Stub out increment validator

Signed-off-by: Sasha Bogicevic <[email protected]>

hydra-plutus/src/Hydra/Contract/Head.hs

@@ -15,7 +15,7 @@ import Hydra.Cardano.Api (PlutusScriptVersion (PlutusScriptV2))
 import Hydra.Contract.Commit (Commit (..))
 import Hydra.Contract.Commit qualified as Commit
 import Hydra.Contract.HeadError (HeadError (..), errorCode)
-import Hydra.Contract.HeadState (CloseRedeemer (..), ClosedDatum (..), ContestRedeemer (..), DecrementRedeemer (..), Hash, Input (..), OpenDatum (..), Signature, SnapshotNumber, SnapshotVersion, State (..))
+import Hydra.Contract.HeadState (CloseRedeemer (..), ClosedDatum (..), ContestRedeemer (..), DecrementRedeemer (..), Hash, Input (..), OpenDatum (..), Signature, SnapshotNumber, SnapshotVersion, State (..), IncrementRedeemer)
 import Hydra.Contract.Util (hasST, mustBurnAllHeadTokens, mustNotMintOrBurn, (===))
 import Hydra.Data.ContestationPeriod (ContestationPeriod, addContestationPeriod, milliseconds)
 import Hydra.Data.Party (Party (vkey))
@@ -72,6 +72,8 @@ headValidator oldState input ctx =
       checkCollectCom ctx (contestationPeriod, parties, headId)
     (Initial{parties, headId}, Abort) ->
       checkAbort ctx headId parties
+    (Open openDatum, Increment redeemer) ->
+      checkIncrement ctx openDatum redeemer
     (Open openDatum, Decrement redeemer) ->
       checkDecrement ctx openDatum redeemer
     (Open openDatum, Close redeemer) ->
@@ -221,6 +223,16 @@ commitDatum input = do
     Nothing -> []
 {-# INLINEABLE commitDatum #-}
 
+-- | Verify a increment transaction.
+checkIncrement ::
+  ScriptContext ->
+  -- | Open state before the decrement
+  OpenDatum ->
+  IncrementRedeemer ->
+  Bool
+checkIncrement ctx openBefore redeemer = False
+{-# INLINEABLE checkIncrement #-}
+
 -- | Verify a decrement transaction.
 checkDecrement ::
   ScriptContext ->

hydra-plutus/src/Hydra/Contract/HeadState.hs

@@ -115,6 +115,12 @@ data ContestRedeemer
 
 PlutusTx.unstableMakeIsData ''ContestRedeemer
 
+-- | Sub-type for increment transition
+data IncrementRedeemer = IncrementRedeemer
+  deriving stock (Show, Generic)
+
+PlutusTx.unstableMakeIsData ''IncrementRedeemer
+
 -- | Sub-type for decrement transition with auxiliary data as needed.
 data DecrementRedeemer = DecrementRedeemer
   { signature :: [Signature]
@@ -130,6 +136,7 @@ PlutusTx.unstableMakeIsData ''DecrementRedeemer
 
 data Input
   = CollectCom
+  | Increment IncrementRedeemer
   | Decrement DecrementRedeemer
   | Close CloseRedeemer
   | Contest ContestRedeemer