Add Compact/Indent/HTMLEscape/Valid

README.md

@@ -83,27 +83,7 @@ Currently supported all types
 
 ## API
 
-- [ ] `Compact`
+Implements All APIs
-- [ ] `HTMLEscape`
-- [ ] `Indent`
-- [x] `Marshal`
-- [x] `MarshalIndent`
-- [x] `Unmarshal`
-- [ ] `Valid`
-- [x] `NewDecoder`
-- [x] `(*Decoder).Buffered`
-- [x] `(*Decoder).Decode`
-- [x] `(*Decoder).DisallowUnknownFields`
-- [x] `(*Decoder).InputOffset`
-- [x] `(*Decoder).More`
-- [x] `(*Decoder).Token`
-- [x] `(*Decoder).UseNumber`
-- [x] `Delim`
-- [x] `(Delim).String`
-- [x] `NewEncoder`
-- [x] `(*Encoder).Encode`
-- [x] `(*Encoder).SetEscapeHTML`
-- [x] `(*Encoder).SetIndent`
 
 ### Error
 

decode_float.go

@@ -27,6 +27,7 @@ var floatTable = [256]bool{
 	'.': true,
 	'e': true,
 	'E': true,
+	'+': true,
 }
 
 func floatBytes(s *stream) []byte {
@@ -79,8 +80,7 @@ func (d *floatDecoder) decodeByte(buf []byte, cursor int64) ([]byte, int64, erro
 			start := cursor
 			cursor++
 			for ; cursor < buflen; cursor++ {
-				tk := int(buf[cursor])
+				if floatTable[buf[cursor]] {
-				if (int('0') <= tk && tk <= int('9')) || tk == '.' || tk == 'e' || tk == 'E' {
 					continue
 				}
 				break

decode_map.go

@@ -65,7 +65,13 @@ func (d *mapDecoder) decodeStream(s *stream, p uintptr) error {
 	default:
 		return errExpected("{ character for map value", s.totalOffset())
 	}
+	s.skipWhiteSpace()
 	mapValue := makemap(d.mapType, 0)
+	if s.buf[s.cursor+1] == '}' {
+		*(*unsafe.Pointer)(unsafe.Pointer(p)) = mapValue
+		s.cursor++
+		return nil
+	}
 	for {
 		s.cursor++
 		var key interface{}
@@ -131,7 +137,13 @@ func (d *mapDecoder) decode(buf []byte, cursor int64, p uintptr) (int64, error)
 		return 0, errExpected("{ character for map value", cursor)
 	}
 	cursor++
+	cursor = skipWhiteSpace(buf, cursor)
 	mapValue := makemap(d.mapType, 0)
+	if buf[cursor] == '}' {
+		*(*unsafe.Pointer)(unsafe.Pointer(p)) = mapValue
+		cursor++
+		return cursor, nil
+	}
 	for ; cursor < buflen; cursor++ {
 		var key interface{}
 		keyCursor, err := d.setKey(buf, cursor, &key)

decode_slice.go

@@ -72,12 +72,22 @@ func (d *sliceDecoder) decodeStream(s *stream, p uintptr) error {
 			}
 			return nil
 		case '[':
+			s.cursor++
+			s.skipWhiteSpace()
+			if s.char() == ']' {
+				*(*reflect.SliceHeader)(unsafe.Pointer(p)) = reflect.SliceHeader{
+					Data: uintptr(newArray(d.elemType, 0)),
+					Len:  0,
+					Cap:  0,
+				}
+				s.cursor++
+				return nil
+			}
 			idx := 0
 			slice := d.newSlice()
 			cap := slice.cap
 			data := slice.data
 			for {
-				s.cursor++
 				if cap <= idx {
 					src := reflect.SliceHeader{Data: uintptr(data), Len: idx, Cap: cap}
 					cap *= 2
@@ -112,7 +122,6 @@ func (d *sliceDecoder) decodeStream(s *stream, p uintptr) error {
 					return nil
 				case ',':
 					idx++
-					continue
 				case nul:
 					if s.read() {
 						goto RETRY
@@ -127,6 +136,7 @@ func (d *sliceDecoder) decodeStream(s *stream, p uintptr) error {
 					d.releaseSlice(slice)
 					goto ERROR
 				}
+				s.cursor++
 			}
 		case nul:
 			if s.read() {
@@ -162,12 +172,22 @@ func (d *sliceDecoder) decode(buf []byte, cursor int64, p uintptr) (int64, error
 			cursor += 4
 			return cursor, nil
 		case '[':
+			cursor++
+			cursor = skipWhiteSpace(buf, cursor)
+			if buf[cursor] == ']' {
+				*(*reflect.SliceHeader)(unsafe.Pointer(p)) = reflect.SliceHeader{
+					Data: uintptr(newArray(d.elemType, 0)),
+					Len:  0,
+					Cap:  0,
+				}
+				cursor++
+				return cursor, nil
+			}
 			idx := 0
 			slice := d.newSlice()
 			cap := slice.cap
 			data := slice.data
 			for {
-				cursor++
 				if cap <= idx {
 					src := reflect.SliceHeader{Data: uintptr(data), Len: idx, Cap: cap}
 					cap *= 2
@@ -203,13 +223,13 @@ func (d *sliceDecoder) decode(buf []byte, cursor int64, p uintptr) (int64, error
 					return cursor, nil
 				case ',':
 					idx++
-					continue
 				default:
 					slice.cap = cap
 					slice.data = data
 					d.releaseSlice(slice)
 					return 0, errInvalidCharacter(buf[cursor], "slice", cursor)
 				}
+				cursor++
 			}
 		}
 	}

encode_compile.go

@@ -16,13 +16,14 @@ func (e *Encoder) compileHead(typ *rtype, withIndent bool) (*opcode, error) {
 	if typ.Kind() == reflect.Ptr {
 		typ = typ.Elem()
 	}
+	root := true
 	if typ.Kind() == reflect.Map {
-		return e.compileMap(typ, false, withIndent)
+		return e.compileMap(typ, false, root, withIndent)
 	}
-	return e.compile(typ, withIndent)
+	return e.compile(typ, root, withIndent)
 }
 
-func (e *Encoder) compile(typ *rtype, withIndent bool) (*opcode, error) {
+func (e *Encoder) compile(typ *rtype, root, withIndent bool) (*opcode, error) {
 	if typ.Implements(marshalJSONType) {
 		return newOpCode(opMarshalJSON, typ, e.indent, newEndOp(e.indent)), nil
 	} else if typ.Implements(marshalTextType) {
@@ -30,15 +31,17 @@ func (e *Encoder) compile(typ *rtype, withIndent bool) (*opcode, error) {
 	}
 	switch typ.Kind() {
 	case reflect.Ptr:
-		return e.compilePtr(typ, withIndent)
+		return e.compilePtr(typ, root, withIndent)
 	case reflect.Slice:
-		return e.compileSlice(typ, withIndent)
+		return e.compileSlice(typ, root, withIndent)
 	case reflect.Array:
-		return e.compileArray(typ, withIndent)
+		return e.compileArray(typ, root, withIndent)
 	case reflect.Map:
-		return e.compileMap(typ, true, withIndent)
+		return e.compileMap(typ, true, root, withIndent)
 	case reflect.Struct:
-		return e.compileStruct(typ, withIndent)
+		return e.compileStruct(typ, root, withIndent)
+	case reflect.Interface:
+		return e.compileInterface(typ, root)
 	case reflect.Int:
 		return e.compileInt(typ)
 	case reflect.Int8:
@@ -69,8 +72,6 @@ func (e *Encoder) compile(typ *rtype, withIndent bool) (*opcode, error) {
 		return e.compileString(typ)
 	case reflect.Bool:
 		return e.compileBool(typ)
-	case reflect.Interface:
-		return e.compileInterface(typ)
 	}
 	return nil, &UnsupportedTypeError{Type: rtype2type(typ)}
 }
@@ -204,8 +205,8 @@ func (e *Encoder) optimizeStructFieldPtrHead(typ *rtype, code *opcode) *opcode {
 	return code
 }
 
-func (e *Encoder) compilePtr(typ *rtype, withIndent bool) (*opcode, error) {
+func (e *Encoder) compilePtr(typ *rtype, root, withIndent bool) (*opcode, error) {
-	code, err := e.compile(typ.Elem(), withIndent)
+	code, err := e.compile(typ.Elem(), root, withIndent)
 	if err != nil {
 		return nil, err
 	}
@@ -268,16 +269,24 @@ func (e *Encoder) compileBool(typ *rtype) (*opcode, error) {
 	return newOpCode(opBool, typ, e.indent, newEndOp(e.indent)), nil
 }
 
-func (e *Encoder) compileInterface(typ *rtype) (*opcode, error) {
+func (e *Encoder) compileInterface(typ *rtype, root bool) (*opcode, error) {
-	return newOpCode(opInterface, typ, e.indent, newEndOp(e.indent)), nil
+	return (*opcode)(unsafe.Pointer(&interfaceCode{
+		opcodeHeader: &opcodeHeader{
+			op:     opInterface,
+			typ:    typ,
+			indent: e.indent,
+			next:   newEndOp(e.indent),
+		},
+		root: root,
+	})), nil
 }
 
-func (e *Encoder) compileSlice(typ *rtype, withIndent bool) (*opcode, error) {
+func (e *Encoder) compileSlice(typ *rtype, root, withIndent bool) (*opcode, error) {
 	elem := typ.Elem()
 	size := elem.Size()
 
 	e.indent++
-	code, err := e.compile(elem, withIndent)
+	code, err := e.compile(elem, false, withIndent)
 	e.indent--
 
 	if err != nil {
@@ -298,8 +307,13 @@ func (e *Encoder) compileSlice(typ *rtype, withIndent bool) (*opcode, error) {
 	}
 	end := newOpCode(opSliceEnd, nil, e.indent, newEndOp(e.indent))
 	if withIndent {
-		header.op = opSliceHeadIndent
+		if root {
-		elemCode.op = opSliceElemIndent
+			header.op = opRootSliceHeadIndent
+			elemCode.op = opRootSliceElemIndent
+		} else {
+			header.op = opSliceHeadIndent
+			elemCode.op = opSliceElemIndent
+		}
 		end.op = opSliceEndIndent
 	}
 
@@ -312,13 +326,13 @@ func (e *Encoder) compileSlice(typ *rtype, withIndent bool) (*opcode, error) {
 	return (*opcode)(unsafe.Pointer(header)), nil
 }
 
-func (e *Encoder) compileArray(typ *rtype, withIndent bool) (*opcode, error) {
+func (e *Encoder) compileArray(typ *rtype, root, withIndent bool) (*opcode, error) {
 	elem := typ.Elem()
 	alen := typ.Len()
 	size := elem.Size()
 
 	e.indent++
-	code, err := e.compile(elem, withIndent)
+	code, err := e.compile(elem, false, withIndent)
 	e.indent--
 
 	if err != nil {
@@ -369,18 +383,18 @@ func mapiternext(it unsafe.Pointer)
 //go:noescape
 func maplen(m unsafe.Pointer) int
 
-func (e *Encoder) compileMap(typ *rtype, withLoad, withIndent bool) (*opcode, error) {
+func (e *Encoder) compileMap(typ *rtype, withLoad, root, withIndent bool) (*opcode, error) {
 	// header => code => value => code => key => code => value => code => end
 	//                                     ^                       |
 	//                                     |_______________________|
 	e.indent++
 	keyType := typ.Key()
-	keyCode, err := e.compile(keyType, withIndent)
+	keyCode, err := e.compile(keyType, false, withIndent)
 	if err != nil {
 		return nil, err
 	}
 	valueType := typ.Elem()
-	valueCode, err := e.compile(valueType, withIndent)
+	valueCode, err := e.compile(valueType, false, withIndent)
 	if err != nil {
 		return nil, err
 	}
@@ -397,11 +411,19 @@ func (e *Encoder) compileMap(typ *rtype, withLoad, withIndent bool) (*opcode, er
 
 	if withIndent {
 		if header.op == opMapHead {
-			header.op = opMapHeadIndent
+			if root {
+				header.op = opRootMapHeadIndent
+			} else {
+				header.op = opMapHeadIndent
+			}
 		} else {
 			header.op = opMapHeadLoadIndent
 		}
-		key.op = opMapKeyIndent
+		if root {
+			key.op = opRootMapKeyIndent
+		} else {
+			key.op = opMapKeyIndent
+		}
 		value.op = opMapValueIndent
 		end.op = opMapEndIndent
 	}
@@ -724,7 +746,7 @@ func (e *Encoder) optimizeStructField(op opType, isOmitEmpty, withIndent bool) o
 	return opStructField
 }
 
-func (e *Encoder) compileStruct(typ *rtype, withIndent bool) (*opcode, error) {
+func (e *Encoder) compileStruct(typ *rtype, root, withIndent bool) (*opcode, error) {
 	// header => code => structField => code => end
 	//                        ^          |
 	//                        |__________|
@@ -754,7 +776,7 @@ func (e *Encoder) compileStruct(typ *rtype, withIndent bool) (*opcode, error) {
 			isOmitEmpty = opts[1] == "omitempty"
 		}
 		fieldType := type2rtype(field.Type)
-		valueCode, err := e.compile(fieldType, withIndent)
+		valueCode, err := e.compile(fieldType, false, withIndent)
 		if err != nil {
 			return nil, err
 		}

encode_opcode.go

@@ -35,7 +35,9 @@ const (
 	opSliceEnd
 
 	opSliceHeadIndent
+	opRootSliceHeadIndent
 	opSliceElemIndent
+	opRootSliceElemIndent
 	opSliceEndIndent
 
 	opArrayHead
@@ -50,12 +52,14 @@ const (
 	opMapHeadLoad
 	opMapKey
 	opMapValue
-	opMapEnd
 
 	opMapHeadIndent
+	opRootMapHeadIndent
 	opMapHeadLoadIndent
 	opMapKeyIndent
+	opRootMapKeyIndent
 	opMapValueIndent
+	opMapEnd
 	opMapEndIndent
 
 	// StructFieldHead
@@ -310,8 +314,12 @@ func (t opType) String() string {
 
 	case opSliceHeadIndent:
 		return "SLICE_HEAD_INDENT"
+	case opRootSliceHeadIndent:
+		return "ROOT_SLICE_HEAD_INDENT"
 	case opSliceElemIndent:
 		return "SLICE_ELEM_INDENT"
+	case opRootSliceElemIndent:
+		return "ROOT_SLICE_ELEM_INDENT"
 	case opSliceEndIndent:
 		return "SLICE_END_INDENT"
 
@@ -341,10 +349,14 @@ func (t opType) String() string {
 
 	case opMapHeadIndent:
 		return "MAP_HEAD_INDENT"
+	case opRootMapHeadIndent:
+		return "ROOT_MAP_HEAD_INDENT"
 	case opMapHeadLoadIndent:
 		return "MAP_HEAD_LOAD_INDENT"
 	case opMapKeyIndent:
 		return "MAP_KEY_INDENT"
+	case opRootMapKeyIndent:
+		return "ROOT_MAP_KEY_INDENT"
 	case opMapValueIndent:
 		return "MAP_VALUE_INDENT"
 	case opMapEndIndent:
@@ -780,9 +792,9 @@ func (c *opcode) beforeLastCode() *opcode {
 		switch code.op {
 		case opArrayElem, opArrayElemIndent:
 			nextCode = code.toArrayElemCode().end
-		case opSliceElem, opSliceElemIndent:
+		case opSliceElem, opSliceElemIndent, opRootSliceElemIndent:
 			nextCode = code.toSliceElemCode().end
-		case opMapKey, opMapKeyIndent:
+		case opMapKey, opMapKeyIndent, opRootMapKeyIndent:
 			nextCode = code.toMapKeyCode().end
 		default:
 			nextCode = code.next
@@ -809,13 +821,13 @@ func (c *opcode) copy(codeMap map[uintptr]*opcode) *opcode {
 		code = c.toArrayHeaderCode().copy(codeMap)
 	case opArrayElem, opArrayElemIndent:
 		code = c.toArrayElemCode().copy(codeMap)
-	case opSliceHead, opSliceHeadIndent:
+	case opSliceHead, opSliceHeadIndent, opRootSliceHeadIndent:
 		code = c.toSliceHeaderCode().copy(codeMap)
-	case opSliceElem, opSliceElemIndent:
+	case opSliceElem, opSliceElemIndent, opRootSliceElemIndent:
 		code = c.toSliceElemCode().copy(codeMap)
-	case opMapHead, opMapHeadLoad, opMapHeadIndent, opMapHeadLoadIndent:
+	case opMapHead, opMapHeadLoad, opMapHeadIndent, opMapHeadLoadIndent, opRootMapHeadIndent:
 		code = c.toMapHeadCode().copy(codeMap)
-	case opMapKey, opMapKeyIndent:
+	case opMapKey, opMapKeyIndent, opRootMapKeyIndent:
 		code = c.toMapKeyCode().copy(codeMap)
 	case opMapValue, opMapValueIndent:
 		code = c.toMapValueCode().copy(codeMap)
@@ -1017,9 +1029,9 @@ func (c *opcode) dump() string {
 		switch code.op {
 		case opArrayElem, opArrayElemIndent:
 			code = code.toArrayElemCode().end
-		case opSliceElem, opSliceElemIndent:
+		case opSliceElem, opSliceElemIndent, opRootSliceElemIndent:
 			code = code.toSliceElemCode().end
-		case opMapKey, opMapKeyIndent:
+		case opMapKey, opMapKeyIndent, opRootMapKeyIndent:
 			code = code.toMapKeyCode().end
 		default:
 			code = code.next
@@ -1060,6 +1072,10 @@ func (c *opcode) toMapValueCode() *mapValueCode {
 	return (*mapValueCode)(unsafe.Pointer(c))
 }
 
+func (c *opcode) toInterfaceCode() *interfaceCode {
+	return (*interfaceCode)(unsafe.Pointer(c))
+}
+
 type sliceHeaderCode struct {
 	*opcodeHeader
 	elem *sliceElemCode
@@ -1285,6 +1301,27 @@ func (c *mapKeyCode) set(len int, iter unsafe.Pointer) {
 	c.iter = iter
 }
 
+type interfaceCode struct {
+	*opcodeHeader
+	root bool
+}
+
+func (c *interfaceCode) copy(codeMap map[uintptr]*opcode) *opcode {
+	if c == nil {
+		return nil
+	}
+	addr := uintptr(unsafe.Pointer(c))
+	if code, exists := codeMap[addr]; exists {
+		return code
+	}
+	iface := &interfaceCode{}
+	code := (*opcode)(unsafe.Pointer(iface))
+	codeMap[addr] = code
+
+	iface.opcodeHeader = c.opcodeHeader.copy(codeMap)
+	return code
+}
+
 type mapValueCode struct {
 	*opcodeHeader
 	iter unsafe.Pointer

encode_vm.go

@@ -65,19 +65,26 @@ func (e *Encoder) run(code *opcode) error {
 			e.encodeBool(e.ptrToBool(code.ptr))
 			code = code.next
 		case opInterface:
-			ptr := code.ptr
+			ifaceCode := code.toInterfaceCode()
+			ptr := ifaceCode.ptr
 			v := *(*interface{})(unsafe.Pointer(&interfaceHeader{
-				typ: code.typ,
+				typ: ifaceCode.typ,
 				ptr: unsafe.Pointer(ptr),
 			}))
-			vv := reflect.ValueOf(v).Interface()
+			rv := reflect.ValueOf(v)
+			if rv.IsNil() {
+				e.encodeNull()
+				code = ifaceCode.next
+				break
+			}
+			vv := rv.Interface()
 			header := (*interfaceHeader)(unsafe.Pointer(&vv))
 			typ := header.typ
 			if typ.Kind() == reflect.Ptr {
 				typ = typ.Elem()
 			}
-			e.indent = code.indent
+			e.indent = ifaceCode.indent
-			c, err := e.compile(typ, e.enabledIndent)
+			c, err := e.compile(typ, ifaceCode.root, e.enabledIndent)
 			if err != nil {
 				return err
 			}
@@ -153,17 +160,37 @@ func (e *Encoder) run(code *opcode) error {
 				e.encodeNull()
 				code = headerCode.end.next
 			} else {
-				e.encodeBytes([]byte{'[', '\n'})
 				header := (*reflect.SliceHeader)(unsafe.Pointer(p))
 				headerCode.elem.set(header)
 				if header.Len > 0 {
+					e.encodeBytes([]byte{'[', '\n'})
 					e.encodeIndent(code.indent + 1)
 					code = code.next
 					code.ptr = header.Data
 				} else {
-					e.encodeByte('\n')
 					e.encodeIndent(code.indent)
-					e.encodeBytes([]byte{']', '\n'})
+					e.encodeBytes([]byte{'[', ']', '\n'})
+					code = headerCode.end.next
+				}
+			}
+		case opRootSliceHeadIndent:
+			p := code.ptr
+			headerCode := code.toSliceHeaderCode()
+			if p == 0 {
+				e.encodeIndent(code.indent)
+				e.encodeNull()
+				code = headerCode.end.next
+			} else {
+				header := (*reflect.SliceHeader)(unsafe.Pointer(p))
+				headerCode.elem.set(header)
+				if header.Len > 0 {
+					e.encodeBytes([]byte{'[', '\n'})
+					e.encodeIndent(code.indent + 1)
+					code = code.next
+					code.ptr = header.Data
+				} else {
+					e.encodeIndent(code.indent)
+					e.encodeBytes([]byte{'[', ']'})
 					code = headerCode.end.next
 				}
 			}
@@ -181,6 +208,20 @@ func (e *Encoder) run(code *opcode) error {
 				e.encodeBytes([]byte{']', '\n'})
 				code = c.end.next
 			}
+		case opRootSliceElemIndent:
+			c := code.toSliceElemCode()
+			c.idx++
+			if c.idx < c.len {
+				e.encodeBytes([]byte{',', '\n'})
+				e.encodeIndent(code.indent + 1)
+				code = code.next
+				code.ptr = c.data + c.idx*c.size
+			} else {
+				e.encodeByte('\n')
+				e.encodeIndent(code.indent)
+				e.encodeBytes([]byte{']'})
+				code = c.end.next
+			}
 		case opArrayHead:
 			p := code.ptr
 			headerCode := code.toArrayHeaderCode()
@@ -287,7 +328,6 @@ func (e *Encoder) run(code *opcode) error {
 					code = mapHeadCode.end.next
 				}
 			}
-
 		case opMapKey:
 			c := code.toMapKeyCode()
 			c.idx++
@@ -315,9 +355,9 @@ func (e *Encoder) run(code *opcode) error {
 				e.encodeNull()
 				code = mapHeadCode.end.next
 			} else {
-				e.encodeBytes([]byte{'{', '\n'})
 				mlen := maplen(unsafe.Pointer(ptr))
 				if mlen > 0 {
+					e.encodeBytes([]byte{'{', '\n'})
 					iter := mapiterinit(code.typ, unsafe.Pointer(ptr))
 					mapHeadCode.key.set(mlen, iter)
 					mapHeadCode.value.set(iter)
@@ -326,9 +366,58 @@ func (e *Encoder) run(code *opcode) error {
 					code = code.next
 					e.encodeIndent(code.indent)
 				} else {
-					e.encodeByte('\n')
+					e.encodeIndent(code.indent)
-					e.encodeIndent(code.indent - 1)
+					e.encodeBytes([]byte{'{', '}', '\n'})
-					e.encodeBytes([]byte{'}', '\n'})
+					code = mapHeadCode.end.next
+				}
+			}
+		case opMapHeadLoadIndent:
+			ptr := code.ptr
+			mapHeadCode := code.toMapHeadCode()
+			if ptr == 0 {
+				e.encodeIndent(code.indent)
+				e.encodeNull()
+				code = mapHeadCode.end.next
+			} else {
+				// load pointer
+				ptr = uintptr(*(*unsafe.Pointer)(unsafe.Pointer(ptr)))
+				mlen := maplen(unsafe.Pointer(ptr))
+				if mlen > 0 {
+					e.encodeBytes([]byte{'{', '\n'})
+					iter := mapiterinit(code.typ, unsafe.Pointer(ptr))
+					mapHeadCode.key.set(mlen, iter)
+					mapHeadCode.value.set(iter)
+					key := mapiterkey(iter)
+					code.next.ptr = uintptr(key)
+					code = code.next
+					e.encodeIndent(code.indent)
+				} else {
+					e.encodeIndent(code.indent)
+					e.encodeBytes([]byte{'{', '}', '\n'})
+					code = mapHeadCode.end.next
+				}
+			}
+		case opRootMapHeadIndent:
+			ptr := code.ptr
+			mapHeadCode := code.toMapHeadCode()
+			if ptr == 0 {
+				e.encodeIndent(code.indent)
+				e.encodeNull()
+				code = mapHeadCode.end.next
+			} else {
+				mlen := maplen(unsafe.Pointer(ptr))
+				if mlen > 0 {
+					e.encodeBytes([]byte{'{', '\n'})
+					iter := mapiterinit(code.typ, unsafe.Pointer(ptr))
+					mapHeadCode.key.set(mlen, iter)
+					mapHeadCode.value.set(iter)
+					key := mapiterkey(iter)
+					code.next.ptr = uintptr(key)
+					code = code.next
+					e.encodeIndent(code.indent)
+				} else {
+					e.encodeIndent(code.indent)
+					e.encodeBytes([]byte{'{', '}'})
 					code = mapHeadCode.end.next
 				}
 			}
@@ -347,6 +436,21 @@ func (e *Encoder) run(code *opcode) error {
 				e.encodeBytes([]byte{'}', '\n'})
 				code = c.end.next
 			}
+		case opRootMapKeyIndent:
+			c := code.toMapKeyCode()
+			c.idx++
+			if c.idx < c.len {
+				e.encodeBytes([]byte{',', '\n'})
+				e.encodeIndent(code.indent)
+				key := mapiterkey(c.iter)
+				c.next.ptr = uintptr(key)
+				code = c.next
+			} else {
+				e.encodeByte('\n')
+				e.encodeIndent(code.indent - 1)
+				e.encodeBytes([]byte{'}'})
+				code = c.end.next
+			}
 		case opMapValueIndent:
 			e.encodeBytes([]byte{':', ' '})
 			c := code.toMapValueCode()

json.go

@@ -296,6 +296,10 @@ func (n Number) Int64() (int64, error) {
 	return strconv.ParseInt(string(n), 10, 64)
 }
 
+func (n Number) MarshalJSON() ([]byte, error) {
+	return []byte(n), nil
+}
+
 // RawMessage is a raw encoded JSON value.
 // It implements Marshaler and Unmarshaler and can
 // be used to delay JSON decoding or precompute a JSON encoding.
@@ -317,3 +321,68 @@ func (m *RawMessage) UnmarshalJSON(data []byte) error {
 	*m = append((*m)[0:0], data...)
 	return nil
 }
+
+// Compact appends to dst the JSON-encoded src with
+// insignificant space characters elided.
+func Compact(dst *bytes.Buffer, src []byte) error {
+	var v interface{}
+	dec := NewDecoder(bytes.NewBuffer(src))
+	dec.UseNumber()
+	if err := dec.Decode(&v); err != nil {
+		return err
+	}
+	enc := NewEncoder(dst)
+	enc.SetEscapeHTML(false)
+	return enc.Encode(v)
+}
+
+// Indent appends to dst an indented form of the JSON-encoded src.
+// Each element in a JSON object or array begins on a new,
+// indented line beginning with prefix followed by one or more
+// copies of indent according to the indentation nesting.
+// The data appended to dst does not begin with the prefix nor
+// any indentation, to make it easier to embed inside other formatted JSON data.
+// Although leading space characters (space, tab, carriage return, newline)
+// at the beginning of src are dropped, trailing space characters
+// at the end of src are preserved and copied to dst.
+// For example, if src has no trailing spaces, neither will dst;
+// if src ends in a trailing newline, so will dst.
+func Indent(dst *bytes.Buffer, src []byte, prefix, indent string) error {
+	var v interface{}
+	dec := NewDecoder(bytes.NewBuffer(src))
+	dec.UseNumber()
+	if err := dec.Decode(&v); err != nil {
+		return err
+	}
+	enc := NewEncoder(dst)
+	enc.SetEscapeHTML(false)
+	enc.SetIndent(prefix, indent)
+	return enc.Encode(v)
+}
+
+// HTMLEscape appends to dst the JSON-encoded src with <, >, &, U+2028 and U+2029
+// characters inside string literals changed to \u003c, \u003e, \u0026, \u2028, \u2029
+// so that the JSON will be safe to embed inside HTML <script> tags.
+// For historical reasons, web browsers don't honor standard HTML
+// escaping within <script> tags, so an alternative JSON encoding must
+// be used.
+func HTMLEscape(dst *bytes.Buffer, src []byte) {
+	var v interface{}
+	dec := NewDecoder(bytes.NewBuffer(src))
+	dec.UseNumber()
+	if err := dec.Decode(&v); err != nil {
+		return
+	}
+	enc := NewEncoder(dst)
+	enc.SetEscapeHTML(true)
+	enc.Encode(v)
+}
+
+// Valid reports whether data is a valid JSON encoding.
+func Valid(data []byte) bool {
+	var v interface{}
+	if err := Unmarshal(data, &v); err != nil {
+		return false
+	}
+	return true
+}

json_test.go

@@ -0,0 +1,118 @@
+package json_test
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/goccy/go-json"
+)
+
+var validTests = []struct {
+	data string
+	ok   bool
+}{
+	{`foo`, false},
+	{`}{`, false},
+	{`{]`, false},
+	{`{}`, true},
+	{`{"foo":"bar"}`, true},
+	{`{"foo":"bar","bar":{"baz":["qux"]}}`, true},
+}
+
+func TestValid(t *testing.T) {
+	for _, tt := range validTests {
+		if ok := json.Valid([]byte(tt.data)); ok != tt.ok {
+			t.Errorf("Valid(%#q) = %v, want %v", tt.data, ok, tt.ok)
+		}
+	}
+}
+
+type example struct {
+	compact string
+	indent  string
+}
+
+var examples = []example{
+	{`1`, `1`},
+	{`{}`, `{}`},
+	{`[]`, `[]`},
+	{`{"":2}`, "{\n\t\"\": 2\n}"},
+	{`[3]`, "[\n\t3\n]"},
+	{`[1,2,3]`, "[\n\t1,\n\t2,\n\t3\n]"},
+	{`{"x":1}`, "{\n\t\"x\": 1\n}"},
+	{ex1, ex1i},
+	{"{\"\":\"<>&\u2028\u2029\"}", "{\n\t\"\": \"<>&\u2028\u2029\"\n}"}, // See golang.org/issue/34070
+}
+
+var ex1 = `[true,false,null,"x",1,1.5,0,-5e+2]`
+
+var ex1i = `[
+	true,
+	false,
+	null,
+	"x",
+	1,
+	1.5,
+	0,
+	-5e+2
+]`
+
+func TestCompact(t *testing.T) {
+	var buf bytes.Buffer
+	for _, tt := range examples {
+		buf.Reset()
+		t.Log("src = ", tt.compact)
+		if err := json.Compact(&buf, []byte(tt.compact)); err != nil {
+			t.Errorf("Compact(%#q): %v", tt.compact, err)
+		} else if s := buf.String(); s != tt.compact {
+			t.Errorf("Compact(%#q) = %#q, want original", tt.compact, s)
+		}
+
+		buf.Reset()
+		if err := json.Compact(&buf, []byte(tt.indent)); err != nil {
+			t.Errorf("Compact(%#q): %v", tt.indent, err)
+			continue
+		} else if s := buf.String(); s != tt.compact {
+			t.Errorf("Compact(%#q) = %#q, want %#q", tt.indent, s, tt.compact)
+		}
+	}
+}
+
+func TestCompactSeparators(t *testing.T) {
+	// U+2028 and U+2029 should be escaped inside strings.
+	// They should not appear outside strings.
+	tests := []struct {
+		in, compact string
+	}{
+		{"{\"\u2028\": 1}", "{\"\u2028\":1}"},
+		{"{\"\u2029\" :2}", "{\"\u2029\":2}"},
+	}
+	for _, tt := range tests {
+		var buf bytes.Buffer
+		if err := json.Compact(&buf, []byte(tt.in)); err != nil {
+			t.Errorf("Compact(%q): %v", tt.in, err)
+		} else if s := buf.String(); s != tt.compact {
+			t.Errorf("Compact(%q) = %q, want %q", tt.in, s, tt.compact)
+		}
+	}
+}
+
+func TestIndent(t *testing.T) {
+	var buf bytes.Buffer
+	for _, tt := range examples {
+		buf.Reset()
+		if err := json.Indent(&buf, []byte(tt.indent), "", "\t"); err != nil {
+			t.Errorf("Indent(%#q): %v", tt.indent, err)
+		} else if s := buf.String(); s != tt.indent {
+			t.Errorf("Indent(%#q) = %#q, want original", tt.indent, s)
+		}
+
+		buf.Reset()
+		if err := json.Indent(&buf, []byte(tt.compact), "", "\t"); err != nil {
+			t.Errorf("Indent(%#q): %v", tt.compact, err)
+			continue
+		} else if s := buf.String(); s != tt.indent {
+			t.Errorf("Indent(%#q) = %#q, want %#q", tt.compact, s, tt.indent)
+		}
+	}
+}