feat: Conway era 'Utxo' validation rules (#931)

This also moves the Babbage-era disjoint ref inputs validation to
Conway. It was defined in Babbage in the Haskell code, but it only
actually does anything in the Conway era

Fixes #880

Signed-off-by: Aurora Gaffney <[email protected]>

Author: agaffney

ledger/babbage/errors.go

@@ -16,23 +16,8 @@ package babbage
 
 import (
 	"fmt"
-	"strings"
-
-	"github.com/blinklabs-io/gouroboros/ledger/common"
 )
 
-type NonDisjointRefInputsError struct {
-	Inputs []common.TransactionInput
-}
-
-func (e NonDisjointRefInputsError) Error() string {
-	tmpInputs := make([]string, 0, len(e.Inputs))
-	for idx, tmpInput := range e.Inputs {
-		tmpInputs[idx] = tmpInput.String()
-	}
-	return "non-disjoint reference inputs: " + strings.Join(tmpInputs, ", ")
-}
-
 type TooManyCollateralInputsError struct {
 	Provided uint
 	Max      uint

ledger/babbage/rules.go

@@ -26,7 +26,6 @@ import (
 )
 
 var UtxoValidationRules = []common.UtxoValidationRuleFunc{
-	UtxoValidateDisjointRefInputs,
 	UtxoValidateOutsideValidityIntervalUtxo,
 	UtxoValidateInputSetEmptyUtxo,
 	UtxoValidateFeeTooSmallUtxo,
@@ -46,24 +45,6 @@ var UtxoValidationRules = []common.UtxoValidationRuleFunc{
 	UtxoValidateTooManyCollateralInputs,
 }
 
-func UtxoValidateDisjointRefInputs(tx common.Transaction, slot uint64, ls common.LedgerState, pp common.ProtocolParameters) error {
-	commonInputs := []common.TransactionInput{}
-	for _, refInput := range tx.ReferenceInputs() {
-		for _, input := range tx.Inputs() {
-			if refInput.String() != input.String() {
-				continue
-			}
-			commonInputs = append(commonInputs, input)
-		}
-	}
-	if len(commonInputs) == 0 {
-		return nil
-	}
-	return NonDisjointRefInputsError{
-		Inputs: commonInputs,
-	}
-}
-
 func UtxoValidateOutsideValidityIntervalUtxo(tx common.Transaction, slot uint64, ls common.LedgerState, pp common.ProtocolParameters) error {
 	return allegra.UtxoValidateOutsideValidityIntervalUtxo(tx, slot, ls, pp)
 }

ledger/babbage/rules_test.go

@@ -1290,77 +1290,6 @@ func TestUtxoValidateExUnitsTooBigUtxo(t *testing.T) {
 	)
 }
 
-func TestUtxoValidateDisjointRefInputs(t *testing.T) {
-	testInputTxId := "d228b482a1aae768e4a796380f49e021d9c21f70d3c12cb186b188dedfc0ee22"
-	testTx := &babbage.BabbageTransaction{
-		Body: babbage.BabbageTransactionBody{},
-	}
-	testLedgerState := testLedgerState{}
-	testSlot := uint64(0)
-	testProtocolParams := &babbage.BabbageProtocolParameters{}
-	// Non-disjoint ref inputs
-	t.Run(
-		"non-disjoint ref inputs",
-		func(t *testing.T) {
-			testTx.Body.TxInputs = shelley.NewShelleyTransactionInputSet(
-				[]shelley.ShelleyTransactionInput{
-					shelley.NewShelleyTransactionInput(testInputTxId, 0),
-				},
-			)
-			testTx.Body.TxReferenceInputs = []shelley.ShelleyTransactionInput{
-				shelley.NewShelleyTransactionInput(testInputTxId, 0),
-			}
-			err := babbage.UtxoValidateDisjointRefInputs(
-				testTx,
-				testSlot,
-				testLedgerState,
-				testProtocolParams,
-			)
-			if err == nil {
-				t.Errorf(
-					"UtxoValidateDisjointRefInputs should fail when inputs and ref inputs are duplicated",
-				)
-				return
-			}
-			testErrType := babbage.NonDisjointRefInputsError{}
-			assert.IsType(
-				t,
-				testErrType,
-				err,
-				"did not get expected error type: got %T, wanted %T",
-				err,
-				testErrType,
-			)
-		},
-	)
-	// Disjoint ref inputs
-	t.Run(
-		"disjoint ref inputs",
-		func(t *testing.T) {
-			testTx.Body.TxInputs = shelley.NewShelleyTransactionInputSet(
-				[]shelley.ShelleyTransactionInput{
-					shelley.NewShelleyTransactionInput(testInputTxId, 0),
-				},
-			)
-			testTx.Body.TxReferenceInputs = []shelley.ShelleyTransactionInput{
-				shelley.NewShelleyTransactionInput(testInputTxId, 1),
-			}
-			err := babbage.UtxoValidateDisjointRefInputs(
-				testTx,
-				testSlot,
-				testLedgerState,
-				testProtocolParams,
-			)
-			if err != nil {
-				t.Errorf(
-					"UtxoValidateDisjointRefInputs should succeed when inputs and ref inputs are not duplicated\n  got error: %v",
-					err,
-				)
-			}
-		},
-	)
-}
-
 func TestUtxoValidateCollateralEqBalance(t *testing.T) {
 	testInputTxId := "d228b482a1aae768e4a796380f49e021d9c21f70d3c12cb186b188dedfc0ee22"
 	var testInputAmount uint64 = 20_000_000

ledger/conway/conway.go

@@ -236,6 +236,15 @@ type ConwayTransactionInputSet struct {
 	items []shelley.ShelleyTransactionInput
 }
 
+func NewConwayTransactionInputSet(
+	items []shelley.ShelleyTransactionInput,
+) ConwayTransactionInputSet {
+	s := ConwayTransactionInputSet{
+		items: items,
+	}
+	return s
+}
+
 func (s *ConwayTransactionInputSet) UnmarshalCBOR(data []byte) error {
 	// This overrides the Shelley behavior that explicitly disallowed tag-wrapped sets
 	var tmpData []shelley.ShelleyTransactionInput
@@ -250,6 +259,11 @@ func (s *ConwayTransactionInputSet) Items() []shelley.ShelleyTransactionInput {
 	return s.items
 }
 
+func (s *ConwayTransactionInputSet) SetItems(items []shelley.ShelleyTransactionInput) {
+	s.items = make([]shelley.ShelleyTransactionInput, len(items))
+	copy(s.items, items)
+}
+
 type ConwayTransactionBody struct {
 	babbage.BabbageTransactionBody
 	TxInputs               ConwayTransactionInputSet  `cbor:"0,keyasint,omitempty"`

ledger/conway/errors.go

@@ -0,0 +1,33 @@
+// Copyright 2025 Blink Labs Software
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package conway
+
+import (
+	"strings"
+
+	"github.com/blinklabs-io/gouroboros/ledger/common"
+)
+
+type NonDisjointRefInputsError struct {
+	Inputs []common.TransactionInput
+}
+
+func (e NonDisjointRefInputsError) Error() string {
+	tmpInputs := make([]string, 0, len(e.Inputs))
+	for idx, tmpInput := range e.Inputs {
+		tmpInputs[idx] = tmpInput.String()
+	}
+	return "non-disjoint reference inputs: " + strings.Join(tmpInputs, ", ")
+}