[*] feat: remove some string() conversion to cut off unmarshal time

conv.go

@@ -8,19 +8,18 @@ import (
 	"unicode"
 	"unicode/utf16"
 	"unicode/utf8"
-	"unsafe"
 )
 
 func parseUint(b []byte) (uint64, error) {
-	return strconv.ParseUint(string(b), 10, 64)
+	return strconv.ParseUint(unsafeBtoS(b), 10, 64)
 }
 
 func parseInt(b []byte) (int64, error) {
-	return strconv.ParseInt(string(b), 10, 64)
+	return strconv.ParseInt(unsafeBtoS(b), 10, 64)
 }
 
 func parseFloat(b []byte) (float64, error) {
-	return strconv.ParseFloat(string(b), 64)
+	return strconv.ParseFloat(unsafeBtoS(b), 64)
 }
 
 // reference: https://golang.org/src/encoding/json/decode.go, func unquote()
@@ -35,17 +34,19 @@ func parseString(b []byte) (string, []byte, error) {
 
 	t, ok := unquoteBytes(b)
 	if !ok {
-		return "", nil, fmt.Errorf("invalid string '%s'", string(b))
+		return "", nil, fmt.Errorf("invalid string '%s'", unsafeBtoS(b))
 	}
-	return string(t), b, nil
+	return unsafeBtoS(t), b, nil
 }
 
 func unquoteBytes(s []byte) (t []byte, ok bool) {
 	if len(s) < 2 || s[0] != '"' || s[len(s)-1] != '"' {
 		return
 	}
-	s = s[1 : len(s)-1]
+	return parseStrText(s[1 : len(s)-1])
+}
 
+func parseStrText(s []byte) (t []byte, ok bool) {
 	// Check for unusual characters. If there are none,
 	// then no unquoting is needed, so return a slice of the
 	// original bytes.
@@ -176,19 +177,25 @@ func getu4(s []byte) rune {
 }
 
 func parseStringNoQuote(b []byte) (string, error) {
-	if len(b) == 0 {
-		return "", nil
-	}
-	s := unsafe.Sizeof(b[0])
-	sh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
-	bh := reflect.SliceHeader{
-		Data: sh.Data - s,
-		Len:  sh.Len + int(s+s),
-		Cap:  sh.Len + int(s+s),
+	// if len(b) == 0 {
+	// 	return "", nil
+	// }
+	// s := unsafe.Sizeof(b[0])
+	// sh := (*reflect.SliceHeader)(unsafe.Pointer(&b))
+	// bh := &reflect.SliceHeader{
+	// 	Data: sh.Data - s,
+	// 	Len:  sh.Len + int(s+s),
+	// 	Cap:  sh.Len + int(s+s),
+	// }
+	// b = *(*[]byte)(unsafe.Pointer(bh))
+	// str, _, err := parseString(b)
+	// return str, err
+
+	t, ok := parseStrText(b)
+	if !ok {
+		return "", fmt.Errorf("invalid string '%s'", string(b))
 	}
-	b = *(*[]byte)(unsafe.Pointer(&bh))
-	str, _, err := parseString(b)
-	return str, err
+	return unsafeBtoS(t), nil
 }
 
 func formatBool(b bool) string {

jsonvalue.go

@@ -130,9 +130,9 @@ func (v *V) delCaselessKey(k string) {
 	}
 }
 
-// UnmarshalString is equavilent to Unmarshal(string(b)), but much more efficient.
+// UnmarshalString is equavilent to Unmarshal(unsafeBtoS(b)), but much more efficient.
 //
-// UnmarshalString 等效于 Unmarshal(string(b))，但效率更高。
+// UnmarshalString 等效于 Unmarshal(unsafeBtoS(b))，但效率更高。
 func UnmarshalString(s string) (*V, error) {
 	// reference: https://stackoverflow.com/questions/41591097/slice-bounds-out-of-range-when-using-unsafe-pointer
 	// sh := (*reflect.StringHeader)(unsafe.Pointer(&s))
@@ -199,14 +199,16 @@ func Unmarshal(b []byte) (ret *V, err error) {
 	return nil, ErrRawBytesUnrecignized
 }
 
+var dot = []byte{'.'}
+
 func (v *V) parseNumber() (err error) {
 	b := v.valueBytes
 
 	// if v.num == nil {
 	// 	v.num = &num{}
 	// }
 
-	if bytes.Contains(b, []byte(".")) {
+	if bytes.Contains(b, dot) {
 		v.num.floated = true
 		v.num.f64, err = parseFloat(b)
 		if err != nil {
@@ -259,7 +261,7 @@ func newFromNumber(b []byte) (ret *V, err error) {
 // }
 
 func newFromTrue(b []byte) (ret *V, err error) {
-	if len(b) != 4 || string(b) != "true" {
+	if len(b) != 4 || unsafeBtoS(b) != "true" {
 		return nil, ErrNotValidBoolValue
 	}
 	v := new(jsonparser.Boolean)
@@ -270,7 +272,7 @@ func newFromTrue(b []byte) (ret *V, err error) {
 }
 
 func newFromFalse(b []byte) (ret *V, err error) {
-	if len(b) != 5 || string(b) != "false" {
+	if len(b) != 5 || unsafeBtoS(b) != "false" {
 		return nil, ErrNotValidBoolValue
 	}
 	v := new(jsonparser.Boolean)
@@ -283,7 +285,7 @@ func newFromFalse(b []byte) (ret *V, err error) {
 func newFromBool(b []byte) (ret *V, err error) {
 	v := new(jsonparser.Boolean)
 
-	switch string(b) {
+	switch unsafeBtoS(b) {
 	case "true":
 		v.parsed = true
 		v.valueBytes = []byte{'t', 'r', 'u', 'e'}
@@ -300,7 +302,7 @@ func newFromBool(b []byte) (ret *V, err error) {
 }
 
 func newFromNull(b []byte) (ret *V, err error) {
-	if len(b) != 4 || string(b) != "null" {
+	if len(b) != 4 || unsafeBtoS(b) != "null" {
 		return nil, ErrNotValidBoolValue
 	}
 	v := new(jsonparser.Null)
@@ -682,7 +684,7 @@ func (v *V) String() string {
 	case jsonparser.Null:
 		return "null"
 	case jsonparser.Number:
-		return string(v.valueBytes)
+		return unsafeBtoS(v.valueBytes)
 	case jsonparser.String:
 		if !v.parsed {
 			var e error

unsafe.go

@@ -0,0 +1,7 @@
+package jsonvalue
+
+import "unsafe"
+
+func unsafeBtoS(b []byte) string {
+	return *(*string)(unsafe.Pointer(&b))
+}