fix: implement IDSet (registryEntryHolderSet) decoder/encoder

- Replace old broken RegistryEntryHolderSetDecoder with correct varint
  discriminator: id != 0 returns raw ID, id == 0 decodes string base
- Add RegistryEntryHolderSetEncoder using type switch (string/int32)
- Add NonErroringIndex to proto_base (zero-fallback index lookup)
- DeclareRecipes now fails with index not found (mapper) instead of to do

mc/proto_base/base_types.go

@@ -262,6 +262,12 @@ func ErroringIndex[K comparable, V any, M map[K]V](m M, i K) (v V, err error) {
 	return
 }
 
+// NonErroringIndex looks up key k in map m and returns the zero value without error if not found.
+func NonErroringIndex[K comparable, V any, M map[K]V](m M, i K) (v V, err error) {
+	v, _ = m[i]
+	return
+}
+
 // EncodeDecodeAble is implemented by types that can be encoded and decoded for
 // Minecraft protocol packets.
 type EncodeDecodeAble interface {

mc/proto_generated/v1_12_2/proto.go

@@ -1,6 +1,6 @@
 // Code generated by strom. DO NOT EDIT.
 // source: minecraft-data/pc/1.12.2/protocol.json (sha256:21c57208db654a5e14a34cb696570080df179c5c642e53b16120399eee9232be)
-// version: v0.6.6-0.20260805170503-1d8f70c7fdae+dirty (go1.26.2)
+// version: v0.6.6-0.20260805173638-56ac8e154ea1+dirty (go1.26.2)
 package v1_12_2
 
 import (

mc/proto_generated/v1_14_4/proto.go

@@ -1,6 +1,6 @@
 // Code generated by strom. DO NOT EDIT.
 // source: minecraft-data/pc/1.14.4/protocol.json (sha256:b6edff5abaaf234037b5019024d749e27e746250a23253bb4ad77d8f76e93167)
-// version: v0.6.6-0.20260805170503-1d8f70c7fdae+dirty (go1.26.2)
+// version: v0.6.6-0.20260805173638-56ac8e154ea1+dirty (go1.26.2)
 package v1_14_4
 
 import (

mc/proto_generated/v1_16_5/proto.go

@@ -1,6 +1,6 @@
 // Code generated by strom. DO NOT EDIT.
 // source: minecraft-data/pc/1.16.2/protocol.json (sha256:d96a3c5a7a7ddf2105e23990c2471b3aeafe4a6975e0c9d7d7943b599af9dfb3)
-// version: v0.6.6-0.20260805170503-1d8f70c7fdae+dirty (go1.26.2)
+// version: v0.6.6-0.20260805173638-56ac8e154ea1+dirty (go1.26.2)
 package v1_16_5
 
 import (

mc/proto_generated/v1_21_11/proto.go

@@ -1,6 +1,6 @@
 // Code generated by strom. DO NOT EDIT.
 // source: minecraft-data/pc/1.21.11/protocol.json (sha256:97d2726cce3a39cc967a954f27f4ebf029ec3f0f655bb21942aab8745d13cdab)
-// version: v0.6.6-0.20260805170503-1d8f70c7fdae+dirty (go1.26.2)
+// version: v0.6.6-0.20260805173638-56ac8e154ea1+dirty (go1.26.2)
 package v1_21_11
 
 import (
@@ -901,11 +901,42 @@ type IDSet struct {
 }
 
 func (ret *IDSet) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var IDSetId int32
+	IDSetId, err = proto_base.DecodeVarInt(r)
+	if err != nil {
+		return
+	}
+	if IDSetId != 0 {
+		ret.Val = IDSetId
+	} else {
+		var IDSetResult string
+		IDSetResult, err = proto_base.DecodeString(r)
+		if err != nil {
+			return
+		}
+		ret.Val = IDSetResult
+	}
 	return
 }
 func (ret *IDSet) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	switch IDSetKnownType := ret.Val.(type) {
+	case string:
+		err = proto_base.EncodeVarInt(w, 0)
+		if err != nil {
+			return
+		}
+		err = proto_base.EncodeString(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	case int32:
+		err = proto_base.EncodeVarInt(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	default:
+		err = proto_base.BadTypeError
+	}
 	return
 }
 
@@ -965,11 +996,115 @@ type ItemBlockPredicate struct {
 }
 
 func (ret *ItemBlockPredicate) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var ItemBlockPredicateBlockSetPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicateBlockSetPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicateBlockSetPresent {
+		var ItemBlockPredicateBlockSetPresentValue any
+		var ItemBlockPredicateBlockSetId int32
+		ItemBlockPredicateBlockSetId, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		if ItemBlockPredicateBlockSetId != 0 {
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetId
+		} else {
+			var ItemBlockPredicateBlockSetResult string
+			ItemBlockPredicateBlockSetResult, err = proto_base.DecodeString(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetResult
+		}
+		ret.BlockSet = &ItemBlockPredicateBlockSetPresentValue
+	}
+	var ItemBlockPredicatePropertiesPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicatePropertiesPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicatePropertiesPresent {
+		var ItemBlockPredicatePropertiesPresentValue []ItemBlockProperty
+		var lItemBlockPredicateProperties int32
+		lItemBlockPredicateProperties, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		ItemBlockPredicatePropertiesPresentValue = []ItemBlockProperty{}
+		for range lItemBlockPredicateProperties {
+			var ItemBlockPredicatePropertiesElement ItemBlockProperty
+			err = ItemBlockPredicatePropertiesElement.Decode(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicatePropertiesPresentValue = append(ItemBlockPredicatePropertiesPresentValue, ItemBlockPredicatePropertiesElement)
+		}
+		ret.Properties = &ItemBlockPredicatePropertiesPresentValue
+	}
+	err = ret.Nbt.Decode(r)
+	if err != nil {
+		return
+	}
+	err = ret.Components.Decode(r)
+	if err != nil {
+		return
+	}
 	return
 }
 func (ret *ItemBlockPredicate) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	err = binary.Write(w, binary.BigEndian, ret.BlockSet != nil)
+	if err != nil {
+		return
+	}
+	if ret.BlockSet != nil {
+		switch ItemBlockPredicateBlockSetKnownType := (*ret.BlockSet).(type) {
+		case string:
+			err = proto_base.EncodeVarInt(w, 0)
+			if err != nil {
+				return
+			}
+			err = proto_base.EncodeString(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		case int32:
+			err = proto_base.EncodeVarInt(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		default:
+			err = proto_base.BadTypeError
+		}
+	}
+	err = binary.Write(w, binary.BigEndian, ret.Properties != nil)
+	if err != nil {
+		return
+	}
+	if ret.Properties != nil {
+		err = proto_base.EncodeVarInt(w, int32(len(*ret.Properties)))
+		if err != nil {
+			return
+		}
+		for iItemBlockPredicateProperties := range len(*ret.Properties) {
+			ItemBlockPredicatePropertiesInnerEncTmp := (*ret.Properties)[iItemBlockPredicateProperties]
+			err = ItemBlockPredicatePropertiesInnerEncTmp.Encode(w)
+			if err != nil {
+				return
+			}
+		}
+	}
+	ItemBlockPredicateNbtEncTmp := ret.Nbt
+	err = ItemBlockPredicateNbtEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
+	ItemBlockPredicateComponentsEncTmp := ret.Components
+	err = ItemBlockPredicateComponentsEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
 	return
 }
 

mc/proto_generated/v1_21_8/proto.go

@@ -1,6 +1,6 @@
 // Code generated by strom. DO NOT EDIT.
 // source: minecraft-data/pc/1.21.8/protocol.json (sha256:930fbb4c69fd2ecadddcee3c38d3f02908adc23b54b707cb21112e7ab1e9dba1)
-// version: v0.6.6-0.20260805170503-1d8f70c7fdae+dirty (go1.26.2)
+// version: v0.6.6-0.20260805173638-56ac8e154ea1+dirty (go1.26.2)
 package v1_21_8
 
 import (
@@ -525,11 +525,42 @@ type IDSet struct {
 }
 
 func (ret *IDSet) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var IDSetId int32
+	IDSetId, err = proto_base.DecodeVarInt(r)
+	if err != nil {
+		return
+	}
+	if IDSetId != 0 {
+		ret.Val = IDSetId
+	} else {
+		var IDSetResult string
+		IDSetResult, err = proto_base.DecodeString(r)
+		if err != nil {
+			return
+		}
+		ret.Val = IDSetResult
+	}
 	return
 }
 func (ret *IDSet) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	switch IDSetKnownType := ret.Val.(type) {
+	case string:
+		err = proto_base.EncodeVarInt(w, 0)
+		if err != nil {
+			return
+		}
+		err = proto_base.EncodeString(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	case int32:
+		err = proto_base.EncodeVarInt(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	default:
+		err = proto_base.BadTypeError
+	}
 	return
 }
 
@@ -589,11 +620,115 @@ type ItemBlockPredicate struct {
 }
 
 func (ret *ItemBlockPredicate) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var ItemBlockPredicateBlockSetPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicateBlockSetPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicateBlockSetPresent {
+		var ItemBlockPredicateBlockSetPresentValue any
+		var ItemBlockPredicateBlockSetId int32
+		ItemBlockPredicateBlockSetId, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		if ItemBlockPredicateBlockSetId != 0 {
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetId
+		} else {
+			var ItemBlockPredicateBlockSetResult string
+			ItemBlockPredicateBlockSetResult, err = proto_base.DecodeString(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetResult
+		}
+		ret.BlockSet = &ItemBlockPredicateBlockSetPresentValue
+	}
+	var ItemBlockPredicatePropertiesPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicatePropertiesPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicatePropertiesPresent {
+		var ItemBlockPredicatePropertiesPresentValue []ItemBlockProperty
+		var lItemBlockPredicateProperties int32
+		lItemBlockPredicateProperties, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		ItemBlockPredicatePropertiesPresentValue = []ItemBlockProperty{}
+		for range lItemBlockPredicateProperties {
+			var ItemBlockPredicatePropertiesElement ItemBlockProperty
+			err = ItemBlockPredicatePropertiesElement.Decode(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicatePropertiesPresentValue = append(ItemBlockPredicatePropertiesPresentValue, ItemBlockPredicatePropertiesElement)
+		}
+		ret.Properties = &ItemBlockPredicatePropertiesPresentValue
+	}
+	err = ret.Nbt.Decode(r)
+	if err != nil {
+		return
+	}
+	err = ret.Components.Decode(r)
+	if err != nil {
+		return
+	}
 	return
 }
 func (ret *ItemBlockPredicate) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	err = binary.Write(w, binary.BigEndian, ret.BlockSet != nil)
+	if err != nil {
+		return
+	}
+	if ret.BlockSet != nil {
+		switch ItemBlockPredicateBlockSetKnownType := (*ret.BlockSet).(type) {
+		case string:
+			err = proto_base.EncodeVarInt(w, 0)
+			if err != nil {
+				return
+			}
+			err = proto_base.EncodeString(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		case int32:
+			err = proto_base.EncodeVarInt(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		default:
+			err = proto_base.BadTypeError
+		}
+	}
+	err = binary.Write(w, binary.BigEndian, ret.Properties != nil)
+	if err != nil {
+		return
+	}
+	if ret.Properties != nil {
+		err = proto_base.EncodeVarInt(w, int32(len(*ret.Properties)))
+		if err != nil {
+			return
+		}
+		for iItemBlockPredicateProperties := range len(*ret.Properties) {
+			ItemBlockPredicatePropertiesInnerEncTmp := (*ret.Properties)[iItemBlockPredicateProperties]
+			err = ItemBlockPredicatePropertiesInnerEncTmp.Encode(w)
+			if err != nil {
+				return
+			}
+		}
+	}
+	ItemBlockPredicateNbtEncTmp := ret.Nbt
+	err = ItemBlockPredicateNbtEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
+	ItemBlockPredicateComponentsEncTmp := ret.Components
+	err = ItemBlockPredicateComponentsEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
 	return
 }
 

mc/proto_generated/v1_21_9/proto.go

@@ -1,6 +1,6 @@
 // Code generated by strom. DO NOT EDIT.
 // source: minecraft-data/pc/1.21.9/protocol.json (sha256:9861cee397931c678c3b1837dcdf82e3fc885442c6bd0e4a60522fbf26653e59)
-// version: v0.6.6-0.20260805170503-1d8f70c7fdae+dirty (go1.26.2)
+// version: v0.6.6-0.20260805173638-56ac8e154ea1+dirty (go1.26.2)
 package v1_21_9
 
 import (
@@ -807,11 +807,42 @@ type IDSet struct {
 }
 
 func (ret *IDSet) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var IDSetId int32
+	IDSetId, err = proto_base.DecodeVarInt(r)
+	if err != nil {
+		return
+	}
+	if IDSetId != 0 {
+		ret.Val = IDSetId
+	} else {
+		var IDSetResult string
+		IDSetResult, err = proto_base.DecodeString(r)
+		if err != nil {
+			return
+		}
+		ret.Val = IDSetResult
+	}
 	return
 }
 func (ret *IDSet) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	switch IDSetKnownType := ret.Val.(type) {
+	case string:
+		err = proto_base.EncodeVarInt(w, 0)
+		if err != nil {
+			return
+		}
+		err = proto_base.EncodeString(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	case int32:
+		err = proto_base.EncodeVarInt(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	default:
+		err = proto_base.BadTypeError
+	}
 	return
 }
 
@@ -871,11 +902,115 @@ type ItemBlockPredicate struct {
 }
 
 func (ret *ItemBlockPredicate) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var ItemBlockPredicateBlockSetPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicateBlockSetPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicateBlockSetPresent {
+		var ItemBlockPredicateBlockSetPresentValue any
+		var ItemBlockPredicateBlockSetId int32
+		ItemBlockPredicateBlockSetId, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		if ItemBlockPredicateBlockSetId != 0 {
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetId
+		} else {
+			var ItemBlockPredicateBlockSetResult string
+			ItemBlockPredicateBlockSetResult, err = proto_base.DecodeString(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetResult
+		}
+		ret.BlockSet = &ItemBlockPredicateBlockSetPresentValue
+	}
+	var ItemBlockPredicatePropertiesPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicatePropertiesPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicatePropertiesPresent {
+		var ItemBlockPredicatePropertiesPresentValue []ItemBlockProperty
+		var lItemBlockPredicateProperties int32
+		lItemBlockPredicateProperties, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		ItemBlockPredicatePropertiesPresentValue = []ItemBlockProperty{}
+		for range lItemBlockPredicateProperties {
+			var ItemBlockPredicatePropertiesElement ItemBlockProperty
+			err = ItemBlockPredicatePropertiesElement.Decode(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicatePropertiesPresentValue = append(ItemBlockPredicatePropertiesPresentValue, ItemBlockPredicatePropertiesElement)
+		}
+		ret.Properties = &ItemBlockPredicatePropertiesPresentValue
+	}
+	err = ret.Nbt.Decode(r)
+	if err != nil {
+		return
+	}
+	err = ret.Components.Decode(r)
+	if err != nil {
+		return
+	}
 	return
 }
 func (ret *ItemBlockPredicate) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	err = binary.Write(w, binary.BigEndian, ret.BlockSet != nil)
+	if err != nil {
+		return
+	}
+	if ret.BlockSet != nil {
+		switch ItemBlockPredicateBlockSetKnownType := (*ret.BlockSet).(type) {
+		case string:
+			err = proto_base.EncodeVarInt(w, 0)
+			if err != nil {
+				return
+			}
+			err = proto_base.EncodeString(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		case int32:
+			err = proto_base.EncodeVarInt(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		default:
+			err = proto_base.BadTypeError
+		}
+	}
+	err = binary.Write(w, binary.BigEndian, ret.Properties != nil)
+	if err != nil {
+		return
+	}
+	if ret.Properties != nil {
+		err = proto_base.EncodeVarInt(w, int32(len(*ret.Properties)))
+		if err != nil {
+			return
+		}
+		for iItemBlockPredicateProperties := range len(*ret.Properties) {
+			ItemBlockPredicatePropertiesInnerEncTmp := (*ret.Properties)[iItemBlockPredicateProperties]
+			err = ItemBlockPredicatePropertiesInnerEncTmp.Encode(w)
+			if err != nil {
+				return
+			}
+		}
+	}
+	ItemBlockPredicateNbtEncTmp := ret.Nbt
+	err = ItemBlockPredicateNbtEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
+	ItemBlockPredicateComponentsEncTmp := ret.Components
+	err = ItemBlockPredicateComponentsEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
 	return
 }
 

mc/proto_generated/v1_8/proto.go

@@ -1,6 +1,6 @@
 // Code generated by strom. DO NOT EDIT.
 // source: minecraft-data/pc/1.8/protocol.json (sha256:79fe774bfc255dd281899c004fbb9c7adc40fb107de9353da1dd0371ea4b53af)
-// version: v0.6.6-0.20260805170503-1d8f70c7fdae+dirty (go1.26.2)
+// version: v0.6.6-0.20260805173638-56ac8e154ea1+dirty (go1.26.2)
 package v1_8
 
 import (

mc/proto_generated/v26_1/proto.go

@@ -1,6 +1,6 @@
 // Code generated by strom. DO NOT EDIT.
 // source: minecraft-data/pc/26.1/protocol.json (sha256:dfb6318886cd3ceab617f75ac05e24f9836a64501d60551071289b904ebfc389)
-// version: v0.6.6-0.20260805170503-1d8f70c7fdae+dirty (go1.26.2)
+// version: v0.6.6-0.20260805173638-56ac8e154ea1+dirty (go1.26.2)
 package v26_1
 
 import (
@@ -901,11 +901,42 @@ type IDSet struct {
 }
 
 func (ret *IDSet) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var IDSetId int32
+	IDSetId, err = proto_base.DecodeVarInt(r)
+	if err != nil {
+		return
+	}
+	if IDSetId != 0 {
+		ret.Val = IDSetId
+	} else {
+		var IDSetResult string
+		IDSetResult, err = proto_base.DecodeString(r)
+		if err != nil {
+			return
+		}
+		ret.Val = IDSetResult
+	}
 	return
 }
 func (ret *IDSet) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	switch IDSetKnownType := ret.Val.(type) {
+	case string:
+		err = proto_base.EncodeVarInt(w, 0)
+		if err != nil {
+			return
+		}
+		err = proto_base.EncodeString(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	case int32:
+		err = proto_base.EncodeVarInt(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	default:
+		err = proto_base.BadTypeError
+	}
 	return
 }
 
@@ -965,11 +996,115 @@ type ItemBlockPredicate struct {
 }
 
 func (ret *ItemBlockPredicate) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var ItemBlockPredicateBlockSetPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicateBlockSetPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicateBlockSetPresent {
+		var ItemBlockPredicateBlockSetPresentValue any
+		var ItemBlockPredicateBlockSetId int32
+		ItemBlockPredicateBlockSetId, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		if ItemBlockPredicateBlockSetId != 0 {
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetId
+		} else {
+			var ItemBlockPredicateBlockSetResult string
+			ItemBlockPredicateBlockSetResult, err = proto_base.DecodeString(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetResult
+		}
+		ret.BlockSet = &ItemBlockPredicateBlockSetPresentValue
+	}
+	var ItemBlockPredicatePropertiesPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicatePropertiesPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicatePropertiesPresent {
+		var ItemBlockPredicatePropertiesPresentValue []ItemBlockProperty
+		var lItemBlockPredicateProperties int32
+		lItemBlockPredicateProperties, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		ItemBlockPredicatePropertiesPresentValue = []ItemBlockProperty{}
+		for range lItemBlockPredicateProperties {
+			var ItemBlockPredicatePropertiesElement ItemBlockProperty
+			err = ItemBlockPredicatePropertiesElement.Decode(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicatePropertiesPresentValue = append(ItemBlockPredicatePropertiesPresentValue, ItemBlockPredicatePropertiesElement)
+		}
+		ret.Properties = &ItemBlockPredicatePropertiesPresentValue
+	}
+	err = ret.Nbt.Decode(r)
+	if err != nil {
+		return
+	}
+	err = ret.Components.Decode(r)
+	if err != nil {
+		return
+	}
 	return
 }
 func (ret *ItemBlockPredicate) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	err = binary.Write(w, binary.BigEndian, ret.BlockSet != nil)
+	if err != nil {
+		return
+	}
+	if ret.BlockSet != nil {
+		switch ItemBlockPredicateBlockSetKnownType := (*ret.BlockSet).(type) {
+		case string:
+			err = proto_base.EncodeVarInt(w, 0)
+			if err != nil {
+				return
+			}
+			err = proto_base.EncodeString(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		case int32:
+			err = proto_base.EncodeVarInt(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		default:
+			err = proto_base.BadTypeError
+		}
+	}
+	err = binary.Write(w, binary.BigEndian, ret.Properties != nil)
+	if err != nil {
+		return
+	}
+	if ret.Properties != nil {
+		err = proto_base.EncodeVarInt(w, int32(len(*ret.Properties)))
+		if err != nil {
+			return
+		}
+		for iItemBlockPredicateProperties := range len(*ret.Properties) {
+			ItemBlockPredicatePropertiesInnerEncTmp := (*ret.Properties)[iItemBlockPredicateProperties]
+			err = ItemBlockPredicatePropertiesInnerEncTmp.Encode(w)
+			if err != nil {
+				return
+			}
+		}
+	}
+	ItemBlockPredicateNbtEncTmp := ret.Nbt
+	err = ItemBlockPredicateNbtEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
+	ItemBlockPredicateComponentsEncTmp := ret.Components
+	err = ItemBlockPredicateComponentsEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
 	return
 }
 

mc/proto_generated/v26_2/proto.go

@@ -1,6 +1,6 @@
 // Code generated by strom. DO NOT EDIT.
 // source: minecraft-data/pc/26.2/protocol.json (sha256:7ba66411adcc68a668f38211e1b00eeb386a345d5eb16fadd6dc1c7f94bb175f)
-// version: v0.6.6-0.20260805170503-1d8f70c7fdae+dirty (go1.26.2)
+// version: v0.6.6-0.20260805173638-56ac8e154ea1+dirty (go1.26.2)
 package v26_2
 
 import (
@@ -901,11 +901,42 @@ type IDSet struct {
 }
 
 func (ret *IDSet) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var IDSetId int32
+	IDSetId, err = proto_base.DecodeVarInt(r)
+	if err != nil {
+		return
+	}
+	if IDSetId != 0 {
+		ret.Val = IDSetId
+	} else {
+		var IDSetResult string
+		IDSetResult, err = proto_base.DecodeString(r)
+		if err != nil {
+			return
+		}
+		ret.Val = IDSetResult
+	}
 	return
 }
 func (ret *IDSet) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	switch IDSetKnownType := ret.Val.(type) {
+	case string:
+		err = proto_base.EncodeVarInt(w, 0)
+		if err != nil {
+			return
+		}
+		err = proto_base.EncodeString(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	case int32:
+		err = proto_base.EncodeVarInt(w, IDSetKnownType)
+		if err != nil {
+			return
+		}
+	default:
+		err = proto_base.BadTypeError
+	}
 	return
 }
 
@@ -965,11 +996,115 @@ type ItemBlockPredicate struct {
 }
 
 func (ret *ItemBlockPredicate) Decode(r io.ReadSeeker) (err error) {
-	err = proto_base.ToDoError
+	var ItemBlockPredicateBlockSetPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicateBlockSetPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicateBlockSetPresent {
+		var ItemBlockPredicateBlockSetPresentValue any
+		var ItemBlockPredicateBlockSetId int32
+		ItemBlockPredicateBlockSetId, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		if ItemBlockPredicateBlockSetId != 0 {
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetId
+		} else {
+			var ItemBlockPredicateBlockSetResult string
+			ItemBlockPredicateBlockSetResult, err = proto_base.DecodeString(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicateBlockSetPresentValue = ItemBlockPredicateBlockSetResult
+		}
+		ret.BlockSet = &ItemBlockPredicateBlockSetPresentValue
+	}
+	var ItemBlockPredicatePropertiesPresent bool
+	err = binary.Read(r, binary.BigEndian, &ItemBlockPredicatePropertiesPresent)
+	if err != nil {
+		return
+	}
+	if ItemBlockPredicatePropertiesPresent {
+		var ItemBlockPredicatePropertiesPresentValue []ItemBlockProperty
+		var lItemBlockPredicateProperties int32
+		lItemBlockPredicateProperties, err = proto_base.DecodeVarInt(r)
+		if err != nil {
+			return
+		}
+		ItemBlockPredicatePropertiesPresentValue = []ItemBlockProperty{}
+		for range lItemBlockPredicateProperties {
+			var ItemBlockPredicatePropertiesElement ItemBlockProperty
+			err = ItemBlockPredicatePropertiesElement.Decode(r)
+			if err != nil {
+				return
+			}
+			ItemBlockPredicatePropertiesPresentValue = append(ItemBlockPredicatePropertiesPresentValue, ItemBlockPredicatePropertiesElement)
+		}
+		ret.Properties = &ItemBlockPredicatePropertiesPresentValue
+	}
+	err = ret.Nbt.Decode(r)
+	if err != nil {
+		return
+	}
+	err = ret.Components.Decode(r)
+	if err != nil {
+		return
+	}
 	return
 }
 func (ret *ItemBlockPredicate) Encode(w io.Writer) (err error) {
-	err = proto_base.ToDoError
+	err = binary.Write(w, binary.BigEndian, ret.BlockSet != nil)
+	if err != nil {
+		return
+	}
+	if ret.BlockSet != nil {
+		switch ItemBlockPredicateBlockSetKnownType := (*ret.BlockSet).(type) {
+		case string:
+			err = proto_base.EncodeVarInt(w, 0)
+			if err != nil {
+				return
+			}
+			err = proto_base.EncodeString(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		case int32:
+			err = proto_base.EncodeVarInt(w, ItemBlockPredicateBlockSetKnownType)
+			if err != nil {
+				return
+			}
+		default:
+			err = proto_base.BadTypeError
+		}
+	}
+	err = binary.Write(w, binary.BigEndian, ret.Properties != nil)
+	if err != nil {
+		return
+	}
+	if ret.Properties != nil {
+		err = proto_base.EncodeVarInt(w, int32(len(*ret.Properties)))
+		if err != nil {
+			return
+		}
+		for iItemBlockPredicateProperties := range len(*ret.Properties) {
+			ItemBlockPredicatePropertiesInnerEncTmp := (*ret.Properties)[iItemBlockPredicateProperties]
+			err = ItemBlockPredicatePropertiesInnerEncTmp.Encode(w)
+			if err != nil {
+				return
+			}
+		}
+	}
+	ItemBlockPredicateNbtEncTmp := ret.Nbt
+	err = ItemBlockPredicateNbtEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
+	ItemBlockPredicateComponentsEncTmp := ret.Components
+	err = ItemBlockPredicateComponentsEncTmp.Encode(w)
+	if err != nil {
+		return
+	}
 	return
 }
 

mc/proto_generator/native_decoder.go

@@ -456,56 +456,38 @@ func RegistryEntryHolderSetDecoder(g *Generator, varToSet ast.Expr, dataRaw any,
 	if err != nil {
 		return
 	}
-	var countType ast.Expr
-	countType, err = g.VisitType("varint")
+	idName := name + "Id"
+	varIntType, err := g.VisitNameAndData("varint", nil)
 	if err != nil {
 		return
 	}
+	IdVar := VarStmt(idName, varIntType)
+	idDecodeStatements, err := g.VisitDecoder(Ident(idName), "varint", name)
+	if err != nil {
+		return
+	}
+
 	baseType, err := g.VisitType(data.Base.Type)
 	if err != nil {
 		return
 	}
-	otherwiseArrayType, err := g.VisitNameAndData("array", map[string]any{"type": data.Otherwise.Type})
+	resName := name + "Result"
+	var basePath []ast.Stmt
+	basePath = append(basePath, VarStmt(resName, baseType))
+	baseDecodeStatements, err := g.VisitDecoder(Ident(resName), data.Base.Type, name+"Base")
 	if err != nil {
 		return
 	}
-	otherwiseType, err := g.VisitType(data.Otherwise.Type)
-	if err != nil {
-		return
-	}
-	lName := "l" + util2.CamelCase(name)
-	s1 := VarStmt(lName, countType)
-	s2, err := g.VisitDecoder(Ident(lName), "varint", name)
-	if err != nil {
-		return
-	}
-	s3 := Assign121(Ident(lName), Sub(Ident(lName), NumLit(1)))
-	resultName := name + "Result"
-	b1s1 := VarStmt(resultName, baseType)
-	b1s2, err := g.VisitDecoder(Ident(resultName), data.Base.Type, resultName)
-	b1s3 := Assign121(varToSet, Ident(resultName))
-	b1s4 := Return()
-	var b1 []ast.Stmt
-	b1 = append(b1, b1s1)
-	b1 = append(b1, b1s2...)
-	b1 = append(b1, b1s3)
-	b1 = append(b1, b1s4)
+	basePath = append(basePath, baseDecodeStatements...)
+	basePath = append(basePath, Assign121(varToSet, Ident(resName)))
 
-	tName := name + "Element"
-	rangeStatements := Stmts(VarStmt(tName, otherwiseType))
-	rangeStatementsDecode, err := g.VisitDecoder(Ident(tName), data.Otherwise.Type, tName)
-	rangeStatements = append(rangeStatements, rangeStatementsDecode...)
-	rangeStatements = append(rangeStatements, Assign121(Ident(resultName), Call(Ident("append"), Ident(resultName), Ident(tName))))
+	idPath := IfElse(NotEquals(Ident(idName), NumLit(0)),
+		NewBlockEllipsis(Assign121(varToSet, Ident(idName))),
+		NewBlock(basePath))
 
-	s5 := If(Equals(Ident(lName), NumLit(-1)), NewBlock(b1))
-	s6 := VarStmt(resultName, otherwiseArrayType)
-	s7 := ForRange(nil, Ident(lName), NewBlock(rangeStatements))
-	s = append(s, s1)
-	s = append(s, s2...)
-	s = append(s, s3)
-	s = append(s, s5)
-	s = append(s, s6)
-	s = append(s, s7)
+	s = Stmts(IdVar)
+	s = append(s, idDecodeStatements...)
+	s = append(s, idPath)
 	return
 }
 
@@ -705,7 +687,7 @@ func (g *Generator) RegisterDecoderNatives() {
 		"bool": SimpleTypeDecoder,
 
 		"registryEntryHolder":      RegistryEntryHolderDecoder,
-		"registryEntryHolderSet":   ToDoDecoder, // RegistryEntryHolderSetDecoder
+		"registryEntryHolderSet":   RegistryEntryHolderSetDecoder,
 		"entityMetadataLoop":       EntityMetadataLoopDecoder,
 		"topBitSetTerminatedArray": TopBitSetTerminatedArrayDecoder,
 		"todo":                     ToDoDecoder,

mc/proto_generator/native_encoder.go

@@ -490,6 +490,49 @@ func TopBitSetTerminatedArrayEncoder(g *Generator, varToSet ast.Expr, dataRaw an
 	return
 }
 
+func RegistryEntryHolderSetEncoder(g *Generator, varToSet ast.Expr, dataRaw any, name string) (s []ast.Stmt, err error) {
+	var data protodef.RegistryEntryHolderSet
+	err = mapstructure.Decode(dataRaw, &data)
+	if err != nil {
+		return
+	}
+
+	baseType, err := g.VisitType(data.Base.Type)
+	if err != nil {
+		return
+	}
+	otherwiseType, err := g.VisitType(data.Otherwise.Type)
+	if err != nil {
+		return
+	}
+
+	knownTypeName := name + "KnownType"
+
+	zeroEncode, err := g.VisitEncoder(NumLit(0), "varint", name+"Zero")
+	if err != nil {
+		return
+	}
+
+	baseEncodeStatements, err := g.VisitEncoder(Ident(knownTypeName), data.Base.Type, name+"Base")
+	if err != nil {
+		return
+	}
+	baseEncodeStatements = append(zeroEncode, baseEncodeStatements...)
+
+	otherwiseEncodeStatements, err := g.VisitEncoder(Ident(knownTypeName), data.Otherwise.Type, name+"Otherwise")
+	if err != nil {
+		return
+	}
+
+	statements := Stmts()
+	statements = append(statements, Case(Exprs(baseType), baseEncodeStatements))
+	statements = append(statements, Case(Exprs(otherwiseType), otherwiseEncodeStatements))
+	statements = append(statements, Case(nil, Stmts(Assign121(Ident("err"), Selector("proto_base", "BadTypeError")))))
+
+	s = Stmts(TypeSwitch(Define121(Ident(knownTypeName), TypeAssert(varToSet, Ident("type"))), NewBlock(statements)))
+	return
+}
+
 func (g *Generator) RegisterEncoderNatives() {
 	g.EncoderNatives = map[string]FunctionGeneratorFunc{
 		"container": ContainerEncoder,
@@ -526,7 +569,7 @@ func (g *Generator) RegisterEncoderNatives() {
 		"bool": SimpleTypeEncoder,
 
 		"registryEntryHolder":      RegistryEntryHolderEncoder,
-		"registryEntryHolderSet":   ToDoEncoder,
+		"registryEntryHolderSet":   RegistryEntryHolderSetEncoder,
 		"entityMetadataLoop":       EntityMetadataLoopEncoder,
 		"topBitSetTerminatedArray": TopBitSetTerminatedArrayEncoder,
 		"todo":                     ToDoEncoder,