fixup! BalancingError with explicit script evaluation errors

Author: choener

src/coin-selection/lib/Convex/CoinSelection.hs

@@ -9,6 +9,7 @@
 {-# LANGUAGE MultiWayIf #-}
 {-# LANGUAGE NamedFieldPuns #-}
 {-# LANGUAGE NumericUnderscores #-}
+{-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE TemplateHaskell #-}
 {-# LANGUAGE TupleSections #-}
@@ -141,7 +142,8 @@ import Convex.Utxos (
 import Convex.Utxos qualified as Utxos
 import Convex.Wallet (Wallet)
 import Convex.Wallet qualified as Wallet
-import Data.Aeson (FromJSON (..), ToJSON (..))
+import Data.Aeson (FromJSON (..), Options (sumEncoding), SumEncoding (..), ToJSON (..), withObject, (.:))
+import Data.Aeson.TH (defaultOptions, deriveFromJSON)
 import Data.Bifunctor (Bifunctor (..))
 import Data.Default (Default (..))
 import Data.Function (on)
@@ -222,9 +224,9 @@ bodyError :: C.TxBodyError -> CoinSelectionError
 bodyError = BodyError . Text.pack . C.docToString . C.prettyError
 
 -- Orphan instance, needed to allow full json from here on.
+-- TODO: Check that automatic generation is compatible with cardano-api encoding.
 
-instance FromJSON C.ScriptWitnessIndex where
-  parseJSON = undefined
+$(deriveFromJSON defaultOptions{sumEncoding = TaggedObject{tagFieldName = "kind", contentsFieldName = "value"}} ''C.ScriptWitnessIndex)
 
 -- | Balancing errors, including the *special* 'BalancingScriptExecutionErr'.
 data BalancingError era