Shelley b/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion1/Block_Shelley
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion1/Query_AnytimeShelley b/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion1/Query_AnytimeShelley
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion1/Query_Byron b/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion1/Query_Byron
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Block_Shelley b/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Block_Shelley
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_AnytimeShelley b/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_AnytimeShelley
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Byron b/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Byron
diff --git a/...consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetCurrentPParams b/...consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetCurrentPParams
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetEpochNo b/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetEpochNo
diff --git a/...oros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetLedgerTip b/...oros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetLedgerTip
diff --git a/...s-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetNonMyopicMemberRewards b/...s-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetNonMyopicMemberRewards
diff --git a/...s-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetProposedPParamsUpdates b/...s-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetProposedPParamsUpdates
diff --git a/...sensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetStakeDistribution b/...sensus-cardano/test/golden/CardanoNodeToClientVersion2/Query_Shelley_GetStakeDistribution
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Result_Shelley_LedgerTip b/ouroboros-consensus-cardano/test/golden/CardanoNodeToClientVersion2/Result_Shelley_LedgerTip
@@ -1 +1 @@
-��D��
+��D&؏o
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToNodeVersion1/Block_Shelley b/ouroboros-consensus-cardano/test/golden/CardanoNodeToNodeVersion1/Block_Shelley
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToNodeVersion2/Block_Shelley b/ouroboros-consensus-cardano/test/golden/CardanoNodeToNodeVersion2/Block_Shelley
diff --git a/ouroboros-consensus-cardano/test/golden/CardanoNodeToNodeVersion2/Header_Shelley b/ouroboros-consensus-cardano/test/golden/CardanoNodeToNodeVersion2/Header_Shelley
diff --git a/ouroboros-consensus-cardano/test/golden/disk/AnnTip_Shelley b/ouroboros-consensus-cardano/test/golden/disk/AnnTip_Shelley
@@ -1,2 +1 @@
-��D��
-�
+��D&؏o�
diff --git a/ouroboros-consensus-cardano/test/golden/disk/Block_Shelley b/ouroboros-consensus-cardano/test/golden/disk/Block_Shelley
diff --git a/ouroboros-consensus-cardano/test/golden/disk/ChainDepState_Shelley b/ouroboros-consensus-cardano/test/golden/disk/ChainDepState_Shelley
diff --git a/ouroboros-consensus-cardano/test/golden/disk/ChainDepState_WithSnapshot b/ouroboros-consensus-cardano/test/golden/disk/ChainDepState_WithSnapshot
diff --git a/ouroboros-consensus-cardano/test/golden/disk/ExtLedgerState_Shelley b/ouroboros-consensus-cardano/test/golden/disk/ExtLedgerState_Shelley
diff --git a/ouroboros-consensus-cardano/test/golden/disk/HeaderHash_Shelley b/ouroboros-consensus-cardano/test/golden/disk/HeaderHash_Shelley
@@ -1 +1 @@
-D��
+D&؏o
diff --git a/ouroboros-consensus-cardano/test/golden/disk/LedgerState_Shelley b/ouroboros-consensus-cardano/test/golden/disk/LedgerState_Shelley
diff --git a/ouroboros-consensus-cardano/test/golden/disk/LedgerState_WithSnapshot b/ouroboros-consensus-cardano/test/golden/disk/LedgerState_WithSnapshot
diff --git a/ouroboros-consensus-shelley-test/test/golden/ShelleyNodeToClientVersion1/Block b/ouroboros-consensus-shelley-test/test/golden/ShelleyNodeToClientVersion1/Block
diff --git a/ouroboros-consensus-shelley-test/test/golden/ShelleyNodeToClientVersion1/Result_LedgerTip b/ouroboros-consensus-shelley-test/test/golden/ShelleyNodeToClientVersion1/Result_LedgerTip
@@ -1 +1 @@
-�D��
+�D&؏o
diff --git a/ouroboros-consensus-shelley-test/test/golden/ShelleyNodeToNodeVersion1/Block b/ouroboros-consensus-shelley-test/test/golden/ShelleyNodeToNodeVersion1/Block
diff --git a/ouroboros-consensus-shelley-test/test/golden/ShelleyNodeToNodeVersion1/Header b/ouroboros-consensus-shelley-test/test/golden/ShelleyNodeToNodeVersion1/Header
diff --git a/ouroboros-consensus-shelley-test/test/golden/disk/AnnTip b/ouroboros-consensus-shelley-test/test/golden/disk/AnnTip
@@ -1,2 +1 @@
-�D��
-�
+�D&؏o�
diff --git a/ouroboros-consensus-shelley-test/test/golden/disk/Block b/ouroboros-consensus-shelley-test/test/golden/disk/Block
diff --git a/ouroboros-consensus-shelley-test/test/golden/disk/ChainDepState b/ouroboros-consensus-shelley-test/test/golden/disk/ChainDepState
diff --git a/ouroboros-consensus-shelley-test/test/golden/disk/ExtLedgerState b/ouroboros-consensus-shelley-test/test/golden/disk/ExtLedgerState
diff --git a/ouroboros-consensus-shelley-test/test/golden/disk/HeaderHash b/ouroboros-consensus-shelley-test/test/golden/disk/HeaderHash
@@ -1 +1 @@
-D��
+D&؏o
diff --git a/ouroboros-consensus-shelley-test/test/golden/disk/LedgerState b/ouroboros-consensus-shelley-test/test/golden/disk/LedgerState
diff --git a/ouroboros-consensus-shelley/ouroboros-consensus-shelley.cabal b/ouroboros-consensus-shelley/ouroboros-consensus-shelley.cabal
@@ -55,7 +55,6 @@ library
                      , cardano-slotting
                      , cborg             >=0.2.2 && <0.3
                      , containers        >=0.5   && <0.7
-                     , cryptonite        >=0.25  && <0.26
                      , mtl               >=2.2   && <2.3
                      , serialise         >=0.2   && <0.3
                      , transformers

diff --git a/ouroboros-consensus-shelley/src/Ouroboros/Consensus/Shelley/Protocol.hs b/ouroboros-consensus-shelley/src/Ouroboros/Consensus/Shelley/Protocol.hs
@@ -377,11 +377,9 @@ instance TPraosCrypto c => ConsensusProtocol (TPraos c) where
 
   protocolSecurityParam = tpraosSecurityParam . tpraosParams
 
-  checkIsLeader cfg@TPraosConfig{..} icn hk (Ticked slot lv) (Ticked _ cs) = do
-      rho <- VRF.evalCertified () rho' tpraosIsCoreNodeSignKeyVRF
-      y   <- VRF.evalCertified () y'   tpraosIsCoreNodeSignKeyVRF
+  checkIsLeader cfg@TPraosConfig{..} icn hk (Ticked slot lv) (Ticked _ cs) =
       -- First, check whether we're in the overlay schedule
-      return $ case Map.lookup slot (SL.lvOverlaySched lv) of
+      case Map.lookup slot (SL.lvOverlaySched lv) of
         Nothing
           | meetsLeaderThreshold cfg lv (SL.coerceKeyRole vkhCold) y
           -> case checkKesPeriod wallclockPeriod hk of
@@ -436,6 +434,9 @@ instance TPraosCrypto c => ConsensusProtocol (TPraos c) where
       rho'       = SL.mkSeed SL.seedEta slot eta0
       y'         = SL.mkSeed SL.seedL   slot eta0
 
+      rho = VRF.evalCertified () rho' tpraosIsCoreNodeSignKeyVRF
+      y   = VRF.evalCertified () y'   tpraosIsCoreNodeSignKeyVRF
+
       tickEta0 (STS.TicknState _ x) = x
 
       -- The current wallclock KES period

diff --git a/ouroboros-consensus/ouroboros-consensus-mock/src/Ouroboros/Consensus/Mock/Protocol/Praos.hs b/ouroboros-consensus/ouroboros-consensus-mock/src/Ouroboros/Consensus/Mock/Protocol/Praos.hs
@@ -256,20 +256,21 @@ instance PraosCrypto c => ConsensusProtocol (Praos c) where
   type CanBeLeader   (Praos c) = CoreNodeId
   type CannotLead    (Praos c) = Void
 
-  checkIsLeader cfg@PraosConfig{..} nid _cis (Ticked slot _u) (Ticked _ cds) = do
-      rho <- evalCertified () rho' praosSignKeyVRF
-      y   <- evalCertified () y'   praosSignKeyVRF
-      return $ if fromIntegral (getOutputVRFNatural (certifiedOutput y)) < t
-          then IsLeader PraosProof {
-                   praosProofRho  = rho
-                 , praosProofY    = y
-                 , praosLeader    = nid
-                 , praosProofSlot = slot
-                 }
-          else NotLeader
+  checkIsLeader cfg@PraosConfig{..} nid _cis (Ticked slot _u) (Ticked _ cds) =
+      if fromIntegral (getOutputVRFNatural (certifiedOutput y)) < t
+      then IsLeader PraosProof {
+               praosProofRho  = rho
+             , praosProofY    = y
+             , praosLeader    = nid
+             , praosProofSlot = slot
+             }
+      else NotLeader
     where
       (rho', y', t) = rhoYT cfg cds slot nid
 
+      rho = evalCertified () rho' praosSignKeyVRF
+      y   = evalCertified () y'   praosSignKeyVRF
+
   -- Unlike the real Praos (which must switch nonce at the right time), there
   -- is nothing to do for the mock Praos implementation in 'tickChainDepState'
   -- since we have the /full/ history, and pick the right nonce from that.

diff --git a/ouroboros-consensus/ouroboros-consensus-test-infra/ouroboros-consensus-test-infra.cabal b/ouroboros-consensus/ouroboros-consensus-test-infra/ouroboros-consensus-test-infra.cabal
@@ -26,7 +26,6 @@ library
                        Test.ThreadNet.Rekeying
                        Test.ThreadNet.TxGen
                        Test.ThreadNet.Util
-                       Test.ThreadNet.Util.BlockProduction
                        Test.ThreadNet.Util.Expectations
                        Test.ThreadNet.Util.HasCreator
                        Test.ThreadNet.Util.NodeJoinPlan

diff --git a/ouroboros-consensus/ouroboros-consensus-test-infra/src/Test/ThreadNet/Network.hs b/ouroboros-consensus/ouroboros-consensus-test-infra/src/Test/ThreadNet/Network.hs
@@ -85,6 +85,7 @@ import           Ouroboros.Consensus.Mempool
 import qualified Ouroboros.Consensus.MiniProtocol.BlockFetch.Server as BFServer
 import qualified Ouroboros.Consensus.MiniProtocol.ChainSync.Client as CSClient
 import qualified Ouroboros.Consensus.Network.NodeToNode as NTN
+import           Ouroboros.Consensus.Node.BlockProduction
 import           Ouroboros.Consensus.Node.NetworkProtocolVersion
 import           Ouroboros.Consensus.Node.ProtocolInfo
 import           Ouroboros.Consensus.Node.Run
@@ -109,7 +110,6 @@ import qualified Ouroboros.Consensus.Storage.LedgerDB.InMemory as LgrDB
 import qualified Ouroboros.Consensus.Storage.VolatileDB as VolDB
 
 import           Test.ThreadNet.TxGen
-import           Test.ThreadNet.Util.BlockProduction
 import           Test.ThreadNet.Util.NodeJoinPlan
 import           Test.ThreadNet.Util.NodeRestarts
 import           Test.ThreadNet.Util.NodeTopology
@@ -764,7 +764,7 @@ runThreadNetwork systemTime ThreadNetworkArgs
               Nothing    -> error "runThreadNetwork: cannot produce blocks"
               Just creds -> creds
 
-      blockProduction <- blockProductionIOLike pInfoConfig canBeLeader maintainForgeState varRNG $
+      blockProduction <- customForgeBlockProduction pInfoConfig canBeLeader maintainForgeState $
          \forgeState currentBno tickedLdgSt txs prf -> do
             let currentSlot  = tickedSlotNo tickedLdgSt
             let currentEpoch = HFF.futureSlotToEpoch future currentSlot

diff --git a/...boros-consensus/ouroboros-consensus-test-infra/src/Test/ThreadNet/Util/BlockProduction.hs b/...boros-consensus/ouroboros-consensus-test-infra/src/Test/ThreadNet/Util/BlockProduction.hs
diff --git a/ouroboros-consensus/ouroboros-consensus.cabal b/ouroboros-consensus/ouroboros-consensus.cabal
@@ -277,7 +277,6 @@ library
                      , cborg             >=0.2.2 && <0.3
                      , containers        >=0.5   && <0.7
                      , contra-tracer
-                     , cryptonite        >=0.25  && <0.26
                      , deepseq
                      , digest
                      , directory         >=1.3   && <1.4
@@ -397,7 +396,6 @@ test-suite test-consensus
                        Test.ThreadNet.Rekeying
                        Test.ThreadNet.TxGen
                        Test.ThreadNet.Util
-                       Test.ThreadNet.Util.BlockProduction
                        Test.ThreadNet.Util.Expectations
                        Test.ThreadNet.Util.HasCreator
                        Test.ThreadNet.Util.NodeJoinPlan

diff --git a/ouroboros-consensus/src/Ouroboros/Consensus/HardFork/Combinator/Degenerate.hs b/ouroboros-consensus/src/Ouroboros/Consensus/HardFork/Combinator/Degenerate.hs
@@ -226,7 +226,7 @@ instance SingleEraBlock b => ConsensusProtocol (DegenForkProtocol b) where
                 chainIndepState
                 tickedLedgerView
                 tickedChainDepState =
-    castLeaderCheck <$>
+    castLeaderCheck $
       checkIsLeader
         cfg
         canBeLeader