Merge pull request #284 from goccy/feature/fix-281

Fix encoding of not empty interface type

encode_test.go

@@ -2108,3 +2108,29 @@ func TestEmbeddedNotFirstField(t *testing.T) {
 		t.Fatalf("failed to encode embedded structure. expected = %q but got %q", expected, got)
 	}
 }
+
+type implementedMethodIface interface {
+	M()
+}
+
+type implementedIfaceType struct {
+	A int
+	B string
+}
+
+func (implementedIfaceType) M() {}
+
+func TestImplementedMethodInterfaceType(t *testing.T) {
+	data := []implementedIfaceType{implementedIfaceType{}}
+	expected, err := stdjson.Marshal(data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got, err := json.Marshal(data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(expected, got) {
+		t.Fatalf("failed to encode implemented method interface type. expected:[%q] but got:[%q]", expected, got)
+	}
+}

internal/cmd/generator/vm.go.tmpl

@@ -7,6 +7,7 @@ import (
 	"unsafe"
 
 	"github.com/goccy/go-json/internal/encoder"
+	"github.com/goccy/go-json/internal/runtime"
 )
 
 func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]byte, error) {
@@ -185,16 +186,28 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 				}
 			}
 			ctx.SeenPtr = append(ctx.SeenPtr, p)
-			iface := (*emptyInterface)(ptrToUnsafePtr(p))
-			if iface.ptr == nil {
+			var (
+				typ      *runtime.Type
+				ifacePtr unsafe.Pointer
+			)
+			up := ptrToUnsafePtr(p)
+			if code.Flags&encoder.NonEmptyInterfaceFlags != 0 {
+				iface := (*nonEmptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.itab.typ
+			} else {
+				iface := (*emptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.typ
+			}
+			if ifacePtr == nil {
 				b = appendNull(ctx, b)
 				b = appendComma(ctx, b)
 				code = code.Next
 				break
 			}
-
-			ctx.KeepRefs = append(ctx.KeepRefs, unsafe.Pointer(iface))
-			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(iface.typ)))
+			ctx.KeepRefs = append(ctx.KeepRefs, up)
+			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(typ)))
 			if err != nil {
 				return nil, err
 			}
@@ -223,7 +236,7 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			ctxptr = ctx.Ptr() + ptrOffset // assign new ctxptr
 
 			end := ifaceCodeSet.EndCode
-			store(ctxptr, c.Idx, uintptr(iface.ptr))
+			store(ctxptr, c.Idx, uintptr(ifacePtr))
 			store(ctxptr, end.Idx, oldOffset)
 			store(ctxptr, end.ElemIdx, uintptr(unsafe.Pointer(code.Next)))
 			storeIndent(ctxptr, end, uintptr(oldBaseIndent))

internal/encoder/opcode.go

@@ -22,6 +22,7 @@ const (
 	IsNextOpPtrTypeFlags   OpFlags = 1 << 6
 	IsNilableTypeFlags     OpFlags = 1 << 7
 	MarshalerContextFlags  OpFlags = 1 << 8
+	NonEmptyInterfaceFlags OpFlags = 1 << 9
 )
 
 type Opcode struct {
@@ -743,6 +744,10 @@ func newMapEndCode(ctx *compileContext, head *Opcode) *Opcode {
 }
 
 func newInterfaceCode(ctx *compileContext) *Opcode {
+	var flag OpFlags
+	if ctx.typ.NumMethod() > 0 {
+		flag |= NonEmptyInterfaceFlags
+	}
 	return &Opcode{
 		Op:         OpInterface,
 		Idx:        opcodeOffset(ctx.ptrIndex),
@@ -750,6 +755,7 @@ func newInterfaceCode(ctx *compileContext) *Opcode {
 		Type:       ctx.typ,
 		DisplayIdx: ctx.opcodeIndex,
 		Indent:     ctx.indent,
+		Flags:      flag,
 	}
 }
 

internal/encoder/vm/util.go

@@ -33,6 +33,15 @@ type emptyInterface struct {
 	ptr unsafe.Pointer
 }
 
+type nonEmptyInterface struct {
+	itab *struct {
+		ityp *runtime.Type // static interface type
+		typ  *runtime.Type // dynamic concrete type
+		// unused fields...
+	}
+	ptr unsafe.Pointer
+}
+
 func errUnimplementedOp(op encoder.OpType) error {
 	return fmt.Errorf("encoder: opcode %s has not been implemented", op)
 }

internal/encoder/vm/vm.go

@@ -7,6 +7,7 @@ import (
 	"unsafe"
 
 	"github.com/goccy/go-json/internal/encoder"
+	"github.com/goccy/go-json/internal/runtime"
 )
 
 func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]byte, error) {
@@ -185,16 +186,28 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 				}
 			}
 			ctx.SeenPtr = append(ctx.SeenPtr, p)
-			iface := (*emptyInterface)(ptrToUnsafePtr(p))
-			if iface.ptr == nil {
+			var (
+				typ      *runtime.Type
+				ifacePtr unsafe.Pointer
+			)
+			up := ptrToUnsafePtr(p)
+			if code.Flags&encoder.NonEmptyInterfaceFlags != 0 {
+				iface := (*nonEmptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.itab.typ
+			} else {
+				iface := (*emptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.typ
+			}
+			if ifacePtr == nil {
 				b = appendNull(ctx, b)
 				b = appendComma(ctx, b)
 				code = code.Next
 				break
 			}
-
-			ctx.KeepRefs = append(ctx.KeepRefs, unsafe.Pointer(iface))
-			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(iface.typ)))
+			ctx.KeepRefs = append(ctx.KeepRefs, up)
+			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(typ)))
 			if err != nil {
 				return nil, err
 			}
@@ -223,7 +236,7 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			ctxptr = ctx.Ptr() + ptrOffset // assign new ctxptr
 
 			end := ifaceCodeSet.EndCode
-			store(ctxptr, c.Idx, uintptr(iface.ptr))
+			store(ctxptr, c.Idx, uintptr(ifacePtr))
 			store(ctxptr, end.Idx, oldOffset)
 			store(ctxptr, end.ElemIdx, uintptr(unsafe.Pointer(code.Next)))
 			storeIndent(ctxptr, end, uintptr(oldBaseIndent))

internal/encoder/vm_color/util.go

@@ -26,6 +26,15 @@ type emptyInterface struct {
 	ptr unsafe.Pointer
 }
 
+type nonEmptyInterface struct {
+	itab *struct {
+		ityp *runtime.Type // static interface type
+		typ  *runtime.Type // dynamic concrete type
+		// unused fields...
+	}
+	ptr unsafe.Pointer
+}
+
 func errUnimplementedOp(op encoder.OpType) error {
 	return fmt.Errorf("encoder: opcode %s has not been implemented", op)
 }

internal/encoder/vm_color/vm.go

@@ -7,6 +7,7 @@ import (
 	"unsafe"
 
 	"github.com/goccy/go-json/internal/encoder"
+	"github.com/goccy/go-json/internal/runtime"
 )
 
 func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]byte, error) {
@@ -185,16 +186,28 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 				}
 			}
 			ctx.SeenPtr = append(ctx.SeenPtr, p)
-			iface := (*emptyInterface)(ptrToUnsafePtr(p))
-			if iface.ptr == nil {
+			var (
+				typ      *runtime.Type
+				ifacePtr unsafe.Pointer
+			)
+			up := ptrToUnsafePtr(p)
+			if code.Flags&encoder.NonEmptyInterfaceFlags != 0 {
+				iface := (*nonEmptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.itab.typ
+			} else {
+				iface := (*emptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.typ
+			}
+			if ifacePtr == nil {
 				b = appendNull(ctx, b)
 				b = appendComma(ctx, b)
 				code = code.Next
 				break
 			}
-
-			ctx.KeepRefs = append(ctx.KeepRefs, unsafe.Pointer(iface))
-			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(iface.typ)))
+			ctx.KeepRefs = append(ctx.KeepRefs, up)
+			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(typ)))
 			if err != nil {
 				return nil, err
 			}
@@ -223,7 +236,7 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			ctxptr = ctx.Ptr() + ptrOffset // assign new ctxptr
 
 			end := ifaceCodeSet.EndCode
-			store(ctxptr, c.Idx, uintptr(iface.ptr))
+			store(ctxptr, c.Idx, uintptr(ifacePtr))
 			store(ctxptr, end.Idx, oldOffset)
 			store(ctxptr, end.ElemIdx, uintptr(unsafe.Pointer(code.Next)))
 			storeIndent(ctxptr, end, uintptr(oldBaseIndent))

internal/encoder/vm_color_indent/util.go

@@ -28,6 +28,15 @@ type emptyInterface struct {
 	ptr unsafe.Pointer
 }
 
+type nonEmptyInterface struct {
+	itab *struct {
+		ityp *runtime.Type // static interface type
+		typ  *runtime.Type // dynamic concrete type
+		// unused fields...
+	}
+	ptr unsafe.Pointer
+}
+
 func errUnimplementedOp(op encoder.OpType) error {
 	return fmt.Errorf("encoder (indent): opcode %s has not been implemented", op)
 }

internal/encoder/vm_color_indent/vm.go

@@ -7,6 +7,7 @@ import (
 	"unsafe"
 
 	"github.com/goccy/go-json/internal/encoder"
+	"github.com/goccy/go-json/internal/runtime"
 )
 
 func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]byte, error) {
@@ -185,16 +186,28 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 				}
 			}
 			ctx.SeenPtr = append(ctx.SeenPtr, p)
-			iface := (*emptyInterface)(ptrToUnsafePtr(p))
-			if iface.ptr == nil {
+			var (
+				typ      *runtime.Type
+				ifacePtr unsafe.Pointer
+			)
+			up := ptrToUnsafePtr(p)
+			if code.Flags&encoder.NonEmptyInterfaceFlags != 0 {
+				iface := (*nonEmptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.itab.typ
+			} else {
+				iface := (*emptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.typ
+			}
+			if ifacePtr == nil {
 				b = appendNull(ctx, b)
 				b = appendComma(ctx, b)
 				code = code.Next
 				break
 			}
-
-			ctx.KeepRefs = append(ctx.KeepRefs, unsafe.Pointer(iface))
-			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(iface.typ)))
+			ctx.KeepRefs = append(ctx.KeepRefs, up)
+			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(typ)))
 			if err != nil {
 				return nil, err
 			}
@@ -223,7 +236,7 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			ctxptr = ctx.Ptr() + ptrOffset // assign new ctxptr
 
 			end := ifaceCodeSet.EndCode
-			store(ctxptr, c.Idx, uintptr(iface.ptr))
+			store(ctxptr, c.Idx, uintptr(ifacePtr))
 			store(ctxptr, end.Idx, oldOffset)
 			store(ctxptr, end.ElemIdx, uintptr(unsafe.Pointer(code.Next)))
 			storeIndent(ctxptr, end, uintptr(oldBaseIndent))

internal/encoder/vm_indent/util.go

@@ -35,6 +35,15 @@ type emptyInterface struct {
 	ptr unsafe.Pointer
 }
 
+type nonEmptyInterface struct {
+	itab *struct {
+		ityp *runtime.Type // static interface type
+		typ  *runtime.Type // dynamic concrete type
+		// unused fields...
+	}
+	ptr unsafe.Pointer
+}
+
 func errUnimplementedOp(op encoder.OpType) error {
 	return fmt.Errorf("encoder (indent): opcode %s has not been implemented", op)
 }

internal/encoder/vm_indent/vm.go

@@ -7,6 +7,7 @@ import (
 	"unsafe"
 
 	"github.com/goccy/go-json/internal/encoder"
+	"github.com/goccy/go-json/internal/runtime"
 )
 
 func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]byte, error) {
@@ -185,16 +186,28 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 				}
 			}
 			ctx.SeenPtr = append(ctx.SeenPtr, p)
-			iface := (*emptyInterface)(ptrToUnsafePtr(p))
-			if iface.ptr == nil {
+			var (
+				typ      *runtime.Type
+				ifacePtr unsafe.Pointer
+			)
+			up := ptrToUnsafePtr(p)
+			if code.Flags&encoder.NonEmptyInterfaceFlags != 0 {
+				iface := (*nonEmptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.itab.typ
+			} else {
+				iface := (*emptyInterface)(up)
+				ifacePtr = iface.ptr
+				typ = iface.typ
+			}
+			if ifacePtr == nil {
 				b = appendNull(ctx, b)
 				b = appendComma(ctx, b)
 				code = code.Next
 				break
 			}
-
-			ctx.KeepRefs = append(ctx.KeepRefs, unsafe.Pointer(iface))
-			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(iface.typ)))
+			ctx.KeepRefs = append(ctx.KeepRefs, up)
+			ifaceCodeSet, err := encoder.CompileToGetCodeSet(uintptr(unsafe.Pointer(typ)))
 			if err != nil {
 				return nil, err
 			}
@@ -223,7 +236,7 @@ func Run(ctx *encoder.RuntimeContext, b []byte, codeSet *encoder.OpcodeSet) ([]b
 			ctxptr = ctx.Ptr() + ptrOffset // assign new ctxptr
 
 			end := ifaceCodeSet.EndCode
-			store(ctxptr, c.Idx, uintptr(iface.ptr))
+			store(ctxptr, c.Idx, uintptr(ifacePtr))
 			store(ctxptr, end.Idx, oldOffset)
 			store(ctxptr, end.ElemIdx, uintptr(unsafe.Pointer(code.Next)))
 			storeIndent(ctxptr, end, uintptr(oldBaseIndent))