Use ReadStringAsSlice instead of ReadString

any.go

@@ -3,11 +3,12 @@ package jsoniter
 import (
 	"errors"
 	"fmt"
-	"github.com/modern-go/reflect2"
 	"io"
 	"reflect"
 	"strconv"
 	"unsafe"
+
+	"github.com/modern-go/reflect2"
 )
 
 // Any generic object representation.
@@ -155,7 +156,7 @@ func (iter *Iterator) readAny() Any {
 	switch c {
 	case '"':
 		iter.unreadByte()
-		return &stringAny{baseAny{}, iter.ReadString()}
+		return &stringAny{baseAny{}, string(iter.ReadStringAsSlice())}
 	case 'n':
 		iter.skipThreeBytes('u', 'l', 'l') // null
 		return &nilAny{}

extra/binary_as_string_codec.go

@@ -1,10 +1,12 @@
 package extra
 
 import (
-	"github.com/json-iterator/go"
-	"github.com/modern-go/reflect2"
 	"unicode/utf8"
 	"unsafe"
+
+	"github.com/modern-go/reflect2"
+
+	"github.com/json-iterator/go"
 )
 
 // safeSet holds the value true if the ASCII character with the given array
@@ -142,19 +144,14 @@ func (codec *binaryAsStringCodec) Decode(ptr unsafe.Pointer, iter *jsoniter.Iter
 		b := rawBytes[i]
 		if b == '\\' {
 			b2 := rawBytes[i+1]
-			if b2 != '\\' {
-				iter.ReportError("decode binary as string", `\\x is only supported escape`)
+			if b2 != 'x' {
+				iter.ReportError("decode binary as string", `\x is only supported escape`)
 				return
 			}
 			b3 := rawBytes[i+2]
-			if b3 != 'x' {
-				iter.ReportError("decode binary as string", `\\x is only supported escape`)
-				return
-			}
 			b4 := rawBytes[i+3]
-			b5 := rawBytes[i+4]
-			i += 4
-			b = readHex(iter, b4, b5)
+			i += 3
+			b = readHex(iter, b3, b4)
 		}
 		bytes = append(bytes, b)
 	}

iter_object.go

@@ -59,7 +59,7 @@ func (iter *Iterator) readFieldHash() int64 {
 			b := iter.buf[i]
 			if b == '\\' {
 				iter.head = i
-				for _, b := range iter.readStringSlowPath() {
+				for _, b := range iter.readStringSlowPathAsSlice() {
 					if 'A' <= b && b <= 'Z' && !iter.cfg.caseSensitive {
 						b += 'a' - 'A'
 					}
@@ -110,31 +110,30 @@ func calcHash(str string, caseSensitive bool) int64 {
 // ReadObjectCB read object with callback, the key is ascii only and field name not copied
 func (iter *Iterator) ReadObjectCB(callback func(*Iterator, string) bool) bool {
 	c := iter.nextToken()
-	var field string
 	if c == '{' {
 		if !iter.incrementDepth() {
 			return false
 		}
 		c = iter.nextToken()
 		if c == '"' {
 			iter.unreadByte()
-			field = iter.ReadString()
+			field := iter.ReadStringAsSlice()
 			c = iter.nextToken()
 			if c != ':' {
 				iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
 			}
-			if !callback(iter, field) {
+			if !callback(iter, string(field)) {
 				iter.decrementDepth()
 				return false
 			}
 			c = iter.nextToken()
 			for c == ',' {
-				field = iter.ReadString()
+				field = iter.ReadStringAsSlice()
 				c = iter.nextToken()
 				if c != ':' {
 					iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
 				}
-				if !callback(iter, field) {
+				if !callback(iter, string(field)) {
 					iter.decrementDepth()
 					return false
 				}
@@ -172,25 +171,25 @@ func (iter *Iterator) ReadMapCB(callback func(*Iterator, string) bool) bool {
 		c = iter.nextToken()
 		if c == '"' {
 			iter.unreadByte()
-			field := iter.ReadString()
+			field := iter.ReadStringAsSlice()
 			if iter.nextToken() != ':' {
 				iter.ReportError("ReadMapCB", "expect : after object field, but found "+string([]byte{c}))
 				iter.decrementDepth()
 				return false
 			}
-			if !callback(iter, field) {
+			if !callback(iter, string(field)) {
 				iter.decrementDepth()
 				return false
 			}
 			c = iter.nextToken()
 			for c == ',' {
-				field = iter.ReadString()
+				field = iter.ReadStringAsSlice()
 				if iter.nextToken() != ':' {
 					iter.ReportError("ReadMapCB", "expect : after object field, but found "+string([]byte{c}))
 					iter.decrementDepth()
 					return false
 				}
-				if !callback(iter, field) {
+				if !callback(iter, string(field)) {
 					iter.decrementDepth()
 					return false
 				}

iter_skip_strict.go

@@ -1,4 +1,5 @@
-//+build !jsoniter_sloppy
+//go:build !jsoniter_sloppy
+// +build !jsoniter_sloppy
 
 package jsoniter
 
@@ -61,7 +62,7 @@ func (iter *Iterator) trySkipNumber() bool {
 func (iter *Iterator) skipString() {
 	if !iter.trySkipString() {
 		iter.unreadByte()
-		iter.ReadString()
+		iter.ReadStringAsSlice()
 	}
 }
 

iter_str.go

@@ -7,38 +7,44 @@ import (
 
 // ReadString read string from iterator
 func (iter *Iterator) ReadString() (ret string) {
+	return string(iter.ReadStringAsSlice())
+}
+
+// ReadStringAsSlice read string from iterator without copying into string form.
+// The []byte can not be kept, as it will change after next iterator call.
+func (iter *Iterator) ReadStringAsSlice() (ret []byte) {
 	c := iter.nextToken()
 	if c == '"' {
 		for i := iter.head; i < iter.tail; i++ {
 			c := iter.buf[i]
 			if c == '"' {
-				ret = string(iter.buf[iter.head:i])
+				head := iter.head
 				iter.head = i + 1
-				return ret
+				return iter.buf[head:i]
 			} else if c == '\\' {
 				break
 			} else if c < ' ' {
-				iter.ReportError("ReadString",
+				iter.ReportError("ReadStringAsSlice",
 					fmt.Sprintf(`invalid control character found: %d`, c))
 				return
 			}
 		}
-		return iter.readStringSlowPath()
+		return iter.readStringSlowPathAsSlice()
 	} else if c == 'n' {
 		iter.skipThreeBytes('u', 'l', 'l')
-		return ""
+		return
 	}
-	iter.ReportError("ReadString", `expects " or n, but found `+string([]byte{c}))
+	iter.ReportError("ReadStringAsSlice", `expects " or n, but found `+string([]byte{c}))
 	return
 }
 
-func (iter *Iterator) readStringSlowPath() (ret string) {
+func (iter *Iterator) readStringSlowPathAsSlice() (ret []byte) {
 	var str []byte
 	var c byte
 	for iter.Error == nil {
 		c = iter.readByte()
 		if c == '"' {
-			return string(str)
+			return str
 		}
 		if c == '\\' {
 			c = iter.readByte()
@@ -47,7 +53,7 @@ func (iter *Iterator) readStringSlowPath() (ret string) {
 			str = append(str, c)
 		}
 	}
-	iter.ReportError("readStringSlowPath", "unexpected end of input")
+	iter.ReportError("readStringSlowPathAsSlice", "unexpected end of input")
 	return
 }
 
@@ -111,38 +117,6 @@ func (iter *Iterator) readEscapedChar(c byte, str []byte) []byte {
 	return str
 }
 
-// ReadStringAsSlice read string from iterator without copying into string form.
-// The []byte can not be kept, as it will change after next iterator call.
-func (iter *Iterator) ReadStringAsSlice() (ret []byte) {
-	c := iter.nextToken()
-	if c == '"' {
-		for i := iter.head; i < iter.tail; i++ {
-			// require ascii string and no escape
-			// for: field name, base64, number
-			if iter.buf[i] == '"' {
-				// fast path: reuse the underlying buffer
-				ret = iter.buf[iter.head:i]
-				iter.head = i + 1
-				return ret
-			}
-		}
-		readLen := iter.tail - iter.head
-		copied := make([]byte, readLen, readLen*2)
-		copy(copied, iter.buf[iter.head:iter.tail])
-		iter.head = iter.tail
-		for iter.Error == nil {
-			c := iter.readByte()
-			if c == '"' {
-				return copied
-			}
-			copied = append(copied, c)
-		}
-		return copied
-	}
-	iter.ReportError("ReadStringAsSlice", `expects " or n, but found `+string([]byte{c}))
-	return
-}
-
 func (iter *Iterator) readU4() (ret rune) {
 	for i := 0; i < 4; i++ {
 		c := iter.readByte()

misc_tests/jsoniter_object_test.go

@@ -3,12 +3,13 @@ package misc_tests
 import (
 	"bytes"
 	"reflect"
+	"strings"
 	"testing"
+	"time"
 
-	"github.com/json-iterator/go"
 	"github.com/stretchr/testify/require"
-	"strings"
-	"time"
+
+	"github.com/json-iterator/go"
 )
 
 func Test_empty_object(t *testing.T) {

reflect_json_number.go

@@ -2,9 +2,10 @@ package jsoniter
 
 import (
 	"encoding/json"
-	"github.com/modern-go/reflect2"
 	"strconv"
 	"unsafe"
+
+	"github.com/modern-go/reflect2"
 )
 
 type Number string
@@ -61,7 +62,7 @@ type jsonNumberCodec struct {
 func (codec *jsonNumberCodec) Decode(ptr unsafe.Pointer, iter *Iterator) {
 	switch iter.WhatIsNext() {
 	case StringValue:
-		*((*json.Number)(ptr)) = json.Number(iter.ReadString())
+		*((*json.Number)(ptr)) = json.Number(iter.ReadStringAsSlice())
 	case NilValue:
 		iter.skipFourBytes('n', 'u', 'l', 'l')
 		*((*json.Number)(ptr)) = ""
@@ -89,12 +90,14 @@ type jsoniterNumberCodec struct {
 func (codec *jsoniterNumberCodec) Decode(ptr unsafe.Pointer, iter *Iterator) {
 	switch iter.WhatIsNext() {
 	case StringValue:
-		*((*Number)(ptr)) = Number(iter.ReadString())
+		num := iter.ReadStringAsSlice()
+		*((*Number)(ptr)) = Number(string(num))
 	case NilValue:
 		iter.skipFourBytes('n', 'u', 'l', 'l')
 		*((*Number)(ptr)) = ""
 	default:
-		*((*Number)(ptr)) = Number([]byte(iter.readNumberAsString()))
+		num := iter.ReadStringAsSlice()
+		*((*Number)(ptr)) = Number(string(num))
 	}
 }
 

reflect_map.go

@@ -305,7 +305,7 @@ func (encoder *sortKeysMapEncoder) Encode(ptr unsafe.Pointer, stream *Stream) {
 		}
 		encodedKey := subStream.Buffer()[subStreamIndex:]
 		subIter.ResetBytes(encodedKey)
-		decodedKey := subIter.ReadString()
+		decodedKey := string(subIter.ReadStringAsSlice())
 		if stream.indention > 0 {
 			subStream.writeTwoBytes(byte(':'), byte(' '))
 		} else {

reflect_marshaler.go

@@ -217,8 +217,8 @@ func (decoder *textUnmarshalerDecoder) Decode(ptr unsafe.Pointer, iter *Iterator
 		obj = valType.UnsafeIndirect(ptr)
 	}
 	unmarshaler := (obj).(encoding.TextUnmarshaler)
-	str := iter.ReadString()
-	err := unmarshaler.UnmarshalText([]byte(str))
+	str := iter.ReadStringAsSlice()
+	err := unmarshaler.UnmarshalText(str)
 	if err != nil {
 		iter.ReportError("textUnmarshalerDecoder", err.Error())
 	}

reflect_native.go

@@ -206,7 +206,8 @@ type stringCodec struct {
 }
 
 func (codec *stringCodec) Decode(ptr unsafe.Pointer, iter *Iterator) {
-	*((*string)(ptr)) = iter.ReadString()
+	data := iter.ReadStringAsSlice()
+	*((*string)(ptr)) = string(data)
 }
 
 func (codec *stringCodec) Encode(ptr unsafe.Pointer, stream *Stream) {
@@ -417,8 +418,8 @@ func (codec *base64Codec) Decode(ptr unsafe.Pointer, iter *Iterator) {
 	}
 	switch iter.WhatIsNext() {
 	case StringValue:
-		src := iter.ReadString()
-		dst, err := base64.StdEncoding.DecodeString(src)
+		src := iter.ReadStringAsSlice()
+		dst, err := base64.StdEncoding.DecodeString(string(src))
 		if err != nil {
 			iter.ReportError("decode base64", err.Error())
 		} else {

reflect_struct_decoder.go

@@ -517,21 +517,10 @@ func (decoder *generalStructDecoder) Decode(ptr unsafe.Pointer, iter *Iterator)
 }
 
 func (decoder *generalStructDecoder) decodeOneField(ptr unsafe.Pointer, iter *Iterator) {
-	var field string
-	var fieldDecoder *structFieldDecoder
-	if iter.cfg.objectFieldMustBeSimpleString {
-		fieldBytes := iter.ReadStringAsSlice()
-		field = *(*string)(unsafe.Pointer(&fieldBytes))
-		fieldDecoder = decoder.fields[field]
-		if fieldDecoder == nil && !iter.cfg.caseSensitive {
-			fieldDecoder = decoder.fields[strings.ToLower(field)]
-		}
-	} else {
-		field = iter.ReadString()
-		fieldDecoder = decoder.fields[field]
-		if fieldDecoder == nil && !iter.cfg.caseSensitive {
-			fieldDecoder = decoder.fields[strings.ToLower(field)]
-		}
+	field := string(iter.ReadStringAsSlice())
+	fieldDecoder := decoder.fields[field]
+	if fieldDecoder == nil && !iter.cfg.caseSensitive {
+		fieldDecoder = decoder.fields[strings.ToLower(field)]
 	}
 	if fieldDecoder == nil {
 		if decoder.disallowUnknownFields {
@@ -1067,7 +1056,8 @@ func (decoder *stringModeStringDecoder) Decode(ptr unsafe.Pointer, iter *Iterato
 	str := *((*string)(ptr))
 	tempIter := decoder.cfg.BorrowIterator([]byte(str))
 	defer decoder.cfg.ReturnIterator(tempIter)
-	*((*string)(ptr)) = tempIter.ReadString()
+	data := tempIter.ReadStringAsSlice()
+	*((*string)(ptr)) = string(data)
 }
 
 type stringModeNumberDecoder struct {