PlutusV4 script construction not implemented in old API (Plutus/Internal/Script.hs:1302)

[Jimbo4350]

Problem

cardano-api/src/Cardano/Api/Plutus/Internal/Script.hs:1302 contains a placeholder error for PlutusV4 script construction in the old API:

toShelleyScript
  ( ScriptInEra
      _langInEra
      ( PlutusScript
          PlutusScriptV4
          (PlutusScriptSerialised _script)
        )
    ) = error "toShelleyScript: PlutusV4 not implemented yet."

The intended implementation exists as a commented-out block at lines 1304–1310:

-- TODO: Ledger needs to introduce a plutusV4 constructor
-- case langInEra of
--   PlutusScriptV4InConway ->
--     Alonzo.PlutusScript . Conway.ConwayPlutusV3 . Plutus.Plutus $ Plutus.PlutusBinary script
--   PlutusScriptV4InDijkstra ->
--     Alonzo.PlutusScript . Dijkstra.MkDijkstraPlutusScript . Conway.ConwayPlutusV3 . Plutus.Plutus $
--       Plutus.PlutusBinary script

Blocker

Ledger needs to expose a PlutusV4 script constructor on Dijkstra (Dijkstra.MkDijkstraPlutusScript / DijkstraPlutusV4) before this can be implemented in cardano-api.

Related

A structurally similar PlutusV4 stub exists at cardano-api/src/Cardano/Api/Experimental/Tx/Internal/AnyWitness.hs:128:

getPlutusDatum L.SPlutusV4 (SpendingScriptDatum _d) = error "TODO Dijkstra: getPlutusDatum: era not supported"

This one doesn't block on ledger — PlutusScriptDatumF L.PlutusV4 SpendingScript = Maybe HashableScriptData (CIP-69 style, matches V3), so the fix is likely a one-liner:

getPlutusDatum L.SPlutusV4 (SpendingScriptDatum d) = d

It is phrased as a Dijkstra placeholder (and unified under TODO Dijkstra: in #1187 for greppability) but it is really a PlutusV4 gap and can be fixed independently of ledger work.

Context

#1187 unified all Dijkstra-era placeholder messages in cardano-api under the single greppable token TODO Dijkstra:. This PlutusV4 stub was intentionally excluded because it blocks on ledger work rather than cardano-api work.