IntersectMBO / IntersectMBO/evolution-sdk
improvement: scriptRef size double-counted when UTxO appears in both spent and reference inputs
- Lingua principale
- TypeScript
- Stelle
- 22
- Fork
- 30
- Merge medio
- 5h 29m
- PR unite (30g)
- 12
Descrizione
## Summary
`calculateReferenceScriptFee` receives `[...state.selectedUtxos, ...state.referenceInputs]`. If the same UTxO appears in both arrays (e.g. spent via `collectFrom` and also listed via `readFrom`), its `scriptRef` size is counted **twice**.
The Cardano node deduplicates using `Set.union` before scanning:
```haskell
-- eras/conway/impl/src/Cardano/Ledger/Conway/UTxO.hs
txNonDistinctRefScriptsSize utxo tx = ...
where
inputs = (tx ^. bodyTxL . referenceInputsTxBodyL)
`Set.union` (tx ^. bodyTxL . inputsTxBodyL) -- union deduplicates
```
## Impact
Only affects the edge case where the same UTxO is both spent and read. Over-charges the ref script fee for that UTxO. Safe (node accepts fees above minimum) but imprecise.
## Fix
Deduplicate by UTxO output reference before scanning:
```ts
const seen = new Set()
const deduped = [...state.selectedUtxos, ...state.referenceInputs].filter(utxo => {
const key = `${utxo.txHash}#${utxo.outputIndex}`
if (seen.has(key)) return false
seen.add(key)
return true
})
```
## Affected File
`packages/evolution/src/sdk/builders/phases/FeeCalculation.ts` — the call site that builds the utxo array passed to `calculateReferenceScriptFee`
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Direzione di ricerca
Start in packages/evolution/src/sdk/builders/phases/FeeCalculation.ts at the call site that combines state.selectedUtxos and state.referenceInputs for calculateReferenceScriptFee. Verify how output references are represented, then ensure a UTxO present in both inputs is scanned once; done means the duplicate edge case no longer overcharges the reference script fee.
Scritto dal modello di indicizzazione a partire dal testo della issue.
Valutazione
- Stack tecnologico
- typescript
- Ambito
- blockchain
- Tipo di issue
- Bug
- Difficoltà
- 2/5
- Tempo stimato
- 1-3 ore
- Stato di attività
- Ferma
- Chiarezza
- Specificata chiaramente
- Idoneità per principianti
- 55/100