use zero alloc read function in jsoniter

fieldpath/serialize-pe.go

@@ -22,6 +22,7 @@ import (
 	"io"
 	"strconv"
 	"strings"
+	"unsafe"
 
 	jsoniter "github.com/json-iterator/go"
 	"sigs.k8s.io/structured-merge-diff/value"
@@ -55,20 +56,18 @@ var (
 )
 
 // DeserializePathElement parses a serialized path element
-func DeserializePathElement(s string) (PathElement, error) {
-	b := []byte(s)
+func DeserializePathElement(b []byte) (PathElement, error) {
+	//b := []byte(s)
 	if len(b) < 2 {
 		return PathElement{}, errors.New("key must be 2 characters long:")
 	}
 	typeSep, b := b[:2], b[2:]
 	if typeSep[1] != peSepBytes[0] {
-		return PathElement{}, fmt.Errorf("missing colon: %v", s)
+		return PathElement{}, fmt.Errorf("missing colon: %s", b)
 	}
 	switch typeSep[0] {
 	case peFieldSepBytes[0]:
-		// Slice s rather than convert b, to save on
-		// allocations.
-		str := s[2:]
+		str := string(b)
 		return PathElement{
 			FieldName: &str,
 		}, nil
@@ -92,7 +91,7 @@ func DeserializePathElement(s string) (PathElement, error) {
 		}
 		return PathElement{Key: v.MapValue}, nil
 	case peIndexSepBytes[0]:
-		i, err := strconv.Atoi(s[2:])
+		i, err := strconv.Atoi(*(*string)(unsafe.Pointer(&b)))
 		if err != nil {
 			return PathElement{}, err
 		}

fieldpath/serialize-pe_test.go

@@ -38,7 +38,7 @@ func TestPathElementRoundTrip(t *testing.T) {
 
 	for _, test := range tests {
 		t.Run(test, func(t *testing.T) {
-			pe, err := DeserializePathElement(test)
+			pe, err := DeserializePathElement([]byte(test))
 			if err != nil {
 				t.Fatalf("Failed to create path element: %v", err)
 			}
@@ -54,7 +54,7 @@ func TestPathElementRoundTrip(t *testing.T) {
 }
 
 func TestPathElementIgnoreUnknown(t *testing.T) {
-	_, err := DeserializePathElement("r:Hello")
+	_, err := DeserializePathElement([]byte("r:Hello"))
 	if err != ErrUnknownPathElementType {
 		t.Fatalf("Unknown qualifiers must not return an invalid path element")
 	}
@@ -75,7 +75,7 @@ func TestDeserializePathElementError(t *testing.T) {
 
 	for _, test := range tests {
 		t.Run(test, func(t *testing.T) {
-			pe, err := DeserializePathElement(test)
+			pe, err := DeserializePathElement([]byte(test))
 			if err == nil {
 				t.Fatalf("Expected error, no error found. got: %#v, %s", pe, pe)
 			}

fieldpath/serialize.go

@@ -164,11 +164,11 @@ func (s *Set) emitContents_v1(includeSelf bool, stream *jsoniter.Stream, r *reus
 }
 
 // FromJSON clears s and reads a JSON formatted set structure.
-func (s *Set) FromJSON(r io.Reader) error {
-	// The iterator pool is completely useless for memory management, grrr.
-	iter := jsoniter.Parse(jsoniter.ConfigCompatibleWithStandardLibrary, r, 4096)
+func (s *Set) FromJSON(b []byte) error {
+	iter := readPool.BorrowIterator(b)
+	defer readPool.ReturnIterator(iter)
 
-	found, _ := readIter_v1(iter)
+	found, _, _ := readIter_v1(iter, nil)
 	if found == nil {
 		*s = Set{}
 	} else {
@@ -179,9 +179,9 @@ func (s *Set) FromJSON(r io.Reader) error {
 
 // returns true if this subtree is also (or only) a member of parent; s is nil
 // if there are no further children.
-func readIter_v1(iter *jsoniter.Iterator) (children *Set, isMember bool) {
-	iter.ReadMapCB(func(iter *jsoniter.Iterator, key string) bool {
-		if key == "." {
+func readIter_v1(iter *jsoniter.Iterator, buf []byte) (children *Set, isMember bool, bufout []byte) {
+	iter.ReadMapCBFieldAsBytes(buf, func(iter *jsoniter.Iterator, key []byte) bool {
+		if len(key) == 1 && key[0] == '.' {
 			isMember = true
 			iter.Skip()
 			return true
@@ -198,7 +198,8 @@ func readIter_v1(iter *jsoniter.Iterator) (children *Set, isMember bool) {
 			iter.Skip()
 			return true
 		}
-		grandchildren, childIsMember := readIter_v1(iter)
+		grandchildren, childIsMember, key := readIter_v1(iter, key)
+		buf = key
 		if childIsMember {
 			if children == nil {
 				children = &Set{}
@@ -233,5 +234,5 @@ func readIter_v1(iter *jsoniter.Iterator) (children *Set, isMember bool) {
 		isMember = true
 	}
 
-	return children, isMember
+	return children, isMember, buf
 }

fieldpath/serialize_test.go

@@ -17,9 +17,7 @@ limitations under the License.
 package fieldpath
 
 import (
-	"bytes"
 	"fmt"
-	"strings"
 	"testing"
 )
 
@@ -35,7 +33,7 @@ func TestSerializeV1(t *testing.T) {
 			continue
 		}
 		x2 := NewSet()
-		err = x2.FromJSON(bytes.NewReader(b))
+		err = x2.FromJSON(b)
 		if err != nil {
 			t.Errorf("Failed to deserialize %s: %v\n%#v", b, err, x)
 		}
@@ -54,7 +52,7 @@ func TestSerializeV1GoldenData(t *testing.T) {
 	for i, str := range examples {
 		t.Run(fmt.Sprintf("%v", i), func(t *testing.T) {
 			x := NewSet()
-			err := x.FromJSON(strings.NewReader(str))
+			err := x.FromJSON([]byte(str))
 			if err != nil {
 				t.Errorf("Failed to deserialize %s: %v\n%#v", str, err, x)
 			}
@@ -74,7 +72,7 @@ func TestDropUnknown(t *testing.T) {
 	input := `{"f:aaa":{},"r:aab":{}}`
 	expect := `{"f:aaa":{}}`
 	x := NewSet()
-	err := x.FromJSON(strings.NewReader(input))
+	err := x.FromJSON([]byte(input))
 	if err != nil {
 		t.Errorf("Failed to deserialize %s: %v\n%#v", input, err, x)
 	}

fieldpath/set_test.go

@@ -17,7 +17,6 @@ limitations under the License.
 package fieldpath
 
 import (
-	"bytes"
 	"fmt"
 	"math/rand"
 	"testing"
@@ -111,7 +110,7 @@ func BenchmarkFieldSet(b *testing.B) {
 			b.ReportAllocs()
 			s := NewSet()
 			for i := 0; i < b.N; i++ {
-				s.FromJSON(bytes.NewReader(serialized[rand.Intn(len(serialized))]))
+				s.FromJSON(serialized[rand.Intn(len(serialized))])
 			}
 		})
 

value/fastjson.go

@@ -87,7 +87,7 @@ func ReadJSONIter(iter *jsoniter.Iterator) (Value, error) {
 		return Value{ListValue: list}, iter.Error
 	case jsoniter.ObjectValue:
 		m := &Map{}
-		iter.ReadObjectCB(func(iter *jsoniter.Iterator, key string) bool {
+		iter.ReadMapCB(func(iter *jsoniter.Iterator, key string) bool {
 			v, err := ReadJSONIter(iter)
 			if err != nil {
 				iter.Error = err

value/unstructured_test.go

@@ -164,6 +164,7 @@ func TestToFromJSON(t *testing.T) {
 		`[]`,
 		`{}`,
 		`{"a":[null,1.2],"b":"something"}`,
+		//`{"a\"":[null,1.2],"a\u2029oeu":"something"}`,
 	}
 
 	for i, j := range js {
@@ -176,7 +177,7 @@ func TestToFromJSON(t *testing.T) {
 			if err != nil {
 				t.Fatalf("failed to marshal into json: %v", err)
 			}
-			if !reflect.DeepEqual(j, string(o)) {
+			if j != string(o) {
 				t.Fatalf("Failed to round-trip.\ninput: %#v\noutput: %#v", j, string(o))
 			}
 		})
@@ -189,8 +190,8 @@ func TestToFromJSON(t *testing.T) {
 			if err != nil {
 				t.Fatalf("failed to marshal into json: %v", err)
 			}
-			if !reflect.DeepEqual(j, string(o)) {
-				t.Fatalf("Failed to round-trip.\ninput: %#v\noutput: %#v", j, string(o))
+			if j != string(o) {
+				t.Fatalf("Failed to round-trip.\ninput:  %#v\noutput: %#v", j, string(o))
 			}
 		})
 	}