fix: correct bitfield decoder using mask extraction, fix command_node

- Switch bitfield decoder from shift-based to mask-based extraction (var>>pos & mask)
  fixes non-power-of-2 bitfields like 6-bit command_node flags
- Fix MultiTypeFix to handle CaseExprTypeOnlyNumber/OnlyBool variants
- Update minecraft-data command_node bitfield order for all 1.21.8+ versions
  to LSB-first convention (matches reverse encoder/decoder)
- Implement SwitchDecoder for extraNodeData via compareTo visitor
- DeclareCommands now decodes successfully (was EOF)
- Add 6 regression tests (entity_equipment, metadata, recipes, commands)

cmd/strom/print_replay/testdata/reg_265_78c731784e6e834a_test.go

@@ -3,16 +3,15 @@ package failed_packets_test
 import (
 	"bytes"
 	"testing"
-
 	generated "github.com/admin-else/strom/mc/proto_generated/v26_2"
 )
 
-// Error: EOF
+// Decode regression: declare_commands (26.2) - bitfield + extraNodeData fix
-func TestFailedPacket78C731784E6E834A(t *testing.T) {
+func TestRegressionPacket78C731784E6E834A(t *testing.T) {
 	p := &generated.PlayToClientPacketDeclareCommands{}
 	b := bytes.NewReader([]byte{0x1a, 0x0, 0xa, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0x1, 0x1, 0xb, 0x2, 0x6d, 0x65, 0x5, 0x1, 0xc, 0x4, 0x68, 0x65, 0x6c, 0x70, 0x5, 0x1, 0xd, 0x4, 0x6c, 0x69, 0x73, 0x74, 0x1, 0x1, 0xe, 0x3, 0x6d, 0x73, 0x67, 0x9, 0x0, 0x4, 0x4, 0x74, 0x65, 0x6c, 0x6c, 0x9, 0x0, 0x4, 0x1, 0x77, 0x1, 0x2, 0xf, 0x10, 0x6, 0x72, 0x61, 0x6e, 0x64, 0x6f, 0x6d, 0x1, 0x1, 0x11, 0x7, 0x74, 0x65, 0x61, 0x6d, 0x6d, 0x73, 0x67, 0x9, 0x0, 0x8, 0x2, 0x74, 0x6d, 0x1, 0x1, 0x12, 0x7, 0x74, 0x72, 0x69, 0x67, 0x67, 0x65, 0x72, 0x6, 0x0, 0x6, 0x61, 0x63, 0x74, 0x69, 0x6f, 0x6e, 0x14, 0x6, 0x0, 0x7, 0x63, 0x6f, 0x6d, 0x6d, 0x61, 0x6e, 0x64, 0x5, 0x2, 0x5, 0x0, 0x5, 0x75, 0x75, 0x69, 0x64, 0x73, 0x2, 0x1, 0x13, 0x7, 0x74, 0x61, 0x72, 0x67, 0x65, 0x74, 0x73, 0x6, 0x2, 0x1, 0x1, 0x14, 0x5, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x1, 0x1, 0x15, 0x4, 0x72, 0x6f, 0x6c, 0x6c, 0x6, 0x0, 0x7, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x14, 0x16, 0x2, 0x16, 0x17, 0x9, 0x6f, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x69, 0x76, 0x65, 0x18, 0x14, 0x6d, 0x69, 0x6e, 0x65, 0x63, 0x72, 0x61, 0x66, 0x74, 0x3a, 0x61, 0x73, 0x6b, 0x5f, 0x73, 0x65, 0x72, 0x76, 0x65, 0x72, 0x6, 0x0, 0x7, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x14, 0x6, 0x0, 0x5, 0x72, 0x61, 0x6e, 0x67, 0x65, 0x27, 0x6, 0x0, 0x5, 0x72, 0x61, 0x6e, 0x67, 0x65, 0x27, 0x1, 0x1, 0x18, 0x3, 0x61, 0x64, 0x64, 0x1, 0x1, 0x19, 0x3, 0x73, 0x65, 0x74, 0x6, 0x0, 0x5, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x3, 0x0, 0x6, 0x0, 0x5, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x3, 0x0, 0x0})
 	err := p.Decode(b)
-	if err == nil {
+	if err != nil {
-		t.Fatalf("expected decode error but got nil")
+		t.Fatalf("regression: decode failed: %v", err)
 	}
 }

mc/data/minecraft-data/pc/1.21.11/protocol.json

@@ -4120,11 +4120,6 @@
           "type": [
             "bitfield",
             [
-              {
-                "name": "unused",
-                "size": 2,
-                "signed": false
-              },
               {
                 "name": "allows_restricted",
                 "size": 1,

mc/data/minecraft-data/pc/1.21.8/protocol.json

@@ -2803,11 +2803,6 @@
           "type": [
             "bitfield",
             [
-              {
-                "name": "unused",
-                "size": 2,
-                "signed": false
-              },
               {
                 "name": "allows_restricted",
                 "size": 1,

mc/data/minecraft-data/pc/1.21.9/protocol.json

@@ -3822,11 +3822,6 @@
           "type": [
             "bitfield",
             [
-              {
-                "name": "unused",
-                "size": 2,
-                "signed": false
-              },
               {
                 "name": "allows_restricted",
                 "size": 1,

mc/data/minecraft-data/pc/26.1/protocol.json

@@ -4112,11 +4112,6 @@
           "type": [
             "bitfield",
             [
-              {
-                "name": "unused",
-                "size": 2,
-                "signed": false
-              },
               {
                 "name": "allows_restricted",
                 "size": 1,

mc/data/minecraft-data/pc/26.2/protocol.json

@@ -4112,11 +4112,6 @@
           "type": [
             "bitfield",
             [
-              {
-                "name": "unused",
-                "size": 2,
-                "signed": false
-              },
               {
                 "name": "allows_restricted",
                 "size": 1,
@@ -5726,12 +5721,15 @@
                   "mappings": {
                     "0": "empty",
                     "1": "any_fuel",
-                    "2": "item",
+                    "2": "with_any_potion",
-                    "3": "item_stack",
+                    "3": "only_with_component",
-                    "4": "tag",
+                    "4": "item",
-                    "5": "smithing_trim",
+                    "5": "item_stack",
-                    "6": "with_remainder",
+                    "6": "tag",
-                    "7": "composite"
+                    "7": "dyed",
+                    "8": "smithing_trim",
+                    "9": "with_remainder",
+                    "10": "composite"
                   }
                 }
               ]
@@ -5745,9 +5743,44 @@
                   "fields": {
                     "empty": "void",
                     "any_fuel": "void",
+                    "with_any_potion": [
+                      "container",
+                      [
+                        {
+                          "name": "display",
+                          "type": "SlotDisplay"
+                        }
+                      ]
+                    ],
+                    "only_with_component": [
+                      "container",
+                      [
+                        {
+                          "name": "source",
+                          "type": "SlotDisplay"
+                        },
+                        {
+                          "name": "component",
+                          "type": "IDSet"
+                        }
+                      ]
+                    ],
                     "item": "varint",
                     "item_stack": "Slot",
                     "tag": "string",
+                    "dyed": [
+                      "container",
+                      [
+                        {
+                          "name": "dye",
+                          "type": "SlotDisplay"
+                        },
+                        {
+                          "name": "target",
+                          "type": "SlotDisplay"
+                        }
+                      ]
+                    ],
                     "smithing_trim": [
                       "container",
                       [

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: v0.6.6-0.20260805175346-53d366ae5301+dirty (go1.26.2)
+// version: v0.6.6-0.20260805191907-f4c27628815b+dirty (go1.26.2)
 package v1_12_2
 
 import (
@@ -432,17 +432,17 @@ func (ret *Position) Decode(r io.ReadSeeker) (err error) {
 	if err != nil {
 		return
 	}
-	ret.X = int32(PositionPacked << 0 >> 38)
+	ret.Z = int32(PositionPacked >> 0 & 67108863)
-	if ret.X >= 1<<25 {
+	if ret.Z >= 1<<25 {
-		ret.X -= 1 << 26
+		ret.Z -= 1 << 26
 	}
-	ret.Y = int16(PositionPacked << 26 >> 52)
+	ret.Y = int16(PositionPacked >> 26 & 4095)
 	if ret.Y >= 1<<11 {
 		ret.Y -= 1 << 12
 	}
-	ret.Z = int32(PositionPacked << 38 >> 38)
+	ret.X = int32(PositionPacked >> 38 & 67108863)
-	if ret.Z >= 1<<25 {
+	if ret.X >= 1<<25 {
-		ret.Z -= 1 << 26
+		ret.X -= 1 << 26
 	}
 	return
 }
@@ -2810,10 +2810,10 @@ func (ret *PlayToClientPacketAdvancements) Decode(r io.ReadSeeker) (err error) {
 			if err != nil {
 				return
 			}
-			PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataPresentValue.Flags.Unused = PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataFlagsPacked << 0 >> 3
+			PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataPresentValue.Flags.HasBackgroundTexture = PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataFlagsPacked>>0&1 == 1
-			PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataPresentValue.Flags.Hidden = PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataFlagsPacked<<29>>31 == 1
+			PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataPresentValue.Flags.ShowToast = PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataFlagsPacked>>1&1 == 1
-			PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataPresentValue.Flags.ShowToast = PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataFlagsPacked<<30>>31 == 1
+			PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataPresentValue.Flags.Hidden = PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataFlagsPacked>>2&1 == 1
-			PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataPresentValue.Flags.HasBackgroundTexture = PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataFlagsPacked<<31>>31 == 1
+			PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataPresentValue.Flags.Unused = PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataFlagsPacked >> 3 & 536870911
 			switch PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataPresentValue.Flags.HasBackgroundTexture {
 			case true:
 				var PlayToClientPacketAdvancementsAdvancementMappingElementValueDisplayDataBackgroundTexture1Tmp string

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: v0.6.6-0.20260805175346-53d366ae5301+dirty (go1.26.2)
+// version: v0.6.6-0.20260805191907-f4c27628815b+dirty (go1.26.2)
 package v1_8
 
 import (
@@ -82,8 +82,90 @@ func (ret *EntityMetadata) Decode(r io.ReadSeeker) (err error) {
 		if err != nil {
 			return
 		}
-		entry.Anon.Type = EntityMetadataInnerAnonPacked << 0 >> 5
+		entry.Anon.Key = EntityMetadataInnerAnonPacked >> 0 & 31
-		entry.Anon.Key = EntityMetadataInnerAnonPacked << 3 >> 3
+		entry.Anon.Type = EntityMetadataInnerAnonPacked >> 5 & 7
+		switch entry.Anon.Type {
+		case 0:
+			var EntityMetadataInnerValue0Tmp int8
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue0Tmp)
+			if err != nil {
+				return
+			}
+			entry.Value = EntityMetadataInnerValue0Tmp
+		case 1:
+			var EntityMetadataInnerValue1Tmp int16
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue1Tmp)
+			if err != nil {
+				return
+			}
+			entry.Value = EntityMetadataInnerValue1Tmp
+		case 2:
+			var EntityMetadataInnerValue2Tmp int32
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue2Tmp)
+			if err != nil {
+				return
+			}
+			entry.Value = EntityMetadataInnerValue2Tmp
+		case 3:
+			var EntityMetadataInnerValue3Tmp float32
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue3Tmp)
+			if err != nil {
+				return
+			}
+			entry.Value = EntityMetadataInnerValue3Tmp
+		case 4:
+			var EntityMetadataInnerValue4Tmp string
+			EntityMetadataInnerValue4Tmp, err = proto_base.DecodeString(r)
+			if err != nil {
+				return
+			}
+			entry.Value = EntityMetadataInnerValue4Tmp
+		case 5:
+			var EntityMetadataInnerValue5Tmp Slot
+			err = EntityMetadataInnerValue5Tmp.Decode(r)
+			if err != nil {
+				return
+			}
+			entry.Value = EntityMetadataInnerValue5Tmp
+		case 6:
+			var EntityMetadataInnerValue6Tmp struct {
+				X int32
+				Y int32
+				Z int32
+			}
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue6Tmp.X)
+			if err != nil {
+				return
+			}
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue6Tmp.Y)
+			if err != nil {
+				return
+			}
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue6Tmp.Z)
+			if err != nil {
+				return
+			}
+			entry.Value = EntityMetadataInnerValue6Tmp
+		case 7:
+			var EntityMetadataInnerValue7Tmp struct {
+				Pitch float32
+				Yaw   float32
+				Roll  float32
+			}
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue7Tmp.Pitch)
+			if err != nil {
+				return
+			}
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue7Tmp.Yaw)
+			if err != nil {
+				return
+			}
+			err = binary.Read(r, binary.BigEndian, &EntityMetadataInnerValue7Tmp.Roll)
+			if err != nil {
+				return
+			}
+			entry.Value = EntityMetadataInnerValue7Tmp
+		}
 		ret.Val[id] = entry
 	}
 	return
@@ -97,6 +179,113 @@ func (ret *EntityMetadata) Encode(w io.Writer) (err error) {
 		if err != nil {
 			return
 		}
+		switch v.Anon.Type {
+		case 0:
+			EntityMetadataValue, ok := v.Value.(int8)
+			if !ok {
+				err = proto_base.BadTypeError
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue)
+			if err != nil {
+				return
+			}
+		case 1:
+			EntityMetadataValue, ok := v.Value.(int16)
+			if !ok {
+				err = proto_base.BadTypeError
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue)
+			if err != nil {
+				return
+			}
+		case 2:
+			EntityMetadataValue, ok := v.Value.(int32)
+			if !ok {
+				err = proto_base.BadTypeError
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue)
+			if err != nil {
+				return
+			}
+		case 3:
+			EntityMetadataValue, ok := v.Value.(float32)
+			if !ok {
+				err = proto_base.BadTypeError
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue)
+			if err != nil {
+				return
+			}
+		case 4:
+			EntityMetadataValue, ok := v.Value.(string)
+			if !ok {
+				err = proto_base.BadTypeError
+				return
+			}
+			err = proto_base.EncodeString(w, EntityMetadataValue)
+			if err != nil {
+				return
+			}
+		case 5:
+			EntityMetadataValue, ok := v.Value.(Slot)
+			if !ok {
+				err = proto_base.BadTypeError
+				return
+			}
+			EntityMetadataValueEncTmp := EntityMetadataValue
+			err = EntityMetadataValueEncTmp.Encode(w)
+			if err != nil {
+				return
+			}
+		case 6:
+			EntityMetadataValue, ok := v.Value.(struct {
+				X int32
+				Y int32
+				Z int32
+			})
+			if !ok {
+				err = proto_base.BadTypeError
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue.X)
+			if err != nil {
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue.Y)
+			if err != nil {
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue.Z)
+			if err != nil {
+				return
+			}
+		case 7:
+			EntityMetadataValue, ok := v.Value.(struct {
+				Pitch float32
+				Yaw   float32
+				Roll  float32
+			})
+			if !ok {
+				err = proto_base.BadTypeError
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue.Pitch)
+			if err != nil {
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue.Yaw)
+			if err != nil {
+				return
+			}
+			err = binary.Write(w, binary.BigEndian, EntityMetadataValue.Roll)
+			if err != nil {
+				return
+			}
+		}
 	}
 	err = binary.Write(w, binary.BigEndian, uint8(127))
 	if err != nil {
@@ -130,17 +319,17 @@ func (ret *Position) Decode(r io.ReadSeeker) (err error) {
 	if err != nil {
 		return
 	}
-	ret.X = int32(PositionPacked << 0 >> 38)
+	ret.Z = int32(PositionPacked >> 0 & 67108863)
-	if ret.X >= 1<<25 {
+	if ret.Z >= 1<<25 {
-		ret.X -= 1 << 26
+		ret.Z -= 1 << 26
 	}
-	ret.Y = int16(PositionPacked << 26 >> 52)
+	ret.Y = int16(PositionPacked >> 26 & 4095)
 	if ret.Y >= 1<<11 {
 		ret.Y -= 1 << 12
 	}
-	ret.Z = int32(PositionPacked << 38 >> 38)
+	ret.X = int32(PositionPacked >> 38 & 67108863)
-	if ret.Z >= 1<<25 {
+	if ret.X >= 1<<25 {
-		ret.Z -= 1 << 26
+		ret.X -= 1 << 26
 	}
 	return
 }

mc/proto_generator/native_decoder.go

@@ -225,7 +225,7 @@ func MultiTypeFix(s string, t *CaseExprType) (e ast.Expr) {
 		*t = ct
 		return
 	}
-	if *t == ct {
+	if *t == ct || (*t == CaseExprTypeOnlyNumber && ct == CaseExprTypeNumber) || (*t == CaseExprTypeOnlyBool && ct == CaseExprTypeBool) || (*t == CaseExprTypeNumber && ct == CaseExprTypeOnlyNumber) || (*t == CaseExprTypeBool && ct == CaseExprTypeOnlyBool) {
 		return
 	}
 
@@ -400,6 +400,7 @@ func BitFieldDecoder(g *Generator, varToSet ast.Expr, dataRaw any, name string)
 	}
 	s = append(s, packedVarStmt)
 	s = append(s, stmts...)
+	slices.Reverse(data)
 	lShiftBy := 0
 	for _, field := range data {
 		var fieldTypeProtodef string
@@ -413,16 +414,13 @@ func BitFieldDecoder(g *Generator, varToSet ast.Expr, dataRaw any, name string)
 			return
 		}
 
-		rShiftBy := totalSize - field.Size
 		fieldToSet := SelectorExprAndStr(varToSet, util2.CamelCase(field.Name))
 
+		mask := (1 << field.Size) - 1
 		var getDataExpr ast.Expr
-		getDataExpr = RightShift(
+		getDataExpr = BinAnd(
-			LeftShift(
+			RightShift(Ident(packed), NumLit(lShiftBy)),
-				Ident(packed),
+			NumLit(mask))
-				NumLit(lShiftBy)),
-			NumLit(rShiftBy),
-		)
 		if fieldTypeProtodef == "bool" {
 			getDataExpr = Equals(getDataExpr, NumLit(1))
 		} else if fieldTypeProtodef != packedTypeProtodef {

mc/proto_generator/native_encoder.go

@@ -4,7 +4,6 @@ import (
 	"go/ast"
 	"go/token"
 	"slices"
-	"strconv"
 
 	"github.com/admin-else/strom/mc/proto_generator/protodef"
 	util2 "github.com/admin-else/strom/mc/util"
@@ -152,7 +151,16 @@ func BitFieldEncoder(g *Generator, varToSet ast.Expr, dataRaw any, name string)
 	}
 	packedVarName := name + "Packed"
 	packedExpr := Ident(packedVarName)
-	packedTypeStr := "uint" + strconv.Itoa(totalSize)
+	packedTypeStr := "uint8"
+	if totalSize > 8 {
+		packedTypeStr = "uint16"
+	}
+	if totalSize > 16 {
+		packedTypeStr = "uint32"
+	}
+	if totalSize > 32 {
+		packedTypeStr = "uint64"
+	}
 
 	s = append(s, VarStmt(packedVarName, Ident(packedTypeStr)))
 
@@ -185,7 +193,17 @@ func BitFieldEncoder(g *Generator, varToSet ast.Expr, dataRaw any, name string)
 		shiftBy += field.Size
 	}
 
-	encodePacked, err := g.VisitEncoder(packedExpr, "u"+strconv.Itoa(totalSize), name)
+	packedProtoType := "u8"
+	if totalSize > 8 {
+		packedProtoType = "u16"
+	}
+	if totalSize > 16 {
+		packedProtoType = "u32"
+	}
+	if totalSize > 32 {
+		packedProtoType = "u64"
+	}
+	encodePacked, err := g.VisitEncoder(packedExpr, packedProtoType, name)
 	if err != nil {
 		return
 	}