refactor: allow easier iteration of redeemers

ledger/alonzo/alonzo.go

@@ -17,7 +17,9 @@ package alonzo
 import (
 	"encoding/json"
 	"fmt"
+	"iter"
 	"math/big"
+	"slices"
 
 	"github.com/blinklabs-io/gouroboros/cbor"
 	"github.com/blinklabs-io/gouroboros/ledger/common"
@@ -453,6 +455,40 @@ type AlonzoRedeemer struct {
 
 type AlonzoRedeemers []AlonzoRedeemer
 
+func (r AlonzoRedeemers) Iter() iter.Seq2[common.RedeemerKey, common.RedeemerValue] {
+	return func(yield func(common.RedeemerKey, common.RedeemerValue) bool) {
+		// Sort redeemers
+		sorted := make([]AlonzoRedeemer, len(r))
+		copy(sorted, r)
+		slices.SortFunc(
+			sorted,
+			func(a, b AlonzoRedeemer) int {
+				if a.Tag < b.Tag || (a.Tag == b.Tag && a.Index < b.Index) {
+					return -1
+				}
+				if a.Tag > b.Tag || (a.Tag == b.Tag && a.Index > b.Index) {
+					return 1
+				}
+				return 0
+			},
+		)
+		// Yield keys
+		for _, redeemer := range sorted {
+			tmpKey := common.RedeemerKey{
+				Tag:   redeemer.Tag,
+				Index: redeemer.Index,
+			}
+			tmpVal := common.RedeemerValue{
+				Data:    redeemer.Data,
+				ExUnits: redeemer.ExUnits,
+			}
+			if !yield(tmpKey, tmpVal) {
+				return
+			}
+		}
+	}
+}
+
 func (r AlonzoRedeemers) Indexes(tag common.RedeemerTag) []uint {
 	ret := []uint{}
 	for _, redeemer := range r {
@@ -466,13 +502,16 @@ func (r AlonzoRedeemers) Indexes(tag common.RedeemerTag) []uint {
 func (r AlonzoRedeemers) Value(
 	index uint,
 	tag common.RedeemerTag,
-) (cbor.LazyValue, common.ExUnits) {
+) common.RedeemerValue {
 	for _, redeemer := range r {
 		if redeemer.Tag == tag && uint(redeemer.Index) == index {
-			return redeemer.Data, redeemer.ExUnits
+			return common.RedeemerValue{
+				Data:    redeemer.Data,
+				ExUnits: redeemer.ExUnits,
+			}
 		}
 	}
-	return cbor.LazyValue{}, common.ExUnits{}
+	return common.RedeemerValue{}
 }
 
 type AlonzoTransactionWitnessSet struct {

ledger/alonzo/alonzo_test.go

@@ -164,3 +164,84 @@ func TestAlonzoTransactionOutputToPlutusDataCoinAssets(t *testing.T) {
 		t.Fatalf("did not get expected PlutusData\n     got: %#v\n  wanted: %#v", tmpData, expectedData)
 	}
 }
+
+func TestAlonzoRedeemersIter(t *testing.T) {
+	testRedeemers := AlonzoRedeemers{
+		{
+			Tag:   common.RedeemerTagMint,
+			Index: 2,
+			ExUnits: common.ExUnits{
+				Memory: 1111,
+				Steps:  2222,
+			},
+		},
+		{
+			Tag:   common.RedeemerTagMint,
+			Index: 0,
+			ExUnits: common.ExUnits{
+				Memory: 1111,
+				Steps:  0,
+			},
+		},
+		{
+			Tag:   common.RedeemerTagSpend,
+			Index: 4,
+			ExUnits: common.ExUnits{
+				Memory: 0,
+				Steps:  4444,
+			},
+		},
+	}
+	expectedOrder := []struct {
+		Key   common.RedeemerKey
+		Value common.RedeemerValue
+	}{
+		{
+			Key: common.RedeemerKey{
+				Tag:   common.RedeemerTagSpend,
+				Index: 4,
+			},
+			Value: common.RedeemerValue{
+				ExUnits: common.ExUnits{
+					Memory: 0,
+					Steps:  4444,
+				},
+			},
+		},
+		{
+			Key: common.RedeemerKey{
+				Tag:   common.RedeemerTagMint,
+				Index: 0,
+			},
+			Value: common.RedeemerValue{
+				ExUnits: common.ExUnits{
+					Memory: 1111,
+					Steps:  0,
+				},
+			},
+		},
+		{
+			Key: common.RedeemerKey{
+				Tag:   common.RedeemerTagMint,
+				Index: 2,
+			},
+			Value: common.RedeemerValue{
+				ExUnits: common.ExUnits{
+					Memory: 1111,
+					Steps:  2222,
+				},
+			},
+		},
+	}
+	iterIdx := 0
+	for key, val := range testRedeemers.Iter() {
+		expected := expectedOrder[iterIdx]
+		if !reflect.DeepEqual(key, expected.Key) {
+			t.Fatalf("did not get expected key: got %#v, wanted %#v", key, expected.Key)
+		}
+		if !reflect.DeepEqual(val, expected.Value) {
+			t.Fatalf("did not get expected value: got %#v, wanted %#v", val, expected.Value)
+		}
+		iterIdx++
+	}
+}

ledger/common/redeemer.go

@@ -0,0 +1,42 @@
+// 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 common
+
+import (
+	"github.com/blinklabs-io/gouroboros/cbor"
+)
+
+type RedeemerTag uint8
+
+const (
+	RedeemerTagSpend     RedeemerTag = 0
+	RedeemerTagMint      RedeemerTag = 1
+	RedeemerTagCert      RedeemerTag = 2
+	RedeemerTagReward    RedeemerTag = 3
+	RedeemerTagVoting    RedeemerTag = 4
+	RedeemerTagProposing RedeemerTag = 5
+)
+
+type RedeemerKey struct {
+	cbor.StructAsArray
+	Tag   RedeemerTag
+	Index uint32
+}
+
+type RedeemerValue struct {
+	cbor.StructAsArray
+	Data    cbor.LazyValue
+	ExUnits ExUnits
+}

ledger/common/tx.go

@@ -15,6 +15,8 @@
 package common
 
 import (
+	"iter"
+
 	"github.com/blinklabs-io/gouroboros/cbor"
 	"github.com/blinklabs-io/plutigo/data"
 	utxorpc "github.com/utxorpc/go-codegen/utxorpc/v1alpha/cardano"
@@ -90,7 +92,8 @@ type TransactionWitnessSet interface {
 
 type TransactionWitnessRedeemers interface {
 	Indexes(RedeemerTag) []uint
-	Value(uint, RedeemerTag) (cbor.LazyValue, ExUnits)
+	Value(uint, RedeemerTag) RedeemerValue
+	Iter() iter.Seq2[RedeemerKey, RedeemerValue]
 }
 
 type Utxo struct {

ledger/common/witness.go

@@ -18,17 +18,6 @@ import (
 	"github.com/blinklabs-io/gouroboros/cbor"
 )
 
-type RedeemerTag uint8
-
-const (
-	RedeemerTagSpend     RedeemerTag = 0
-	RedeemerTagMint      RedeemerTag = 1
-	RedeemerTagCert      RedeemerTag = 2
-	RedeemerTagReward    RedeemerTag = 3
-	RedeemerTagVoting    RedeemerTag = 4
-	RedeemerTagProposing RedeemerTag = 5
-)
-
 type VkeyWitness struct {
 	cbor.StructAsArray
 	Vkey      []byte

ledger/conway/conway.go

@@ -17,6 +17,9 @@ package conway
 import (
 	"errors"
 	"fmt"
+	"iter"
+	"maps"
+	"slices"
 
 	"github.com/blinklabs-io/gouroboros/cbor"
 	"github.com/blinklabs-io/gouroboros/ledger/alonzo"
@@ -154,20 +157,8 @@ func (h *ConwayBlockHeader) Era() common.Era {
 	return EraConway
 }
 
-type ConwayRedeemerKey struct {
-	cbor.StructAsArray
-	Tag   common.RedeemerTag
-	Index uint32
-}
-
-type ConwayRedeemerValue struct {
-	cbor.StructAsArray
-	Data    cbor.LazyValue
-	ExUnits common.ExUnits
-}
-
 type ConwayRedeemers struct {
-	Redeemers       map[ConwayRedeemerKey]ConwayRedeemerValue
+	Redeemers       map[common.RedeemerKey]common.RedeemerValue
 	legacyRedeemers alonzo.AlonzoRedeemers
 	legacy          bool
 }
@@ -190,6 +181,32 @@ func (r *ConwayRedeemers) MarshalCBOR() ([]byte, error) {
 	return cbor.Encode(r.Redeemers)
 }
 
+func (r ConwayRedeemers) Iter() iter.Seq2[common.RedeemerKey, common.RedeemerValue] {
+	return func(yield func(common.RedeemerKey, common.RedeemerValue) bool) {
+		// Sort redeemers
+		sorted := slices.Collect(maps.Keys(r.Redeemers))
+		slices.SortFunc(
+			sorted,
+			func(a, b common.RedeemerKey) int {
+				if a.Tag < b.Tag || (a.Tag == b.Tag && a.Index < b.Index) {
+					return -1
+				}
+				if a.Tag > b.Tag || (a.Tag == b.Tag && a.Index > b.Index) {
+					return 1
+				}
+				return 0
+			},
+		)
+		// Yield keys
+		for _, redeemerKey := range sorted {
+			tmpVal := r.Redeemers[redeemerKey]
+			if !yield(redeemerKey, tmpVal) {
+				return
+			}
+		}
+	}
+}
+
 func (r ConwayRedeemers) Indexes(tag common.RedeemerTag) []uint {
 	if r.legacy {
 		return r.legacyRedeemers.Indexes(tag)
@@ -206,18 +223,18 @@ func (r ConwayRedeemers) Indexes(tag common.RedeemerTag) []uint {
 func (r ConwayRedeemers) Value(
 	index uint,
 	tag common.RedeemerTag,
-) (cbor.LazyValue, common.ExUnits) {
+) common.RedeemerValue {
 	if r.legacy {
 		return r.legacyRedeemers.Value(index, tag)
 	}
-	redeemer, ok := r.Redeemers[ConwayRedeemerKey{
+	redeemerVal, ok := r.Redeemers[common.RedeemerKey{
 		Tag:   tag,
 		Index: uint32(index), // #nosec G115
 	}]
 	if ok {
-		return redeemer.Data, redeemer.ExUnits
+		return redeemerVal
 	}
-	return cbor.LazyValue{}, common.ExUnits{}
+	return common.RedeemerValue{}
 }
 
 type ConwayTransactionWitnessSet struct {