tx-generator: stop supporting Byron and use more recent API way to handle eras

[smelc]

Note

On top of #6085

Description

• Stop using IsShelleyBasedEra, which is not the usual way to interact with cardano-api anymore.
• Use a ShelleyBasedEra era witness instead.
• As a consequence, this avoids picking the era in many places with shelleyBasedEra. Passing the witness around makes sure the era being used is consistent.
• This also simplifies the code, as you don't need type applications anymore.

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• CI passes. See note on CI. The following CI checks are required:
  • Code is linted with hlint. See .github/workflows/check-hlint.yml to get the hlint version
  • Code is formatted with stylish-haskell. See .github/workflows/stylish-haskell.yml to get the stylish-haskell version
• Self-reviewed the diff

[NadiaYvette]

ScopedTypeVariables could also be dropped, not that this should be held up for that.

[smelc]

Removed 👍

[NadiaYvette]

There's a chance to switch return to pure in selectCollateralFunds and interpretPayMode if it wouldn't slow you down.

[smelc]

Changed 👍

[NadiaYvette]

If you can sneak more cleanups in here, that would be great e.g.

diff --git a/bench/tx-generator/src/Cardano/TxGenerator/Genesis.hs b/bench/tx-generator/src/Cardano/TxGenerator/Genesis.hs
index f412dcdc7..c401bd1c7 100644
--- a/bench/tx-generator/src/Cardano/TxGenerator/Genesis.hs
+++ b/bench/tx-generator/src/Cardano/TxGenerator/Genesis.hs
@@ -1,7 +1,6 @@
-{-# LANGUAGE DerivingStrategies #-}
 {-# LANGUAGE NamedFieldPuns #-}
-{-# LANGUAGE RankNTypes #-}
-{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TupleSections #-}
+{-# LANGUAGE ViewPatterns #-}
 
 {- HLINT ignore "Use map" -}
 
@@ -49,9 +48,8 @@ genesisSecureInitialFund :: ()
 genesisSecureInitialFund sbe networkId genesis srcKey destKey TxGenTxParams{txParamFee, txParamTTL}
   = case genesisInitialFundForKey sbe networkId genesis srcKey of
       Nothing             -> Left $ TxGenError "genesisSecureInitialFund: no fund found for given key in genesis"
-      Just (_, lovelace)  ->
-        let txOutValue = lovelaceToTxOutValue sbe $ lovelace - txParamFee
-        in genesisExpenditure sbe networkId srcKey destAddr txOutValue txParamFee txParamTTL destKey
+      Just (_, lovelaceToTxOutValue sbe . subtract txParamFee -> txOutValue) ->
+        genesisExpenditure sbe networkId srcKey destAddr txOutValue txParamFee txParamTTL destKey
   where
     destAddr = keyAddress sbe networkId destKey
 
@@ -128,7 +126,7 @@ mkGenesisTransaction sbe key ttl fee txins txouts
       (createAndValidateTransactionBody sbe txBodyContent)
  where
   txBodyContent = defaultTxBodyContent sbe
-    & setTxIns (zip txins $ repeat $ BuildTxWith $ KeyWitness KeyWitnessForSpending)
+    & setTxIns (map (, BuildTxWith $ KeyWitness KeyWitnessForSpending) txins)
     & setTxOuts txouts
     & setTxFee (mkTxFee sbe fee)
     & setTxValidityLowerBound TxValidityNoLowerBound

No need to hold up the show if it's too much of a bother.

[NadiaYvette]

This could also be worth getting in there too:

@@ -75,9 +73,9 @@ genesisInitialFundForKey :: ()
   -> SigningKey PaymentKey
   -> Maybe (AddressInEra era, L.Coin)
 genesisInitialFundForKey sbe networkId genesis key
-  = find (isTxOutForKey . fst) (genesisInitialFunds sbe networkId genesis)
+  = find isTxOutForKey $ genesisInitialFunds sbe networkId genesis
  where
-  isTxOutForKey = (keyAddress sbe networkId key ==)
+  isTxOutForKey = (keyAddress sbe networkId key ==) . fst
 
 genesisTxInput ::
      NetworkId

[smelc]

@NadiaYvette> I did the changes, except for the usage of ViewPatterns. I think ViewPatterns is a niche extension that augments the entry-level to a codebase, usually for little gain. Feel free to amend yourself!

[NadiaYvette]

This is great! I think ScopedTypeVariables can go too wrt. extensions.

[smelc]

Removed 👍

[NadiaYvette]

This is great too. I can't do an approve/etc. yet because it says it's WIP & whatever went on with the flake and garnix checks, but the instant those bits are all cleared up, I'm ready to hit the approve button.

[smelc]

@NadiaYvette> I acted on your comments and this is now ready to go IMO.

You can ignore the Garnix and flake.nix checks. Those are not required yet as they are still being worked on.

[smelc]

Convert to draft until @mgmeier confirms that we can drop Byron support.