Add EmptyStruct operation

encode_compile.go

@@ -238,6 +238,9 @@ func encodeConvertHeadOnlyCode(c *opcode, isPtrHead bool) {
 	if strings.Contains(c.op.String(), "Map") {
 		return
 	}
+	if strings.Contains(c.op.String(), "EmptyStruct") {
+		return
+	}
 
 	isPtrOp := strings.Contains(c.op.String(), "Ptr")
 	if isPtrOp && !isPtrHead {
@@ -628,6 +631,12 @@ func encodeCompileBytes(ctx *encodeCompileContext) (*opcode, error) {
 	return code, nil
 }
 
+func encodeCompileEmptyStruct(ctx *encodeCompileContext) (*opcode, error) {
+	code := newOpCode(ctx, opEmptyStruct)
+	ctx.incIndex()
+	return code, nil
+}
+
 func encodeCompileInterface(ctx *encodeCompileContext) (*opcode, error) {
 	code := newInterfaceCode(ctx)
 	ctx.incIndex()
@@ -814,6 +823,8 @@ func encodeTypeToHeaderType(ctx *encodeCompileContext, code *opcode) opType {
 				return opStructFieldHeadStringPtr
 			case opBool:
 				return opStructFieldHeadBoolPtr
+			case opEmptyStruct:
+				return opStructFieldHeadEmptyStructPtr
 			}
 		}
 	case opInt:
@@ -828,6 +839,8 @@ func encodeTypeToHeaderType(ctx *encodeCompileContext, code *opcode) opType {
 		return opStructFieldHeadString
 	case opBool:
 		return opStructFieldHeadBool
+	case opEmptyStruct:
+		return opStructFieldHeadEmptyStruct
 	case opMapHead:
 		return opStructFieldHeadMap
 	case opMapHeadLoad:
@@ -836,8 +849,6 @@ func encodeTypeToHeaderType(ctx *encodeCompileContext, code *opcode) opType {
 		return opStructFieldHeadArray
 	case opSliceHead:
 		return opStructFieldHeadSlice
-	case opStructFieldHead:
-		return opStructFieldHeadStruct
 	case opMarshalJSON:
 		return opStructFieldHeadMarshalJSON
 	case opMarshalText:
@@ -897,6 +908,8 @@ func encodeTypeToFieldType(ctx *encodeCompileContext, code *opcode) opType {
 				return opStructFieldStringPtr
 			case opBool:
 				return opStructFieldBoolPtr
+			case opEmptyStruct:
+				return opStructFieldEmptyStructPtr
 			}
 		}
 	case opInt:
@@ -911,6 +924,8 @@ func encodeTypeToFieldType(ctx *encodeCompileContext, code *opcode) opType {
 		return opStructFieldString
 	case opBool:
 		return opStructFieldBool
+	case opEmptyStruct:
+		return opStructFieldEmptyStruct
 	case opMapHead:
 		return opStructFieldMap
 	case opMapHeadLoad:
@@ -919,8 +934,6 @@ func encodeTypeToFieldType(ctx *encodeCompileContext, code *opcode) opType {
 		return opStructFieldArray
 	case opSliceHead:
 		return opStructFieldSlice
-	case opStructFieldHead:
-		return opStructFieldStruct
 	case opMarshalJSON:
 		return opStructFieldMarshalJSON
 	case opMarshalText:
@@ -1220,13 +1233,16 @@ func encodeCompileStruct(ctx *encodeCompileContext, isPtr bool) (*opcode, error)
 		return code, nil
 	}
 	typ := ctx.typ
+	fieldNum := typ.NumField()
+	if fieldNum == 0 {
+		return encodeCompileEmptyStruct(ctx)
+	}
 	typeptr := uintptr(unsafe.Pointer(typ))
 	compiled := &compiledCode{}
 	ctx.structTypeToCompiledCode[typeptr] = compiled
 	// header => code => structField => code => end
 	//                        ^          |
 	//                        |__________|
-	fieldNum := typ.NumField()
 	fieldIdx := 0
 	var (
 		head      *opcode

encode_vm.go

@@ -142,6 +142,10 @@ func encodeRun(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, opt Enco
 			}
 			b = encodeComma(b)
 			code = code.next
+		case opEmptyStruct:
+			b = append(b, '{', '}')
+			b = encodeComma(b)
+			code = code.next
 		case opInterface:
 			ptr := load(ctxptr, code.idx)
 			if ptr == 0 {
@@ -3357,6 +3361,64 @@ func encodeRun(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, opt Enco
 				b = encodeComma(b)
 				code = code.next
 			}
+		case opStructFieldPtrHeadEmptyStruct:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeComma(b)
+				code = code.end.next
+				break
+			}
+			store(ctxptr, code.idx, ptrToPtr(p))
+			fallthrough
+		case opStructFieldHeadEmptyStruct:
+			b = append(b, '{')
+			b = append(b, code.key...)
+			b = append(b, '{', '}')
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldPtrHeadEmptyStructPtr:
+			store(ctxptr, code.idx, ptrToPtr(load(ctxptr, code.idx)))
+			fallthrough
+		case opStructFieldHeadEmptyStructPtr:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeComma(b)
+				code = code.end.next
+				break
+			} else {
+				b = append(b, '{')
+				b = append(b, code.key...)
+				p = ptrToPtr(p)
+				if p == 0 {
+					b = encodeNull(b)
+				} else {
+					b = append(b, '{', '}')
+				}
+			}
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldPtrHeadOmitEmptyEmptyStructPtr:
+			store(ctxptr, code.idx, ptrToPtr(load(ctxptr, code.idx)))
+			fallthrough
+		case opStructFieldHeadOmitEmptyEmptyStructPtr:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeComma(b)
+				code = code.end.next
+				break
+			} else {
+				p = ptrToPtr(p)
+				b = append(b, '{')
+				if p != 0 {
+					b = append(b, code.key...)
+					b = append(b, '{', '}')
+				}
+			}
+			b = encodeComma(b)
+			code = code.next
 		case opStructFieldPtrHeadArray:
 			p := load(ctxptr, code.idx)
 			if p == 0 {
@@ -4453,6 +4515,52 @@ func encodeRun(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, opt Enco
 			}
 			b = encodeComma(b)
 			code = code.next
+		case opStructFieldEmptyStruct:
+			b = append(b, code.key...)
+			b = append(b, '{', '}')
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldOmitEmptyEmptyStruct:
+			b = append(b, code.key...)
+			b = append(b, '{', '}')
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldStringTagEmptyStruct:
+			b = append(b, code.key...)
+			b = append(b, `"{}"`...)
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldEmptyStructPtr:
+			b = append(b, code.key...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, '{', '}')
+			}
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldOmitEmptyEmptyStructPtr:
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p != 0 {
+				b = append(b, code.key...)
+				b = append(b, '{', '}')
+				b = encodeComma(b)
+			}
+			code = code.next
+		case opStructFieldStringTagEmptyStructPtr:
+			b = append(b, code.key...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, `"{}"`...)
+			}
+			b = encodeComma(b)
+			code = code.next
 		case opStructFieldMarshalJSON:
 			ptr := load(ctxptr, code.headIdx)
 			b = append(b, code.key...)
@@ -5215,6 +5323,52 @@ func encodeRun(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, opt Enco
 			b = encodeByteSlice(b, v)
 			b = appendStructEnd(b)
 			code = code.next
+		case opStructEndEmptyStruct:
+			b = append(b, code.key...)
+			b = append(b, '{', '}')
+			b = appendStructEnd(b)
+			code = code.next
+		case opStructEndOmitEmptyEmptyStruct:
+			b = append(b, code.key...)
+			b = append(b, '{', '}')
+			b = appendStructEnd(b)
+			code = code.next
+		case opStructEndStringTagEmptyStruct:
+			b = append(b, code.key...)
+			b = append(b, `"{}"`...)
+			b = appendStructEnd(b)
+			code = code.next
+		case opStructEndEmptyStructPtr:
+			b = append(b, code.key...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, '{', '}')
+			}
+			b = appendStructEnd(b)
+			code = code.next
+		case opStructEndOmitEmptyEmptyStructPtr:
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p != 0 {
+				b = append(b, code.key...)
+				b = append(b, '{', '}')
+				b = appendStructEnd(b)
+			}
+			code = code.next
+		case opStructEndStringTagEmptyStructPtr:
+			b = append(b, code.key...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, `"{}"`...)
+			}
+			b = appendStructEnd(b)
+			code = code.next
 		case opStructEndMarshalJSON:
 			ptr := load(ctxptr, code.headIdx)
 			b = append(b, code.key...)

encode_vm_escaped.go

@@ -76,6 +76,10 @@ func encodeRunEscaped(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, o
 			}
 			b = encodeComma(b)
 			code = code.next
+		case opEmptyStruct:
+			b = append(b, '{', '}')
+			b = encodeComma(b)
+			code = code.next
 		case opInterface:
 			ptr := load(ctxptr, code.idx)
 			if ptr == 0 {
@@ -3295,6 +3299,64 @@ func encodeRunEscaped(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, o
 				b = encodeComma(b)
 				code = code.next
 			}
+		case opStructFieldPtrHeadEmptyStruct:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeComma(b)
+				code = code.end.next
+				break
+			}
+			store(ctxptr, code.idx, ptrToPtr(p))
+			fallthrough
+		case opStructFieldHeadEmptyStruct:
+			b = append(b, '{')
+			b = append(b, code.escapedKey...)
+			b = append(b, '{', '}')
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldPtrHeadEmptyStructPtr:
+			store(ctxptr, code.idx, ptrToPtr(load(ctxptr, code.idx)))
+			fallthrough
+		case opStructFieldHeadEmptyStructPtr:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeComma(b)
+				code = code.end.next
+				break
+			} else {
+				b = append(b, '{')
+				b = append(b, code.escapedKey...)
+				p = ptrToPtr(p)
+				if p == 0 {
+					b = encodeNull(b)
+				} else {
+					b = append(b, '{', '}')
+				}
+			}
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldPtrHeadOmitEmptyEmptyStructPtr:
+			store(ctxptr, code.idx, ptrToPtr(load(ctxptr, code.idx)))
+			fallthrough
+		case opStructFieldHeadOmitEmptyEmptyStructPtr:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeComma(b)
+				code = code.end.next
+				break
+			} else {
+				p = ptrToPtr(p)
+				b = append(b, '{')
+				if p != 0 {
+					b = append(b, code.escapedKey...)
+					b = append(b, '{', '}')
+				}
+			}
+			b = encodeComma(b)
+			code = code.next
 		case opStructFieldPtrHeadArray:
 			p := load(ctxptr, code.idx)
 			if p == 0 {
@@ -4387,6 +4449,52 @@ func encodeRunEscaped(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, o
 			}
 			b = encodeComma(b)
 			code = code.next
+		case opStructFieldEmptyStruct:
+			b = append(b, code.escapedKey...)
+			b = append(b, '{', '}')
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldOmitEmptyEmptyStruct:
+			b = append(b, code.escapedKey...)
+			b = append(b, '{', '}')
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldStringTagEmptyStruct:
+			b = append(b, code.escapedKey...)
+			b = append(b, `"{}"`...)
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldEmptyStructPtr:
+			b = append(b, code.escapedKey...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, '{', '}')
+			}
+			b = encodeComma(b)
+			code = code.next
+		case opStructFieldOmitEmptyEmptyStructPtr:
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p != 0 {
+				b = append(b, code.escapedKey...)
+				b = append(b, '{', '}')
+				b = encodeComma(b)
+			}
+			code = code.next
+		case opStructFieldStringTagEmptyStructPtr:
+			b = append(b, code.escapedKey...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, `"{}"`...)
+			}
+			b = encodeComma(b)
+			code = code.next
 		case opStructFieldMarshalJSON:
 			ptr := load(ctxptr, code.headIdx)
 			b = append(b, code.escapedKey...)
@@ -5158,6 +5266,52 @@ func encodeRunEscaped(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, o
 			b = encodeByteSlice(b, v)
 			b = appendStructEnd(b)
 			code = code.next
+		case opStructEndEmptyStruct:
+			b = append(b, code.escapedKey...)
+			b = append(b, '{', '}')
+			b = appendStructEnd(b)
+			code = code.next
+		case opStructEndOmitEmptyEmptyStruct:
+			b = append(b, code.escapedKey...)
+			b = append(b, '{', '}')
+			b = appendStructEnd(b)
+			code = code.next
+		case opStructEndStringTagEmptyStruct:
+			b = append(b, code.escapedKey...)
+			b = append(b, `"{}"`...)
+			b = appendStructEnd(b)
+			code = code.next
+		case opStructEndEmptyStructPtr:
+			b = append(b, code.escapedKey...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, '{', '}')
+			}
+			b = appendStructEnd(b)
+			code = code.next
+		case opStructEndOmitEmptyEmptyStructPtr:
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p != 0 {
+				b = append(b, code.escapedKey...)
+				b = append(b, '{', '}')
+				b = appendStructEnd(b)
+			}
+			code = code.next
+		case opStructEndStringTagEmptyStructPtr:
+			b = append(b, code.escapedKey...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, `"{}"`...)
+			}
+			b = appendStructEnd(b)
+			code = code.next
 		case opStructEndMarshalJSON:
 			ptr := load(ctxptr, code.headIdx)
 			b = append(b, code.escapedKey...)

encode_vm_escaped_indent.go

@@ -75,6 +75,10 @@ func encodeRunEscapedIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcode
 			}
 			b = encodeIndentComma(b)
 			code = code.next
+		case opEmptyStruct:
+			b = append(b, '{', '}')
+			b = encodeIndentComma(b)
+			code = code.next
 		case opInterface:
 			ptr := load(ctxptr, code.idx)
 			if ptr == 0 {
@@ -493,13 +497,11 @@ func encodeRunEscapedIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcode
 		case opStructFieldHead:
 			ptr := load(ctxptr, code.idx)
 			if ptr == 0 {
-				b = appendIndent(ctx, b, code.indent)
 				b = encodeNull(b)
 				b = encodeIndentComma(b)
 				code = code.end.next
 			} else if code.next == code.end {
 				// not exists fields
-				b = appendIndent(ctx, b, code.indent)
 				b = append(b, '{', '}', ',', '\n')
 				code = code.end.next
 				store(ctxptr, code.idx, ptr)
@@ -523,12 +525,10 @@ func encodeRunEscapedIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcode
 		case opStructFieldHeadOmitEmpty:
 			ptr := load(ctxptr, code.idx)
 			if ptr == 0 {
-				b = appendIndent(ctx, b, code.indent)
 				b = encodeNull(b)
 				b = encodeIndentComma(b)
 				code = code.end.next
 			} else {
-				b = appendIndent(ctx, b, code.indent)
 				b = append(b, '{', '\n')
 				p := ptr + code.offset
 				if p == 0 || *(*uintptr)(*(*unsafe.Pointer)(unsafe.Pointer(&p))) == 0 {
@@ -3579,6 +3579,64 @@ func encodeRunEscapedIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcode
 					code = code.next
 				}
 			}
+		case opStructFieldPtrHeadEmptyStruct:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeIndentComma(b)
+				code = code.end.next
+				break
+			}
+			store(ctxptr, code.idx, ptrToPtr(p))
+			fallthrough
+		case opStructFieldHeadEmptyStruct:
+			b = append(b, '{')
+			b = append(b, code.escapedKey...)
+			b = append(b, ' ', '{', '}')
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldPtrHeadEmptyStructPtr:
+			store(ctxptr, code.idx, ptrToPtr(load(ctxptr, code.idx)))
+			fallthrough
+		case opStructFieldHeadEmptyStructPtr:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeIndentComma(b)
+				code = code.end.next
+				break
+			} else {
+				b = append(b, '{')
+				b = append(b, code.escapedKey...)
+				p = ptrToPtr(p)
+				if p == 0 {
+					b = encodeNull(b)
+				} else {
+					b = append(b, '{', '}')
+				}
+			}
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldPtrHeadOmitEmptyEmptyStructPtr:
+			store(ctxptr, code.idx, ptrToPtr(load(ctxptr, code.idx)))
+			fallthrough
+		case opStructFieldHeadOmitEmptyEmptyStructPtr:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeIndentComma(b)
+				code = code.end.next
+				break
+			} else {
+				p = ptrToPtr(p)
+				b = append(b, '{')
+				if p != 0 {
+					b = append(b, code.escapedKey...)
+					b = append(b, ' ', '{', '}')
+				}
+			}
+			b = encodeIndentComma(b)
+			code = code.next
 		case opStructFieldPtrHeadStringTag:
 			ptr := load(ctxptr, code.idx)
 			if ptr != 0 {
@@ -4139,6 +4197,58 @@ func encodeRunEscapedIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcode
 			}
 			b = encodeIndentComma(b)
 			code = code.next
+		case opStructFieldEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			b = append(b, ' ', '{', '}')
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldOmitEmptyEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			b = append(b, ' ', '{', '}')
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldStringTagEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			b = append(b, ` "{}"`...)
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldEmptyStructPtr:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, ' ', '{', '}')
+			}
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldOmitEmptyEmptyStructPtr:
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p != 0 {
+				b = appendIndent(ctx, b, code.indent)
+				b = append(b, code.escapedKey...)
+				b = append(b, ' ', '{', '}')
+				b = encodeIndentComma(b)
+			}
+			code = code.next
+		case opStructFieldStringTagEmptyStructPtr:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, ` "{}"`...)
+			}
+			b = encodeIndentComma(b)
+			code = code.next
 		case opStructFieldMarshalJSON:
 			b = appendIndent(ctx, b, code.indent)
 			b = append(b, code.escapedKey...)
@@ -5023,6 +5133,58 @@ func encodeRunEscapedIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcode
 			b = encodeByteSlice(b, ptrToBytes(ptr+code.offset))
 			b = appendStructEndIndent(ctx, b, code.indent-1)
 			code = code.next
+		case opStructEndEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			b = append(b, ' ', '{', '}')
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
+		case opStructEndOmitEmptyEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			b = append(b, ' ', '{', '}')
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
+		case opStructEndStringTagEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			b = append(b, ` "{}"`...)
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
+		case opStructEndEmptyStructPtr:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, ' ', '{', '}')
+			}
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
+		case opStructEndOmitEmptyEmptyStructPtr:
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p != 0 {
+				b = appendIndent(ctx, b, code.indent)
+				b = append(b, code.escapedKey...)
+				b = append(b, ' ', '{', '}')
+				b = appendStructEndIndent(ctx, b, code.indent-1)
+			}
+			code = code.next
+		case opStructEndStringTagEmptyStructPtr:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.escapedKey...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, ` "{}"`...)
+			}
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
 		case opStructEndMarshalJSON:
 			b = appendIndent(ctx, b, code.indent)
 			b = append(b, code.escapedKey...)

encode_vm_indent.go

@@ -75,6 +75,10 @@ func encodeRunIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, op
 			}
 			b = encodeIndentComma(b)
 			code = code.next
+		case opEmptyStruct:
+			b = append(b, '{', '}')
+			b = encodeIndentComma(b)
+			code = code.next
 		case opInterface:
 			ptr := load(ctxptr, code.idx)
 			if ptr == 0 {
@@ -3579,6 +3583,64 @@ func encodeRunIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, op
 					code = code.next
 				}
 			}
+		case opStructFieldPtrHeadEmptyStruct:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeIndentComma(b)
+				code = code.end.next
+				break
+			}
+			store(ctxptr, code.idx, ptrToPtr(p))
+			fallthrough
+		case opStructFieldHeadEmptyStruct:
+			b = append(b, '{')
+			b = append(b, code.key...)
+			b = append(b, ' ', '{', '}')
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldPtrHeadEmptyStructPtr:
+			store(ctxptr, code.idx, ptrToPtr(load(ctxptr, code.idx)))
+			fallthrough
+		case opStructFieldHeadEmptyStructPtr:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeIndentComma(b)
+				code = code.end.next
+				break
+			} else {
+				b = append(b, '{')
+				b = append(b, code.key...)
+				p = ptrToPtr(p)
+				if p == 0 {
+					b = encodeNull(b)
+				} else {
+					b = append(b, '{', '}')
+				}
+			}
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldPtrHeadOmitEmptyEmptyStructPtr:
+			store(ctxptr, code.idx, ptrToPtr(load(ctxptr, code.idx)))
+			fallthrough
+		case opStructFieldHeadOmitEmptyEmptyStructPtr:
+			p := load(ctxptr, code.idx)
+			if p == 0 {
+				b = encodeNull(b)
+				b = encodeIndentComma(b)
+				code = code.end.next
+				break
+			} else {
+				p = ptrToPtr(p)
+				b = append(b, '{')
+				if p != 0 {
+					b = append(b, code.key...)
+					b = append(b, ' ', '{', '}')
+				}
+			}
+			b = encodeIndentComma(b)
+			code = code.next
 		case opStructFieldPtrHeadStringTag:
 			ptr := load(ctxptr, code.idx)
 			if ptr != 0 {
@@ -4139,6 +4201,58 @@ func encodeRunIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, op
 			}
 			b = encodeIndentComma(b)
 			code = code.next
+		case opStructFieldEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			b = append(b, ' ', '{', '}')
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldOmitEmptyEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			b = append(b, ' ', '{', '}')
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldStringTagEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			b = append(b, ` "{}"`...)
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldEmptyStructPtr:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, ' ', '{', '}')
+			}
+			b = encodeIndentComma(b)
+			code = code.next
+		case opStructFieldOmitEmptyEmptyStructPtr:
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p != 0 {
+				b = appendIndent(ctx, b, code.indent)
+				b = append(b, code.key...)
+				b = append(b, ' ', '{', '}')
+				b = encodeIndentComma(b)
+			}
+			code = code.next
+		case opStructFieldStringTagEmptyStructPtr:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, ` "{}"`...)
+			}
+			b = encodeIndentComma(b)
+			code = code.next
 		case opStructFieldMarshalJSON:
 			b = appendIndent(ctx, b, code.indent)
 			b = append(b, code.key...)
@@ -5022,6 +5136,58 @@ func encodeRunIndent(ctx *encodeRuntimeContext, b []byte, codeSet *opcodeSet, op
 			b = encodeByteSlice(b, ptrToBytes(ptr+code.offset))
 			b = appendStructEndIndent(ctx, b, code.indent-1)
 			code = code.next
+		case opStructEndEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			b = append(b, ' ', '{', '}')
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
+		case opStructEndOmitEmptyEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			b = append(b, ' ', '{', '}')
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
+		case opStructEndStringTagEmptyStruct:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			b = append(b, ` "{}"`...)
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
+		case opStructEndEmptyStructPtr:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, ' ', '{', '}')
+			}
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
+		case opStructEndOmitEmptyEmptyStructPtr:
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p != 0 {
+				b = appendIndent(ctx, b, code.indent)
+				b = append(b, code.key...)
+				b = append(b, ' ', '{', '}')
+				b = appendStructEndIndent(ctx, b, code.indent-1)
+			}
+			code = code.next
+		case opStructEndStringTagEmptyStructPtr:
+			b = appendIndent(ctx, b, code.indent)
+			b = append(b, code.key...)
+			ptr := load(ctxptr, code.headIdx)
+			p := ptrToPtr(ptr + code.offset)
+			if p == 0 {
+				b = encodeNull(b)
+			} else {
+				b = append(b, ` "{}"`...)
+			}
+			b = appendStructEndIndent(ctx, b, code.indent-1)
+			code = code.next
 		case opStructEndMarshalJSON:
 			b = appendIndent(ctx, b, code.indent)
 			b = append(b, code.key...)