Add a new node config entry: TestShelleyHardForkAtVersion

Setting this, e.g.
TestShelleyHardForkAtVersion: 1

Should cause the hard fork to occur when the protocol major version
eraches this value, rather than the default of 2.

This allows a simpler test setup. Otherwise, given that Byron genesis
always starts at protocol version 0, it needs two protocol updates
(includng a node restart) to get to the hard fork.

cardano-config/src/Cardano/Config/Types.hs

@@ -301,10 +301,21 @@ data NodeHardForkProtocolConfiguration =
  -- | For testing purposes we support specifying that the hard fork
  -- happens at an exact epoch number (ie the first epoch of the new era).
  --
- -- Obviously if this is used, all the nodes in the test cluster much be
+ -- Obviously if this is used, all the nodes in the test cluster must be
  -- configured the same, or they will disagree.
  --
  npcTestShelleyHardForkAtEpoch :: Maybe EpochNo
+
+ -- | For testing purposes we support specifying that the hard fork
+ -- happens at a given major protocol version. For example this can be
+ -- used to cause the Shelley hard fork to occur at the transition from
+ -- protocol version 0 to version 1 (rather than the default of from 1 to
+ -- 2) which can make the test setup simpler.
+ --
+ -- Obviously if this is used, all the nodes in the test cluster must be
+ -- configured the same, or they will disagree.
+ --
+ , npcTestShelleyHardForkAtVersion :: Maybe Word
  }
  deriving Show
 
@@ -416,9 +427,11 @@ instance FromJSON NodeConfiguration where
  }
 
  parseHardForkProtocol v = do
- npcTestShelleyHardForkAtEpoch <- v .:? "TestShelleyHardForkAtEpoch"
+ npcTestShelleyHardForkAtEpoch <- v .:? "TestShelleyHardForkAtEpoch"
+ npcTestShelleyHardForkAtVersion <- v .:? "TestShelleyHardForkAtVersion"
  pure NodeHardForkProtocolConfiguration {
- npcTestShelleyHardForkAtEpoch
+ npcTestShelleyHardForkAtEpoch,
+ npcTestShelleyHardForkAtVersion
  }
 
 

cardano-node/src/Cardano/Node/Protocol/Cardano.hs

@@ -121,7 +121,8 @@ mkConsensusProtocolCardano NodeByronProtocolConfiguration {
  npcShelleyMaxSupportedProtocolVersion
  }
  NodeHardForkProtocolConfiguration {
- npcTestShelleyHardForkAtEpoch
+ npcTestShelleyHardForkAtEpoch,
+ npcTestShelleyHardForkAtVersion
  }
  files = do
  byronGenesis <-
@@ -173,7 +174,11 @@ mkConsensusProtocolCardano NodeByronProtocolConfiguration {
  -- Version 1 is Byron with Ouroboros Permissive BFT
  -- Version 2 is Shelley
  --
- Nothing -> Consensus.NoHardCodedTransition 2
+ -- But we also provide an override to allow for simpler test setups
+ -- such as triggering at the 0 -> 1 transition .
+ --
+ Nothing -> Consensus.NoHardCodedTransition
+ (maybe 2 fromIntegral npcTestShelleyHardForkAtVersion)
 
  -- Alternatively, for testing we can transition at a specific epoch.
  --