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mirror of https://github.com/golang/go synced 2024-11-22 07:34:40 -07:00

json: Marshal, Unmarshal using new scanner

R=r
CC=golang-dev
https://golang.org/cl/953041
This commit is contained in:
Russ Cox 2010-04-21 16:40:53 -07:00
parent 214a55b06a
commit dba9d62bc2
11 changed files with 1570 additions and 1053 deletions

View File

@ -225,16 +225,13 @@ func expvarHandler(c *http.Conn, req *http.Request) {
}
func memstats() string {
var buf bytes.Buffer
json.MarshalIndent(&buf, &runtime.MemStats, " ")
s := buf.String()
return s[0 : len(s)-1] // chop final \n
b, _ := json.MarshalIndent(&runtime.MemStats, "", "\t")
return string(b)
}
func cmdline() string {
var buf bytes.Buffer
json.Marshal(&buf, os.Args)
return buf.String()
b, _ := json.Marshal(os.Args)
return string(b)
}
func init() {

View File

@ -61,7 +61,8 @@ func TestMapCounter(t *testing.T) {
// colours.String() should be '{"red":3, "blue":4}',
// though the order of red and blue could vary.
s := colours.String()
j, err := json.Decode(s)
var j interface{}
err := json.Unmarshal([]byte(s), &j)
if err != nil {
t.Errorf("colours.String() isn't valid JSON: %v", err)
}

View File

@ -7,10 +7,10 @@ include ../../Make.$(GOARCH)
TARG=json
GOFILES=\
decode.go\
encode.go\
error.go\
indent.go\
parse.go\
scanner.go\
struct.go\
include ../../Make.pkg

View File

@ -1,4 +1,4 @@
// Copyright 2009 The Go Authors. All rights reserved.
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
@ -10,96 +10,888 @@ package json
import (
"container/vector"
"os"
"reflect"
"runtime"
"strconv"
"strings"
"unicode"
"utf16"
"utf8"
)
// Decode a JSON string
// Decode parses the string s as a JSON-syntax string and returns the
// generic JSON object representation. The object representation is a tree
// of Go data types. The data return value may be one of float64, string,
// bool, nil, []interface{} or map[string]interface{}. The array and map
// elements may in turn contain any of the types listed above and so on.
// Unmarshal parses the JSON-encoded data and stores the result
// in the value pointed at by v.
//
// If Decode encounters a syntax error, it returns with err set to an
// instance of ParseError. See ParseError documentation for details.
func Decode(s string) (data interface{}, err os.Error) {
jb := newDecoder(nil, nil)
ok, errPos, errTok := Parse(s, jb)
if ok {
data = jb.Data()
// Unmarshal traverses the value v recursively.
// If an encountered value implements the Unmarshaler interface,
// Unmarshal calls its UnmarshalJSON method with a well-formed
// JSON encoding.
//
// Otherwise, Unmarshal uses the inverse of the encodings that
// Marshal uses, allocating maps, slices, and pointers as necessary,
// with the following additional rules:
//
// To unmarshal a JSON value into a nil interface value, the
// type stored in the interface value is one of:
//
// bool, for JSON booleans
// float64, for JSON numbers
// string, for JSON strings
// []interface{}, for JSON arrays
// map[string]interface{}, for JSON objects
// nil for JSON null
//
// If a JSON value is not appropriate for a given target type,
// or if a JSON number overflows the target type, Unmarshal
// skips that field and completes the unmarshalling as best it can.
// If no more serious errors are encountered, Unmarshal returns
// an UnmarshalTypeError describing the earliest such error.
//
func Unmarshal(data []byte, v interface{}) os.Error {
d := new(decodeState).init(data)
// Quick check for well-formedness.
// Avoids filling out half a data structure
// before discovering a JSON syntax error.
err := checkValid(data, &d.scan)
if err != nil {
return err
}
return d.unmarshal(v)
}
// Unmarshaler is the interface implemented by objects
// that can unmarshal a JSON description of themselves.
// The input can be assumed to be a valid JSON object
// encoding. UnmarshalJSON must copy the JSON data
// if it wishes to retain the data after returning.
type Unmarshaler interface {
UnmarshalJSON([]byte) os.Error
}
// An UnmarshalTypeError describes a JSON value that was
// not appropriate for a value of a specific Go type.
type UnmarshalTypeError struct {
Value string // description of JSON value - "bool", "array", "number -5"
Type reflect.Type // type of Go value it could not be assigned to
}
func (e *UnmarshalTypeError) String() string {
return "json: cannot unmarshal " + e.Value + " into Go value of type " + e.Type.String()
}
// An InvalidUnmarshalError describes an invalid argument passed to Unmarshal.
// (The argument to Unmarshal must be a non-nil pointer.)
type InvalidUnmarshalError struct {
Type reflect.Type
}
func (e *InvalidUnmarshalError) String() string {
if e.Type == nil {
return "json: Unmarshal(nil)"
}
if _, ok := e.Type.(*reflect.PtrType); !ok {
return "json: Unmarshal(non-pointer " + e.Type.String() + ")"
}
return "json: Unmarshal(nil " + e.Type.String() + ")"
}
func (d *decodeState) unmarshal(v interface{}) (err os.Error) {
defer func() {
if r := recover(); r != nil {
if _, ok := r.(runtime.Error); ok {
panic(r)
}
err = r.(os.Error)
}
}()
rv := reflect.NewValue(v)
pv, ok := rv.(*reflect.PtrValue)
if !ok || pv.IsNil() {
return &InvalidUnmarshalError{reflect.Typeof(v)}
}
d.scan.reset()
d.value(pv.Elem())
return d.savedError
}
// decodeState represents the state while decoding a JSON value.
type decodeState struct {
data []byte
off int // read offset in data
scan scanner
nextscan scanner // for calls to nextValue
savedError os.Error
}
// errPhase is used for errors that should not happen unless
// there is a bug in the JSON decoder or something is editing
// the data slice while the decoder executes.
var errPhase = os.NewError("JSON decoder out of sync - data changing underfoot?")
func (d *decodeState) init(data []byte) *decodeState {
d.data = data
d.off = 0
d.savedError = nil
return d
}
// error aborts the decoding by panicking with err.
func (d *decodeState) error(err os.Error) {
panic(err)
}
// saveError saves the first err it is called with,
// for reporting at the end of the unmarshal.
func (d *decodeState) saveError(err os.Error) {
if d.savedError == nil {
d.savedError = err
}
}
// next cuts off and returns the next full JSON value in d.data[d.off:].
// The next value is known to be an object or array, not a literal.
func (d *decodeState) next() []byte {
c := d.data[d.off]
item, rest, err := nextValue(d.data[d.off:], &d.nextscan)
if err != nil {
d.error(err)
}
d.off = len(d.data) - len(rest)
// Our scanner has seen the opening brace/bracket
// and thinks we're still in the middle of the object.
// invent a closing brace/bracket to get it out.
if c == '{' {
d.scan.step(&d.scan, '}')
} else {
err = &ParseError{Index: errPos, Token: errTok}
d.scan.step(&d.scan, ']')
}
return item
}
// scanWhile processes bytes in d.data[d.off:] until it
// receives a scan code not equal to op.
// It updates d.off and returns the new scan code.
func (d *decodeState) scanWhile(op int) int {
var newOp int
for {
if d.off >= len(d.data) {
newOp = d.scan.eof()
d.off = len(d.data) + 1 // mark processed EOF with len+1
} else {
c := int(d.data[d.off])
d.off++
newOp = d.scan.step(&d.scan, c)
}
if newOp != op {
break
}
}
return newOp
}
// value decodes a JSON value from d.data[d.off:] into the value.
// it updates d.off to point past the decoded value.
func (d *decodeState) value(v reflect.Value) {
if v == nil {
_, rest, err := nextValue(d.data[d.off:], &d.nextscan)
if err != nil {
d.error(err)
}
d.off = len(d.data) - len(rest)
// d.scan thinks we're still at the beginning of the item.
// Feed in an empty string - the shortest, simplest value -
// so that it knows we got to the end of the value.
if d.scan.step == stateRedo {
panic("redo")
}
d.scan.step(&d.scan, '"')
d.scan.step(&d.scan, '"')
return
}
switch op := d.scanWhile(scanSkipSpace); op {
default:
d.error(errPhase)
case scanBeginArray:
d.array(v)
case scanBeginObject:
d.object(v)
case scanBeginLiteral:
d.literal(v)
}
}
// indirect walks down v allocating pointers as needed,
// until it gets to a non-pointer.
// if it encounters an Unmarshaler, indirect stops and returns that.
// if wantptr is true, indirect stops at the last pointer.
func (d *decodeState) indirect(v reflect.Value, wantptr bool) (Unmarshaler, reflect.Value) {
for {
var isUnmarshaler bool
if v.Type().NumMethod() > 0 {
// Remember that this is an unmarshaler,
// but wait to return it until after allocating
// the pointer (if necessary).
_, isUnmarshaler = v.Interface().(Unmarshaler)
}
pv, ok := v.(*reflect.PtrValue)
if !ok {
break
}
_, isptrptr := pv.Elem().(*reflect.PtrValue)
if !isptrptr && wantptr && !isUnmarshaler {
return nil, pv
}
pv.PointTo(reflect.MakeZero(pv.Type().(*reflect.PtrType).Elem()))
if isUnmarshaler {
// Using v.Interface().(Unmarshaler)
// here means that we have to use a pointer
// as the struct field. We cannot use a value inside
// a pointer to a struct, because in that case
// v.Interface() is the value (x.f) not the pointer (&x.f).
// This is an unfortunate consequence of reflect.
// An alternative would be to look up the
// UnmarshalJSON method and return a FuncValue.
return v.Interface().(Unmarshaler), nil
}
v = pv.Elem()
}
return nil, v
}
// array consumes an array from d.data[d.off-1:], decoding into the value v.
// the first byte of the array ('[') has been read already.
func (d *decodeState) array(v reflect.Value) {
// Check for unmarshaler.
unmarshaler, pv := d.indirect(v, false)
if unmarshaler != nil {
d.off--
err := unmarshaler.UnmarshalJSON(d.next())
if err != nil {
d.error(err)
}
return
}
}
v = pv
type decoder struct {
// A value being constructed.
value interface{}
// Container entity to flush into. Can be either vector.Vector or
// map[string]interface{}.
container interface{}
// The index into the container interface. Either int or string.
index interface{}
}
// Decoding into nil interface? Switch to non-reflect code.
iv, ok := v.(*reflect.InterfaceValue)
if ok {
iv.Set(reflect.NewValue(d.arrayInterface()))
return
}
func newDecoder(container interface{}, key interface{}) *decoder {
return &decoder{container: container, index: key}
}
func (j *decoder) Int64(i int64) { j.value = float64(i) }
func (j *decoder) Uint64(i uint64) { j.value = float64(i) }
func (j *decoder) Float64(f float64) { j.value = float64(f) }
func (j *decoder) String(s string) { j.value = s }
func (j *decoder) Bool(b bool) { j.value = b }
func (j *decoder) Null() { j.value = nil }
func (j *decoder) Array() { j.value = new(vector.Vector) }
func (j *decoder) Map() { j.value = make(map[string]interface{}) }
func (j *decoder) Elem(i int) Builder {
v, ok := j.value.(*vector.Vector)
// Check type of target.
av, ok := v.(reflect.ArrayOrSliceValue)
if !ok {
v = new(vector.Vector)
j.value = v
d.saveError(&UnmarshalTypeError{"array", v.Type()})
}
sv, _ := v.(*reflect.SliceValue)
i := 0
for {
// Look ahead for ] - can only happen on first iteration.
op := d.scanWhile(scanSkipSpace)
if op == scanEndArray {
break
}
// Back up so d.value can have the byte we just read.
d.off--
d.scan.undo(op)
// Get element of array, growing if necessary.
if i >= av.Cap() && sv != nil {
newcap := sv.Cap() + sv.Cap()/2
if newcap < 4 {
newcap = 4
}
newv := reflect.MakeSlice(sv.Type().(*reflect.SliceType), sv.Len(), newcap)
reflect.ArrayCopy(newv, sv)
sv.Set(newv)
}
if i >= av.Len() && sv != nil {
// Must be slice; gave up on array during i >= av.Cap().
sv.SetLen(i + 1)
}
// Decode into element.
if i < av.Len() {
d.value(av.Elem(i))
} else {
// Ran out of fixed array: skip.
d.value(nil)
}
i++
// Next token must be , or ].
op = d.scanWhile(scanSkipSpace)
if op == scanEndArray {
break
}
if op != scanArrayValue {
d.error(errPhase)
}
}
if i < av.Len() {
if sv == nil {
// Array. Zero the rest.
z := reflect.MakeZero(av.Type().(*reflect.ArrayType).Elem())
for ; i < av.Len(); i++ {
av.Elem(i).SetValue(z)
}
} else {
sv.SetLen(i)
}
if v.Len() <= i {
v.Resize(i+1, (i+1)*2)
}
return newDecoder(v, i)
}
func (j *decoder) Key(s string) Builder {
m, ok := j.value.(map[string]interface{})
// matchName returns true if key should be written to a field named name.
func matchName(key, name string) bool {
return strings.ToLower(key) == strings.ToLower(name)
}
// object consumes an object from d.data[d.off-1:], decoding into the value v.
// the first byte of the object ('{') has been read already.
func (d *decodeState) object(v reflect.Value) {
// Check for unmarshaler.
unmarshaler, pv := d.indirect(v, false)
if unmarshaler != nil {
d.off--
err := unmarshaler.UnmarshalJSON(d.next())
if err != nil {
d.error(err)
}
return
}
v = pv
// Decoding into nil interface? Switch to non-reflect code.
iv, ok := v.(*reflect.InterfaceValue)
if ok {
iv.Set(reflect.NewValue(d.objectInterface()))
return
}
// Check type of target: struct or map[string]T
var (
mv *reflect.MapValue
sv *reflect.StructValue
)
switch v := v.(type) {
case *reflect.MapValue:
// map must have string type
t := v.Type().(*reflect.MapType)
if t.Key() != reflect.Typeof("") {
d.saveError(&UnmarshalTypeError{"object", v.Type()})
break
}
mv = v
if mv.IsNil() {
mv.SetValue(reflect.MakeMap(t))
}
case *reflect.StructValue:
sv = v
default:
d.saveError(&UnmarshalTypeError{"object", v.Type()})
}
if mv == nil && sv == nil {
d.off--
d.next() // skip over { } in input
return
}
for {
// Read opening " of string key or closing }.
op := d.scanWhile(scanSkipSpace)
if op == scanEndObject {
// closing } - can only happen on first iteration.
break
}
if op != scanBeginLiteral {
d.error(errPhase)
}
// Read string key.
start := d.off - 1
op = d.scanWhile(scanContinue)
item := d.data[start : d.off-1]
key, ok := unquote(item)
if !ok {
m = make(map[string]interface{})
j.value = m
d.error(errPhase)
}
return newDecoder(m, s)
}
func (j *decoder) Flush() {
switch c := j.container.(type) {
case *vector.Vector:
index := j.index.(int)
c.Set(index, j.Data())
case map[string]interface{}:
index := j.index.(string)
c[index] = j.Data()
// Figure out
var subv reflect.Value
if mv != nil {
subv = reflect.MakeZero(mv.Type().(*reflect.MapType).Elem())
} else {
for i := 0; i < sv.NumField(); i++ {
f := sv.Type().(*reflect.StructType).Field(i)
if f.Tag == key {
subv = sv.Field(i)
break
}
}
if subv == nil {
subv = sv.FieldByNameFunc(func(s string) bool { return matchName(key, s) })
}
}
// Read : before value.
if op == scanSkipSpace {
op = d.scanWhile(scanSkipSpace)
}
if op != scanObjectKey {
d.error(errPhase)
}
// Read value.
d.value(subv)
// Write value back to map;
// if using struct, subv points into struct already.
if mv != nil {
mv.SetElem(reflect.NewValue(key), subv)
}
// Next token must be , or }.
op = d.scanWhile(scanSkipSpace)
if op == scanEndObject {
break
}
if op != scanObjectValue {
d.error(errPhase)
}
}
}
// Get the value built by this builder.
func (j *decoder) Data() interface{} {
switch v := j.value.(type) {
case *vector.Vector:
return v.Data()
// literal consumes a literal from d.data[d.off-1:], decoding into the value v.
// The first byte of the literal has been read already
// (that's how the caller knows it's a literal).
func (d *decodeState) literal(v reflect.Value) {
// All bytes inside literal return scanContinue op code.
start := d.off - 1
op := d.scanWhile(scanContinue)
// Scan read one byte too far; back up.
d.off--
d.scan.undo(op)
item := d.data[start:d.off]
// Check for unmarshaler.
wantptr := item[0] == 'n' // null
unmarshaler, pv := d.indirect(v, wantptr)
if unmarshaler != nil {
err := unmarshaler.UnmarshalJSON(item)
if err != nil {
d.error(err)
}
return
}
v = pv
switch c := item[0]; c {
case 'n': // null
switch v.(type) {
default:
d.saveError(&UnmarshalTypeError{"null", v.Type()})
case *reflect.InterfaceValue, *reflect.PtrValue, *reflect.MapValue:
v.SetValue(nil)
}
case 't', 'f': // true, false
value := c == 't'
switch v := v.(type) {
default:
d.saveError(&UnmarshalTypeError{"bool", v.Type()})
case *reflect.BoolValue:
v.Set(value)
case *reflect.InterfaceValue:
v.Set(reflect.NewValue(value))
}
case '"': // string
s, ok := unquote(item)
if !ok {
d.error(errPhase)
}
switch v := v.(type) {
default:
d.saveError(&UnmarshalTypeError{"string", v.Type()})
case *reflect.StringValue:
v.Set(s)
case *reflect.InterfaceValue:
v.Set(reflect.NewValue(s))
}
default: // number
if c != '-' && (c < '0' || c > '9') {
d.error(errPhase)
}
s := string(item)
switch v := v.(type) {
default:
d.error(&UnmarshalTypeError{"number", v.Type()})
case *reflect.InterfaceValue:
n, err := strconv.Atof64(s)
if err != nil {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(reflect.NewValue(n))
case *reflect.IntValue:
n, err := strconv.Atoi(s)
if err != nil {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(n)
case *reflect.Int8Value:
n, err := strconv.Atoi(s)
if err != nil || int(int8(n)) != n {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(int8(n))
case *reflect.Int16Value:
n, err := strconv.Atoi(s)
if err != nil || int(int16(n)) != n {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(int16(n))
case *reflect.Int32Value:
n, err := strconv.Atoi(s)
if err != nil || int(int32(n)) != n {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(int32(n))
case *reflect.Int64Value:
n, err := strconv.Atoi64(s)
if err != nil {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(n)
case *reflect.UintValue:
n, err := strconv.Atoui(s)
if err != nil {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(n)
case *reflect.Uint8Value:
n, err := strconv.Atoui(s)
if err != nil || uint(uint8(n)) != n {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(uint8(n))
case *reflect.Uint16Value:
n, err := strconv.Atoui(s)
if err != nil || uint(uint16(n)) != n {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(uint16(n))
case *reflect.Uint32Value:
n, err := strconv.Atoui(s)
if err != nil || uint(uint32(n)) != n {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(uint32(n))
case *reflect.Uint64Value:
n, err := strconv.Atoui64(s)
if err != nil {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(n)
case *reflect.UintptrValue:
n, err := strconv.Atoui64(s)
if err != nil || uint64(uintptr(n)) != n {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(uintptr(n))
case *reflect.FloatValue:
n, err := strconv.Atof(s)
if err != nil {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(n)
case *reflect.Float32Value:
n, err := strconv.Atof32(s)
if err != nil {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(n)
case *reflect.Float64Value:
n, err := strconv.Atof64(s)
if err != nil {
d.saveError(&UnmarshalTypeError{"number " + s, v.Type()})
break
}
v.Set(n)
}
}
return j.value
}
// The xxxInterface routines build up a value to be stored
// in an empty interface. They are not strictly necessary,
// but they avoid the weight of reflection in this common case.
// valueInterface is like value but returns interface{}
func (d *decodeState) valueInterface() interface{} {
switch d.scanWhile(scanSkipSpace) {
default:
d.error(errPhase)
case scanBeginArray:
return d.arrayInterface()
case scanBeginObject:
return d.objectInterface()
case scanBeginLiteral:
return d.literalInterface()
}
panic("unreachable")
}
// arrayInterface is like array but returns []interface{}.
func (d *decodeState) arrayInterface() []interface{} {
var v vector.Vector
for {
// Look ahead for ] - can only happen on first iteration.
op := d.scanWhile(scanSkipSpace)
if op == scanEndArray {
break
}
// Back up so d.value can have the byte we just read.
d.off--
d.scan.undo(op)
v.Push(d.valueInterface())
// Next token must be , or ].
op = d.scanWhile(scanSkipSpace)
if op == scanEndArray {
break
}
if op != scanArrayValue {
d.error(errPhase)
}
}
return v
}
// objectInterface is like object but returns map[string]interface{}.
func (d *decodeState) objectInterface() map[string]interface{} {
m := make(map[string]interface{})
for {
// Read opening " of string key or closing }.
op := d.scanWhile(scanSkipSpace)
if op == scanEndObject {
// closing } - can only happen on first iteration.
break
}
if op != scanBeginLiteral {
d.error(errPhase)
}
// Read string key.
start := d.off - 1
op = d.scanWhile(scanContinue)
item := d.data[start : d.off-1]
key, ok := unquote(item)
if !ok {
d.error(errPhase)
}
// Read : before value.
if op == scanSkipSpace {
op = d.scanWhile(scanSkipSpace)
}
if op != scanObjectKey {
d.error(errPhase)
}
// Read value.
m[key] = d.valueInterface()
// Next token must be , or }.
op = d.scanWhile(scanSkipSpace)
if op == scanEndObject {
break
}
if op != scanObjectValue {
d.error(errPhase)
}
}
return m
}
// literalInterface is like literal but returns an interface value.
func (d *decodeState) literalInterface() interface{} {
// All bytes inside literal return scanContinue op code.
start := d.off - 1
op := d.scanWhile(scanContinue)
// Scan read one byte too far; back up.
d.off--
d.scan.undo(op)
item := d.data[start:d.off]
switch c := item[0]; c {
case 'n': // null
return nil
case 't', 'f': // true, false
return c == 't'
case '"': // string
s, ok := unquote(item)
if !ok {
d.error(errPhase)
}
return s
default: // number
if c != '-' && (c < '0' || c > '9') {
d.error(errPhase)
}
n, err := strconv.Atof64(string(item))
if err != nil {
d.saveError(&UnmarshalTypeError{"number " + string(item), reflect.Typeof(float64(0))})
}
return n
}
panic("unreachable")
}
// getu4 decodes \uXXXX from the beginning of s, returning the hex value,
// or it returns -1.
func getu4(s []byte) int {
if len(s) < 6 || s[0] != '\\' || s[1] != 'u' {
return -1
}
rune, err := strconv.Btoui64(string(s[2:6]), 16)
if err != nil {
return -1
}
return int(rune)
}
// unquote converts a quoted JSON string literal s into an actual string t.
// The rules are different than for Go, so cannot use strconv.Unquote.
func unquote(s []byte) (t string, ok bool) {
if len(s) < 2 || s[0] != '"' || s[len(s)-1] != '"' {
return
}
b := make([]byte, len(s)+2*utf8.UTFMax)
w := 0
for r := 1; r < len(s)-1; {
// Out of room? Can only happen if s is full of
// malformed UTF-8 and we're replacing each
// byte with RuneError.
if w >= len(b)-2*utf8.UTFMax {
nb := make([]byte, (len(b)+utf8.UTFMax)*2)
copy(nb, b[0:w])
b = nb
}
switch c := s[r]; {
case c == '\\':
r++
if r >= len(s)-1 {
return
}
switch s[r] {
default:
return
case '"', '\\', '/', '\'':
b[w] = s[r]
r++
w++
case 'b':
b[w] = '\b'
r++
w++
case 'f':
b[w] = '\f'
r++
w++
case 'n':
b[w] = '\n'
r++
w++
case 'r':
b[w] = '\r'
r++
w++
case 't':
b[w] = '\t'
r++
w++
case 'u':
r--
rune := getu4(s[r:])
if rune < 0 {
return
}
r += 6
if utf16.IsSurrogate(rune) {
rune1 := getu4(s[r:])
if dec := utf16.DecodeRune(rune, rune1); dec != unicode.ReplacementChar {
// A valid pair; consume.
r += 6
w += utf8.EncodeRune(dec, b[w:])
break
}
// Invalid surrogate; fall back to replacement rune.
rune = unicode.ReplacementChar
}
w += utf8.EncodeRune(rune, b[w:])
}
// Quote, control characters are invalid.
case c == '"', c < ' ':
return
// ASCII
case c < utf8.RuneSelf:
b[w] = c
r++
w++
// Coerce to well-formed UTF-8.
default:
rune, size := utf8.DecodeRune(s[r:])
r += size
w += utf8.EncodeRune(rune, b[w:])
}
}
return string(b[0:w]), true
}

View File

@ -1,133 +1,427 @@
// Copyright 2009 The Go Authors. All rights reserved.
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package json
import (
"container/vector"
"bytes"
"reflect"
"strings"
"testing"
)
func TestDecodeInt64(t *testing.T) {
nb := newDecoder(nil, nil)
nb.Int64(-15)
assertResult(t, nb.Data(), float64(-15))
type unmarshalTest struct {
in string
ptr interface{}
out interface{}
}
func TestDecodeUint64(t *testing.T) {
nb := newDecoder(nil, nil)
nb.Uint64(15)
assertResult(t, nb.Data(), float64(15))
var unmarshalTests = []unmarshalTest{
// basic types
unmarshalTest{`true`, new(bool), true},
unmarshalTest{`1`, new(int), 1},
unmarshalTest{`1.2`, new(float), 1.2},
unmarshalTest{`-5`, new(int16), int16(-5)},
unmarshalTest{`"a\u1234"`, new(string), "a\u1234"},
unmarshalTest{`"g-clef: \uD834\uDD1E"`, new(string), "g-clef: \U0001D11E"},
unmarshalTest{`"invalid: \uD834x\uDD1E"`, new(string), "invalid: \uFFFDx\uFFFD"},
unmarshalTest{"null", new(interface{}), nil},
// composite tests
unmarshalTest{allValueIndent, new(All), allValue},
unmarshalTest{allValueCompact, new(All), allValue},
unmarshalTest{allValueIndent, new(*All), &allValue},
unmarshalTest{allValueCompact, new(*All), &allValue},
unmarshalTest{pallValueIndent, new(All), pallValue},
unmarshalTest{pallValueCompact, new(All), pallValue},
unmarshalTest{pallValueIndent, new(*All), &pallValue},
unmarshalTest{pallValueCompact, new(*All), &pallValue},
}
func TestDecodeFloat64(t *testing.T) {
nb := newDecoder(nil, nil)
nb.Float64(3.14159)
assertResult(t, nb.Data(), float64(3.14159))
}
func TestMarshal(t *testing.T) {
b, err := Marshal(allValue)
if err != nil {
t.Fatalf("Marshal allValue: %v", err)
}
if string(b) != allValueCompact {
t.Errorf("Marshal allValueCompact")
diff(t, b, []byte(allValueCompact))
return
}
func TestDecodeString(t *testing.T) {
nb := newDecoder(nil, nil)
nb.String("Some string")
assertResult(t, nb.Data(), "Some string")
}
func TestDecodeBool(t *testing.T) {
nb := newDecoder(nil, nil)
nb.Bool(true)
assertResult(t, nb.Data(), true)
}
func TestDecodeNull(t *testing.T) {
nb := newDecoder(nil, nil)
nb.Null()
assertResult(t, nb.Data(), nil)
}
func TestDecodeEmptyArray(t *testing.T) {
nb := newDecoder(nil, nil)
nb.Array()
assertResult(t, nb.Data(), []interface{}{})
}
func TestDecodeEmptyMap(t *testing.T) {
nb := newDecoder(nil, nil)
nb.Map()
assertResult(t, nb.Data(), map[string]interface{}{})
}
func TestDecodeFlushElem(t *testing.T) {
testVec := new(vector.Vector).Resize(2, 2)
nb := newDecoder(testVec, 1)
nb.Float64(3.14159)
nb.Flush()
assertResult(t, testVec.Data(), []interface{}{nil, float64(3.14159)})
}
func TestDecodeFlushKey(t *testing.T) {
testMap := make(map[string]interface{})
nb := newDecoder(testMap, "key")
nb.Float64(3.14159)
nb.Flush()
assertResult(t, testMap, map[string]interface{}{"key": float64(3.14159)})
}
// Elem() and Key() are hard to test in isolation because all they do
// is create a new, properly initialized, decoder, and modify state of
// the underlying decoder. I'm testing them through already tested
// Array(), String(), and Flush().
func TestDecodeElem(t *testing.T) {
nb := newDecoder(nil, nil)
nb.Array()
var b Builder = nb.Elem(0)
b.String("0")
b.Flush()
assertResult(t, nb.Data(), []interface{}{"0"})
}
func TestDecodeKey(t *testing.T) {
nb := newDecoder(nil, nil)
nb.Map()
var b Builder = nb.Key("a")
b.String("0")
b.Flush()
assertResult(t, nb.Data(), map[string]interface{}{"a": "0"})
}
func assertResult(t *testing.T, results, expected interface{}) {
if !reflect.DeepEqual(results, expected) {
t.Fatalf("have %T(%#v) want %T(%#v)", results, results, expected, expected)
b, err = Marshal(pallValue)
if err != nil {
t.Fatalf("Marshal pallValue: %v", err)
}
if string(b) != pallValueCompact {
t.Errorf("Marshal pallValueCompact")
diff(t, b, []byte(pallValueCompact))
return
}
}
type decodeTest struct {
s string
r interface{}
}
var tests = []decodeTest{
decodeTest{`null`, nil},
decodeTest{`true`, true},
decodeTest{`false`, false},
decodeTest{`"abc"`, "abc"},
decodeTest{`123`, float64(123)},
decodeTest{`0.1`, float64(0.1)},
decodeTest{`1e-10`, float64(1e-10)},
decodeTest{`[]`, []interface{}{}},
decodeTest{`[1,2,3,4]`, []interface{}{float64(1), float64(2), float64(3), float64(4)}},
decodeTest{`[1,2,"abc",null,true,false]`, []interface{}{float64(1), float64(2), "abc", nil, true, false}},
decodeTest{`{}`, map[string]interface{}{}},
decodeTest{`{"a":1}`, map[string]interface{}{"a": float64(1)}},
decodeTest{`"q\u0302"`, "q\u0302"},
}
func TestDecode(t *testing.T) {
for _, test := range tests {
if val, err := Decode(test.s); err != nil || !reflect.DeepEqual(val, test.r) {
t.Errorf("Decode(%#q) = %v, %v want %v, nil", test.s, val, err, test.r)
func TestUnmarshal(t *testing.T) {
var scan scanner
for i, tt := range unmarshalTests {
in := []byte(tt.in)
if err := checkValid(in, &scan); err != nil {
t.Errorf("#%d: checkValid: %v", i, err)
continue
}
// v = new(right-type)
v := reflect.NewValue(tt.ptr).(*reflect.PtrValue)
v.PointTo(reflect.MakeZero(v.Type().(*reflect.PtrType).Elem()))
if err := Unmarshal([]byte(in), v.Interface()); err != nil {
t.Errorf("#%d: %v", i, err)
continue
}
if !reflect.DeepEqual(v.Elem().Interface(), tt.out) {
t.Errorf("#%d: mismatch\nhave: %#+v\nwant: %#+v", i, v.Elem().Interface(), tt.out)
data, _ := Marshal(v.Elem().Interface())
println(string(data))
data, _ = Marshal(tt.out)
println(string(data))
return
continue
}
}
}
func TestUnmarshalMarshal(t *testing.T) {
var v interface{}
if err := Unmarshal(jsonBig, &v); err != nil {
t.Fatalf("Unmarshal: %v", err)
}
b, err := Marshal(v)
if err != nil {
t.Fatalf("Marshal: %v", err)
}
if bytes.Compare(jsonBig, b) != 0 {
t.Errorf("Marshal jsonBig")
diff(t, b, jsonBig)
return
}
}
func noSpace(c int) int {
if isSpace(c) {
return -1
}
return c
}
type All struct {
Bool bool
Int int
Int8 int8
Int16 int16
Int32 int32
Int64 int64
Uint uint
Uint8 uint8
Uint16 uint16
Uint32 uint32
Uint64 uint64
Uintptr uintptr
Float float
Float32 float32
Float64 float64
Foo string "bar"
PBool *bool
PInt *int
PInt8 *int8
PInt16 *int16
PInt32 *int32
PInt64 *int64
PUint *uint
PUint8 *uint8
PUint16 *uint16
PUint32 *uint32
PUint64 *uint64
PUintptr *uintptr
PFloat *float
PFloat32 *float32
PFloat64 *float64
String string
PString *string
Map map[string]Small
MapP map[string]*Small
PMap *map[string]Small
PMapP *map[string]*Small
EmptyMap map[string]Small
NilMap map[string]Small
Slice []Small
SliceP []*Small
PSlice *[]Small
PSliceP *[]*Small
EmptySlice []Small
NilSlice []Small
StringSlice []string
ByteSlice []byte
Small Small
PSmall *Small
PPSmall **Small
Interface interface{}
PInterface *interface{}
}
type Small struct {
Tag string
}
var allValue = All{
Bool: true,
Int: 2,
Int8: 3,
Int16: 4,
Int32: 5,
Int64: 6,
Uint: 7,
Uint8: 8,
Uint16: 9,
Uint32: 10,
Uint64: 11,
Uintptr: 12,
Float: 13.1,
Float32: 14.1,
Float64: 15.1,
Foo: "foo",
String: "16",
Map: map[string]Small{
"17": Small{Tag: "tag17"},
"18": Small{Tag: "tag18"},
},
MapP: map[string]*Small{
"19": &Small{Tag: "tag19"},
"20": nil,
},
EmptyMap: map[string]Small{},
Slice: []Small{Small{Tag: "tag20"}, Small{Tag: "tag21"}},
SliceP: []*Small{&Small{Tag: "tag22"}, nil, &Small{Tag: "tag23"}},
EmptySlice: []Small{},
StringSlice: []string{"str24", "str25", "str26"},
ByteSlice: []byte{27, 28, 29},
Small: Small{Tag: "tag30"},
PSmall: &Small{Tag: "tag31"},
Interface: float64(5.2),
}
var pallValue = All{
PBool: &allValue.Bool,
PInt: &allValue.Int,
PInt8: &allValue.Int8,
PInt16: &allValue.Int16,
PInt32: &allValue.Int32,
PInt64: &allValue.Int64,
PUint: &allValue.Uint,
PUint8: &allValue.Uint8,
PUint16: &allValue.Uint16,
PUint32: &allValue.Uint32,
PUint64: &allValue.Uint64,
PUintptr: &allValue.Uintptr,
PFloat: &allValue.Float,
PFloat32: &allValue.Float32,
PFloat64: &allValue.Float64,
PString: &allValue.String,
PMap: &allValue.Map,
PMapP: &allValue.MapP,
PSlice: &allValue.Slice,
PSliceP: &allValue.SliceP,
PPSmall: &allValue.PSmall,
PInterface: &allValue.Interface,
}
var allValueIndent = `{
"bool": true,
"int": 2,
"int8": 3,
"int16": 4,
"int32": 5,
"int64": 6,
"uint": 7,
"uint8": 8,
"uint16": 9,
"uint32": 10,
"uint64": 11,
"uintptr": 12,
"float": 13.1,
"float32": 14.1,
"float64": 15.1,
"bar": "foo",
"pbool": null,
"pint": null,
"pint8": null,
"pint16": null,
"pint32": null,
"pint64": null,
"puint": null,
"puint8": null,
"puint16": null,
"puint32": null,
"puint64": null,
"puintptr": null,
"pfloat": null,
"pfloat32": null,
"pfloat64": null,
"string": "16",
"pstring": null,
"map": {
"17": {
"tag": "tag17"
},
"18": {
"tag": "tag18"
}
},
"mapp": {
"19": {
"tag": "tag19"
},
"20": null
},
"pmap": null,
"pmapp": null,
"emptymap": {},
"nilmap": null,
"slice": [
{
"tag": "tag20"
},
{
"tag": "tag21"
}
],
"slicep": [
{
"tag": "tag22"
},
null,
{
"tag": "tag23"
}
],
"pslice": null,
"pslicep": null,
"emptyslice": [],
"nilslice": [],
"stringslice": [
"str24",
"str25",
"str26"
],
"byteslice": [
27,
28,
29
],
"small": {
"tag": "tag30"
},
"psmall": {
"tag": "tag31"
},
"ppsmall": null,
"interface": 5.2,
"pinterface": null
}`
var allValueCompact = strings.Map(noSpace, allValueIndent)
var pallValueIndent = `{
"bool": false,
"int": 0,
"int8": 0,
"int16": 0,
"int32": 0,
"int64": 0,
"uint": 0,
"uint8": 0,
"uint16": 0,
"uint32": 0,
"uint64": 0,
"uintptr": 0,
"float": 0,
"float32": 0,
"float64": 0,
"bar": "",
"pbool": true,
"pint": 2,
"pint8": 3,
"pint16": 4,
"pint32": 5,
"pint64": 6,
"puint": 7,
"puint8": 8,
"puint16": 9,
"puint32": 10,
"puint64": 11,
"puintptr": 12,
"pfloat": 13.1,
"pfloat32": 14.1,
"pfloat64": 15.1,
"string": "",
"pstring": "16",
"map": null,
"mapp": null,
"pmap": {
"17": {
"tag": "tag17"
},
"18": {
"tag": "tag18"
}
},
"pmapp": {
"19": {
"tag": "tag19"
},
"20": null
},
"emptymap": null,
"nilmap": null,
"slice": [],
"slicep": [],
"pslice": [
{
"tag": "tag20"
},
{
"tag": "tag21"
}
],
"pslicep": [
{
"tag": "tag22"
},
null,
{
"tag": "tag23"
}
],
"emptyslice": [],
"nilslice": [],
"stringslice": [],
"byteslice": [],
"small": {
"tag": ""
},
"psmall": null,
"ppsmall": {
"tag": "tag31"
},
"interface": null,
"pinterface": 5.2
}`
var pallValueCompact = strings.Map(noSpace, pallValueIndent)

282
src/pkg/json/encode.go Normal file
View File

@ -0,0 +1,282 @@
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package json
import (
"os"
"bytes"
"reflect"
"runtime"
"sort"
"strconv"
"strings"
)
// Marshal returns the JSON encoding of v.
//
// Marshal traverses the value v recursively.
// If an encountered value implements the Marshaler interface,
// Marshal calls its MarshalJSON method to produce JSON.
//
// Otherwise, Marshal uses the following type-dependent default encodings:
//
// Boolean values encode as JSON booleans.
//
// Floating point and integer values encode as JSON numbers.
//
// String values encode as JSON strings, with each invalid UTF-8 sequence
// replaced by the encoding of the Unicode replacement character U+FFFD.
//
// Array and slice values encode as JSON arrays.
//
// Struct values encode as JSON objects. Each struct field becomes
// a member of the object. By default the object's key name is the
// struct field name converted to lower case. If the struct field
// has a tag, that tag will be used as the name instead.
//
// Map values encode as JSON objects.
// The map's key type must be string; the object keys are used directly
// as map keys.
//
// Pointer values encode as the value pointed at.
// A nil pointer encodes as the null JSON object.
//
// Interface values encode as the value contained in the interface.
// A nil interface value encodes as the null JSON object.
//
// Channel, complex, and function values cannot be encoded in JSON.
// Attempting to encode such a value causes Marshal to return
// an InvalidTypeError.
//
// JSON cannot represent cyclic data structures and Marshal does not
// handle them. Passing cyclic structures to Marshal will result in
// an infinite recursion.
//
func Marshal(v interface{}) ([]byte, os.Error) {
e := &encodeState{}
err := e.marshal(v)
if err != nil {
return nil, err
}
return e.Bytes(), nil
}
// MarshalIndent is like Marshal but applies Indent to format the output.
func MarshalIndent(v interface{}, prefix, indent string) ([]byte, os.Error) {
b, err := Marshal(v)
if err != nil {
return nil, err
}
var buf bytes.Buffer
err = Indent(&buf, b, prefix, indent)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
// Marshaler is the interface implemented by objects that
// can marshal themselves into valid JSON.
type Marshaler interface {
MarshalJSON() ([]byte, os.Error)
}
type UnsupportedTypeError struct {
Type reflect.Type
}
func (e *UnsupportedTypeError) String() string {
return "json: unsupported type: " + e.Type.String()
}
type MarshalerError struct {
Type reflect.Type
Error os.Error
}
func (e *MarshalerError) String() string {
return "json: error calling MarshalJSON for type " + e.Type.String() + ": " + e.Error.String()
}
type interfaceOrPtrValue interface {
IsNil() bool
Elem() reflect.Value
}
var hex = "0123456789abcdef"
// An encodeState encodes JSON into a bytes.Buffer.
type encodeState struct {
bytes.Buffer // accumulated output
}
func (e *encodeState) marshal(v interface{}) (err os.Error) {
defer func() {
if r := recover(); r != nil {
if _, ok := r.(runtime.Error); ok {
panic(r)
}
err = r.(os.Error)
}
}()
e.reflectValue(reflect.NewValue(v))
return nil
}
func (e *encodeState) error(err os.Error) {
panic(err)
}
func (e *encodeState) reflectValue(v reflect.Value) {
if v == nil {
e.WriteString("null")
return
}
if j, ok := v.Interface().(Marshaler); ok {
b, err := j.MarshalJSON()
if err == nil {
// copy JSON into buffer, checking validity.
err = Compact(&e.Buffer, b)
}
if err != nil {
e.error(&MarshalerError{v.Type(), err})
}
return
}
switch v := v.(type) {
case *reflect.BoolValue:
x := v.Get()
if x {
e.WriteString("true")
} else {
e.WriteString("false")
}
case *reflect.IntValue:
e.WriteString(strconv.Itoa(v.Get()))
case *reflect.Int8Value:
e.WriteString(strconv.Itoa(int(v.Get())))
case *reflect.Int16Value:
e.WriteString(strconv.Itoa(int(v.Get())))
case *reflect.Int32Value:
e.WriteString(strconv.Itoa(int(v.Get())))
case *reflect.Int64Value:
e.WriteString(strconv.Itoa64(v.Get()))
case *reflect.UintValue:
e.WriteString(strconv.Uitoa(v.Get()))
case *reflect.Uint8Value:
e.WriteString(strconv.Uitoa(uint(v.Get())))
case *reflect.Uint16Value:
e.WriteString(strconv.Uitoa(uint(v.Get())))
case *reflect.Uint32Value:
e.WriteString(strconv.Uitoa(uint(v.Get())))
case *reflect.Uint64Value:
e.WriteString(strconv.Uitoa64(v.Get()))
case *reflect.UintptrValue:
e.WriteString(strconv.Uitoa64(uint64(v.Get())))
case *reflect.FloatValue:
e.WriteString(strconv.Ftoa(v.Get(), 'g', -1))
case *reflect.Float32Value:
e.WriteString(strconv.Ftoa32(v.Get(), 'g', -1))
case *reflect.Float64Value:
e.WriteString(strconv.Ftoa64(v.Get(), 'g', -1))
case *reflect.StringValue:
e.string(v.Get())
case *reflect.StructValue:
e.WriteByte('{')
t := v.Type().(*reflect.StructType)
n := v.NumField()
for i := 0; i < n; i++ {
if i > 0 {
e.WriteByte(',')
}
f := t.Field(i)
if f.Tag != "" {
e.string(f.Tag)
} else {
e.string(strings.ToLower(f.Name))
}
e.WriteByte(':')
e.reflectValue(v.Field(i))
}
e.WriteByte('}')
case *reflect.MapValue:
if _, ok := v.Type().(*reflect.MapType).Key().(*reflect.StringType); !ok {
e.error(&UnsupportedTypeError{v.Type()})
}
if v.IsNil() {
e.WriteString("null")
break
}
e.WriteByte('{')
var sv stringValues = v.Keys()
sort.Sort(sv)
for i, k := range sv {
if i > 0 {
e.WriteByte(',')
}
e.string(k.(*reflect.StringValue).Get())
e.WriteByte(':')
e.reflectValue(v.Elem(k))
}
e.WriteByte('}')
case reflect.ArrayOrSliceValue:
e.WriteByte('[')
n := v.Len()
for i := 0; i < n; i++ {
if i > 0 {
e.WriteByte(',')
}
e.reflectValue(v.Elem(i))
}
e.WriteByte(']')
case interfaceOrPtrValue:
if v.IsNil() {
e.WriteString("null")
return
}
e.reflectValue(v.Elem())
default:
e.error(&UnsupportedTypeError{v.Type()})
}
return
}
// stringValues is a slice of reflect.Value holding *reflect.StringValue.
// It implements the methods to sort by string.
type stringValues []reflect.Value
func (sv stringValues) Len() int { return len(sv) }
func (sv stringValues) Swap(i, j int) { sv[i], sv[j] = sv[j], sv[i] }
func (sv stringValues) Less(i, j int) bool { return sv.get(i) < sv.get(j) }
func (sv stringValues) get(i int) string { return sv[i].(*reflect.StringValue).Get() }
func (e *encodeState) string(s string) {
e.WriteByte('"')
for _, c := range s {
switch {
case c < 0x20:
e.WriteString(`\u00`)
e.WriteByte(hex[c>>4])
e.WriteByte(hex[c&0xF])
case c == '\\' || c == '"':
e.WriteByte('\\')
fallthrough
default:
e.WriteRune(c)
}
}
e.WriteByte('"')
}

View File

@ -181,6 +181,10 @@ func (s *scanner) popParseState() {
}
}
func isSpace(c int) bool {
return c == ' ' || c == '\t' || c == '\r' || c == '\n'
}
// NOTE(rsc): The various instances of
//
// if c <= ' ' && (c == ' ' || c == '\t' || c == '\r' || c == '\n')
@ -590,7 +594,7 @@ func stateError(s *scanner, c int) int {
// error records an error and switches to the error state.
func (s *scanner) error(c int, context string) int {
s.step = stateError
s.err = SyntaxError("invalid character '" + quoteChar(c) + "' " + context)
s.err = SyntaxError("invalid character " + quoteChar(c) + " " + context)
return scanError
}

View File

@ -175,6 +175,7 @@ func diff(t *testing.T, a, b []byte) {
j = 0
}
t.Errorf("diverge at %d: «%s» vs «%s»", i, trim(a[j:]), trim(b[j:]))
return
}
}
}
@ -191,9 +192,11 @@ func trim(b []byte) []byte {
var jsonBig []byte
func init() {
var buf bytes.Buffer
Marshal(&buf, genValue(100000))
jsonBig = buf.Bytes()
b, err := Marshal(genValue(10000))
if err != nil {
panic(err)
}
jsonBig = b
}
func genValue(n int) interface{} {

View File

@ -1,481 +0,0 @@
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Marshalling and unmarshalling of
// JSON data into Go structs using reflection.
package json
import (
"bytes"
"fmt"
"io"
"os"
"reflect"
"strings"
)
type structBuilder struct {
val reflect.Value
// if map_ != nil, write val to map_[key] on each change
map_ *reflect.MapValue
key reflect.Value
}
var nobuilder *structBuilder
func isfloat(v reflect.Value) bool {
switch v.(type) {
case *reflect.FloatValue, *reflect.Float32Value, *reflect.Float64Value:
return true
}
return false
}
func setfloat(v reflect.Value, f float64) {
switch v := v.(type) {
case *reflect.FloatValue:
v.Set(float(f))
case *reflect.Float32Value:
v.Set(float32(f))
case *reflect.Float64Value:
v.Set(float64(f))
}
}
func setint(v reflect.Value, i int64) {
switch v := v.(type) {
case *reflect.IntValue:
v.Set(int(i))
case *reflect.Int8Value:
v.Set(int8(i))
case *reflect.Int16Value:
v.Set(int16(i))
case *reflect.Int32Value:
v.Set(int32(i))
case *reflect.Int64Value:
v.Set(int64(i))
case *reflect.UintValue:
v.Set(uint(i))
case *reflect.Uint8Value:
v.Set(uint8(i))
case *reflect.Uint16Value:
v.Set(uint16(i))
case *reflect.Uint32Value:
v.Set(uint32(i))
case *reflect.Uint64Value:
v.Set(uint64(i))
}
}
// If updating b.val is not enough to update the original,
// copy a changed b.val out to the original.
func (b *structBuilder) Flush() {
if b == nil {
return
}
if b.map_ != nil {
b.map_.SetElem(b.key, b.val)
}
}
func (b *structBuilder) Int64(i int64) {
if b == nil {
return
}
v := b.val
if isfloat(v) {
setfloat(v, float64(i))
} else {
setint(v, i)
}
}
func (b *structBuilder) Uint64(i uint64) {
if b == nil {
return
}
v := b.val
if isfloat(v) {
setfloat(v, float64(i))
} else {
setint(v, int64(i))
}
}
func (b *structBuilder) Float64(f float64) {
if b == nil {
return
}
v := b.val
if isfloat(v) {
setfloat(v, f)
} else {
setint(v, int64(f))
}
}
func (b *structBuilder) Null() {}
func (b *structBuilder) String(s string) {
if b == nil {
return
}
if v, ok := b.val.(*reflect.StringValue); ok {
v.Set(s)
}
}
func (b *structBuilder) Bool(tf bool) {
if b == nil {
return
}
if v, ok := b.val.(*reflect.BoolValue); ok {
v.Set(tf)
}
}
func (b *structBuilder) Array() {
if b == nil {
return
}
if v, ok := b.val.(*reflect.SliceValue); ok {
if v.IsNil() {
v.Set(reflect.MakeSlice(v.Type().(*reflect.SliceType), 0, 8))
}
}
}
func (b *structBuilder) Elem(i int) Builder {
if b == nil || i < 0 {
return nobuilder
}
switch v := b.val.(type) {
case *reflect.ArrayValue:
if i < v.Len() {
return &structBuilder{val: v.Elem(i)}
}
case *reflect.SliceValue:
if i >= v.Cap() {
n := v.Cap()
if n < 8 {
n = 8
}
for n <= i {
n *= 2
}
nv := reflect.MakeSlice(v.Type().(*reflect.SliceType), v.Len(), n)
reflect.ArrayCopy(nv, v)
v.Set(nv)
}
if v.Len() <= i && i < v.Cap() {
v.SetLen(i + 1)
}
if i < v.Len() {
return &structBuilder{val: v.Elem(i)}
}
}
return nobuilder
}
func (b *structBuilder) Map() {
if b == nil {
return
}
if v, ok := b.val.(*reflect.PtrValue); ok && v.IsNil() {
if v.IsNil() {
v.PointTo(reflect.MakeZero(v.Type().(*reflect.PtrType).Elem()))
b.Flush()
}
b.map_ = nil
b.val = v.Elem()
}
if v, ok := b.val.(*reflect.MapValue); ok && v.IsNil() {
v.Set(reflect.MakeMap(v.Type().(*reflect.MapType)))
}
}
func (b *structBuilder) Key(k string) Builder {
if b == nil {
return nobuilder
}
switch v := reflect.Indirect(b.val).(type) {
case *reflect.StructValue:
t := v.Type().(*reflect.StructType)
// Case-insensitive field lookup.
k = strings.ToLower(k)
for i := 0; i < t.NumField(); i++ {
if strings.ToLower(t.Field(i).Name) == k {
return &structBuilder{val: v.Field(i)}
}
}
case *reflect.MapValue:
t := v.Type().(*reflect.MapType)
if t.Key() != reflect.Typeof(k) {
break
}
key := reflect.NewValue(k)
elem := v.Elem(key)
if elem == nil {
v.SetElem(key, reflect.MakeZero(t.Elem()))
elem = v.Elem(key)
}
return &structBuilder{val: elem, map_: v, key: key}
}
return nobuilder
}
// Unmarshal parses the JSON syntax string s and fills in
// an arbitrary struct or slice pointed at by val.
// It uses the reflect package to assign to fields
// and arrays embedded in val. Well-formed data that does not fit
// into the struct is discarded.
//
// For example, given these definitions:
//
// type Email struct {
// Where string
// Addr string
// }
//
// type Result struct {
// Name string
// Phone string
// Email []Email
// }
//
// var r = Result{ "name", "phone", nil }
//
// unmarshalling the JSON syntax string
//
// {
// "email": [
// {
// "where": "home",
// "addr": "gre@example.com"
// },
// {
// "where": "work",
// "addr": "gre@work.com"
// }
// ],
// "name": "Grace R. Emlin",
// "address": "123 Main Street"
// }
//
// via Unmarshal(s, &r) is equivalent to assigning
//
// r = Result{
// "Grace R. Emlin", // name
// "phone", // no phone given
// []Email{
// Email{ "home", "gre@example.com" },
// Email{ "work", "gre@work.com" },
// },
// }
//
// Note that the field r.Phone has not been modified and
// that the JSON field "address" was discarded.
//
// Because Unmarshal uses the reflect package, it can only
// assign to upper case fields. Unmarshal uses a case-insensitive
// comparison to match JSON field names to struct field names.
//
// To unmarshal a top-level JSON array, pass in a pointer to an empty
// slice of the correct type.
//
// On success, Unmarshal returns with ok set to true.
// On a syntax error, it returns with ok set to false and errtok
// set to the offending token.
func Unmarshal(s string, val interface{}) (ok bool, errtok string) {
v := reflect.NewValue(val)
var b *structBuilder
// If val is a pointer to a slice, we append to the slice.
if ptr, ok := v.(*reflect.PtrValue); ok {
if slice, ok := ptr.Elem().(*reflect.SliceValue); ok {
b = &structBuilder{val: slice}
}
}
if b == nil {
b = &structBuilder{val: v}
}
ok, _, errtok = Parse(s, b)
if !ok {
return false, errtok
}
return true, ""
}
type MarshalError struct {
T reflect.Type
}
func (e *MarshalError) String() string {
return "json cannot encode value of type " + e.T.String()
}
type writeState struct {
bytes.Buffer
indent string
newlines bool
depth int
}
func (s *writeState) descend(bra byte) {
s.depth++
s.WriteByte(bra)
}
func (s *writeState) ascend(ket byte) {
s.depth--
s.writeIndent()
s.WriteByte(ket)
}
func (s *writeState) writeIndent() {
if s.newlines {
s.WriteByte('\n')
}
for i := 0; i < s.depth; i++ {
s.WriteString(s.indent)
}
}
func (s *writeState) writeArrayOrSlice(val reflect.ArrayOrSliceValue) {
s.descend('[')
for i := 0; i < val.Len(); i++ {
s.writeIndent()
s.writeValue(val.Elem(i))
if i < val.Len()-1 {
s.WriteByte(',')
}
}
s.ascend(']')
}
func (s *writeState) writeMap(val *reflect.MapValue) {
key := val.Type().(*reflect.MapType).Key()
if _, ok := key.(*reflect.StringType); !ok {
panic(&MarshalError{val.Type()})
}
s.descend('{')
keys := val.Keys()
for i := 0; i < len(keys); i++ {
s.writeIndent()
fmt.Fprintf(s, "%s:", Quote(keys[i].(*reflect.StringValue).Get()))
s.writeValue(val.Elem(keys[i]))
if i < len(keys)-1 {
s.WriteByte(',')
}
}
s.ascend('}')
}
func (s *writeState) writeStruct(val *reflect.StructValue) {
s.descend('{')
typ := val.Type().(*reflect.StructType)
for i := 0; i < val.NumField(); i++ {
s.writeIndent()
fmt.Fprintf(s, "%s:", Quote(typ.Field(i).Name))
s.writeValue(val.Field(i))
if i < val.NumField()-1 {
s.WriteByte(',')
}
}
s.ascend('}')
}
func (s *writeState) writeValue(val reflect.Value) {
if val == nil {
fmt.Fprint(s, "null")
return
}
switch v := val.(type) {
case *reflect.StringValue:
fmt.Fprint(s, Quote(v.Get()))
case *reflect.ArrayValue:
s.writeArrayOrSlice(v)
case *reflect.SliceValue:
s.writeArrayOrSlice(v)
case *reflect.MapValue:
s.writeMap(v)
case *reflect.StructValue:
s.writeStruct(v)
case *reflect.ChanValue,
*reflect.UnsafePointerValue,
*reflect.FuncValue:
panic(&MarshalError{val.Type()})
case *reflect.InterfaceValue:
if v.IsNil() {
fmt.Fprint(s, "null")
} else {
s.writeValue(v.Elem())
}
case *reflect.PtrValue:
if v.IsNil() {
fmt.Fprint(s, "null")
} else {
s.writeValue(v.Elem())
}
case *reflect.UintptrValue:
fmt.Fprintf(s, "%d", v.Get())
case *reflect.Uint64Value:
fmt.Fprintf(s, "%d", v.Get())
case *reflect.Uint32Value:
fmt.Fprintf(s, "%d", v.Get())
case *reflect.Uint16Value:
fmt.Fprintf(s, "%d", v.Get())
case *reflect.Uint8Value:
fmt.Fprintf(s, "%d", v.Get())
default:
value := val.(reflect.Value)
fmt.Fprintf(s, "%#v", value.Interface())
}
}
func (s *writeState) marshal(w io.Writer, val interface{}) (err os.Error) {
defer func() {
if e := recover(); e != nil {
err = e.(*MarshalError)
}
}()
s.writeValue(reflect.NewValue(val))
if s.newlines {
s.WriteByte('\n')
}
_, err = s.WriteTo(w)
return
}
// Marshal writes the JSON encoding of val to w.
//
// Due to limitations in JSON, val cannot include cyclic data
// structures, channels, functions, or maps.
func Marshal(w io.Writer, val interface{}) os.Error {
s := &writeState{indent: "", newlines: false, depth: 0}
return s.marshal(w, val)
}
// MarshalIndent writes the JSON encoding of val to w,
// indenting nested values using the indent string.
//
// Due to limitations in JSON, val cannot include cyclic data
// structures, channels, functions, or maps.
func MarshalIndent(w io.Writer, val interface{}, indent string) os.Error {
s := &writeState{indent: indent, newlines: true, depth: 0}
return s.marshal(w, val)
}

View File

@ -1,375 +0,0 @@
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package json
import (
"bytes"
"reflect"
"strconv"
"testing"
)
type myStruct struct {
T bool
F bool
S string
I8 int8
I16 int16
I32 int32
I64 int64
U8 uint8
U16 uint16
U32 uint32
U64 uint64
I int
U uint
Fl float
Fl32 float32
Fl64 float64
A []string
My *myStruct
Map map[string][]int
MapStruct map[string]myStruct
MapPtrStruct map[string]*myStruct
}
const encoded = `{"t":true,"f":false,"s":"abc","i8":1,"i16":2,"i32":3,"i64":4,` +
` "u8":5,"u16":6,"u32":7,"u64":8,` +
` "i":-9,"u":10,"bogusfield":"should be ignored",` +
` "fl":11.5,"fl32":12.25,"fl64":13.75,` +
` "a":["x","y","z"],"my":{"s":"subguy"},` +
`"map":{"k1":[1,2,3],"k2":[],"k3":[3,4]},` +
`"mapstruct":{"m1":{"u8":8}},` +
`"mapptrstruct":{"m1":{"u8":8}}}`
var decodedMap = map[string][]int{
"k1": []int{1, 2, 3},
"k2": []int{},
"k3": []int{3, 4},
}
var decodedMapStruct = map[string]myStruct{
"m1": myStruct{U8: 8},
}
var decodedMapPtrStruct = map[string]*myStruct{
"m1": &myStruct{U8: 8},
}
func check(t *testing.T, ok bool, name string, v interface{}) {
if !ok {
t.Errorf("%s = %v (BAD)", name, v)
} else {
t.Logf("%s = %v (good)", name, v)
}
}
const whiteSpaceEncoded = " \t{\n\"s\"\r:\"string\"\v}"
func TestUnmarshalWhitespace(t *testing.T) {
var m myStruct
ok, errtok := Unmarshal(whiteSpaceEncoded, &m)
if !ok {
t.Fatalf("Unmarshal failed near %s", errtok)
}
check(t, m.S == "string", "string", m.S)
}
func TestUnmarshal(t *testing.T) {
var m myStruct
m.F = true
ok, errtok := Unmarshal(encoded, &m)
if !ok {
t.Fatalf("Unmarshal failed near %s", errtok)
}
check(t, m.T == true, "t", m.T)
check(t, m.F == false, "f", m.F)
check(t, m.S == "abc", "s", m.S)
check(t, m.I8 == 1, "i8", m.I8)
check(t, m.I16 == 2, "i16", m.I16)
check(t, m.I32 == 3, "i32", m.I32)
check(t, m.I64 == 4, "i64", m.I64)
check(t, m.U8 == 5, "u8", m.U8)
check(t, m.U16 == 6, "u16", m.U16)
check(t, m.U32 == 7, "u32", m.U32)
check(t, m.U64 == 8, "u64", m.U64)
check(t, m.I == -9, "i", m.I)
check(t, m.U == 10, "u", m.U)
check(t, m.Fl == 11.5, "fl", m.Fl)
check(t, m.Fl32 == 12.25, "fl32", m.Fl32)
check(t, m.Fl64 == 13.75, "fl64", m.Fl64)
check(t, m.A != nil, "a", m.A)
if m.A != nil {
check(t, m.A[0] == "x", "a[0]", m.A[0])
check(t, m.A[1] == "y", "a[1]", m.A[1])
check(t, m.A[2] == "z", "a[2]", m.A[2])
}
check(t, m.My != nil, "my", m.My)
if m.My != nil {
check(t, m.My.S == "subguy", "my.s", m.My.S)
}
check(t, reflect.DeepEqual(m.Map, decodedMap), "map", m.Map)
check(t, reflect.DeepEqual(m.MapStruct, decodedMapStruct), "mapstruct", m.MapStruct)
check(t, reflect.DeepEqual(m.MapPtrStruct, decodedMapPtrStruct), "mapptrstruct", m.MapPtrStruct)
}
type Issue147Text struct {
Text string
}
type Issue147 struct {
Test []Issue147Text
}
const issue147Input = `{"test": [{"text":"0"},{"text":"1"},{"text":"2"},
{"text":"3"},{"text":"4"},{"text":"5"},
{"text":"6"},{"text":"7"},{"text":"8"},
{"text":"9"},{"text":"10"},{"text":"11"},
{"text":"12"},{"text":"13"},{"text":"14"},
{"text":"15"},{"text":"16"},{"text":"17"},
{"text":"18"},{"text":"19"},{"text":"20"},
{"text":"21"},{"text":"22"},{"text":"23"},
{"text":"24"},{"text":"25"},{"text":"26"},
{"text":"27"},{"text":"28"},{"text":"29"}]}`
func TestIssue147(t *testing.T) {
var timeline Issue147
Unmarshal(issue147Input, &timeline)
if len(timeline.Test) != 30 {
t.Errorf("wrong length: got %d want 30", len(timeline.Test))
}
for i, e := range timeline.Test {
if e.Text != strconv.Itoa(i) {
t.Errorf("index: %d got: %s want: %d", i, e.Text, i)
}
}
}
type Issue114 struct {
Text string
}
const issue114Input = `[{"text" : "0"}, {"text" : "1"}, {"text" : "2"}, {"text" : "3"}]`
func TestIssue114(t *testing.T) {
var items []Issue114
Unmarshal(issue114Input, &items)
if len(items) != 4 {
t.Errorf("wrong length: got %d want 4", len(items))
}
for i, e := range items {
if e.Text != strconv.Itoa(i) {
t.Errorf("index: %d got: %s want: %d", i, e.Text, i)
}
}
}
type marshalTest struct {
val interface{}
out string
}
type MTE string
type OneField struct {
a int
}
type ScalarWithString int
const (
AA ScalarWithString = iota
BB
CC
)
var scalarStrings = []string{"AA", "BB", "CC"}
func (x ScalarWithString) String() string { return scalarStrings[x] }
var marshalTests = []marshalTest{
// basic string
marshalTest{nil, "null"},
marshalTest{true, "true"},
marshalTest{false, "false"},
marshalTest{123, "123"},
marshalTest{0.1, "0.1"},
marshalTest{1e-10, "1e-10"},
marshalTest{"teststring", `"teststring"`},
marshalTest{[4]int{1, 2, 3, 4}, "[1,2,3,4]"},
marshalTest{[]int{1, 2, 3, 4}, "[1,2,3,4]"},
marshalTest{[]interface{}{nil}, "[null]"},
marshalTest{[][]int{[]int{1, 2}, []int{3, 4}}, "[[1,2],[3,4]]"},
marshalTest{map[string]string{"one": "one"}, `{"one":"one"}`},
marshalTest{map[string]int{"one": 1}, `{"one":1}`},
marshalTest{map[string]interface{}{"null": nil}, `{"null":null}`},
marshalTest{struct{}{}, "{}"},
marshalTest{struct{ a int }{1}, `{"a":1}`},
marshalTest{struct{ a interface{} }{nil}, `{"a":null}`},
marshalTest{struct {
a int
b string
}{1, "hello"},
`{"a":1,"b":"hello"}`,
},
marshalTest{map[string][]int{"3": []int{1, 2, 3}}, `{"3":[1,2,3]}`},
marshalTest{map[string]*MTE{"hi": nil}, `{"hi":null}`},
marshalTest{map[string]interface{}{"hi": 3}, `{"hi":3}`},
marshalTest{&OneField{3}, `{"a":3}`},
marshalTest{"\x05\x06", `"\u0005\u0006"`},
marshalTest{uintptr(50000), "50000"},
marshalTest{uint64(50000), "50000"},
marshalTest{uint32(50000), "50000"},
marshalTest{uint16(50000), "50000"},
marshalTest{uint8(50), "50"},
marshalTest{int64(50000), "50000"},
marshalTest{int32(50000), "50000"},
marshalTest{int16(10000), "10000"},
marshalTest{int8(50), "50"},
marshalTest{BB, "1"},
}
func TestMarshal(t *testing.T) {
for _, tt := range marshalTests {
var buf bytes.Buffer
err := Marshal(&buf, tt.val)
if err != nil {
t.Fatalf("Marshal(%T): %s", tt.val, err)
}
s := buf.String()
if s != tt.out {
t.Errorf("Marshal(%T) = %q, want %q\n", tt.val, s, tt.out)
}
}
}
type marshalIndentTest struct {
val interface{}
indent string
out string
}
const marshalIndentTest1 = `[
1,
2,
3,
4
]
`
const marshalIndentTest2 = `[
[
1,
2
],
[
3,
4
]
]
`
const marshalIndentTest3 = `[
[
1,
2
],
[
3,
4
]
]
`
const marshalIndentTest4 = `[
[
1,
2
],
[
3,
4
]
]
`
const marshalIndentTest5 = `{
"a":1,
"b":"hello"
}
`
const marshalIndentTest6 = `{
"3":[
1,
2,
3
]
}
`
var marshalIndentTests = []marshalIndentTest{
marshalIndentTest{[]int{1, 2, 3, 4}, " ", marshalIndentTest1},
marshalIndentTest{[][]int{[]int{1, 2}, []int{3, 4}}, "", marshalIndentTest2},
marshalIndentTest{[][]int{[]int{1, 2}, []int{3, 4}}, " ", marshalIndentTest3},
marshalIndentTest{[][]int{[]int{1, 2}, []int{3, 4}}, " ", marshalIndentTest4},
marshalIndentTest{struct {
a int
b string
}{1, "hello"},
" ",
marshalIndentTest5,
},
marshalIndentTest{map[string][]int{"3": []int{1, 2, 3}}, " ", marshalIndentTest6},
}
func TestMarshalIndent(t *testing.T) {
for _, tt := range marshalIndentTests {
var buf bytes.Buffer
err := MarshalIndent(&buf, tt.val, tt.indent)
if err != nil {
t.Fatalf("MarshalIndent(%v): %s", tt.val, err)
}
s := buf.String()
if s != tt.out {
t.Errorf("MarshalIndent(%v) = %q, want %q\n", tt.val, s, tt.out)
}
}
}
type marshalErrorTest struct {
val interface{}
error string
}
type ChanVal struct {
C chan int
}
var marshalErrorTests = []marshalErrorTest{
marshalErrorTest{map[chan int]string{make(chan int): "one"}, "json cannot encode value of type map[chan int] string"},
marshalErrorTest{make(chan int, 100), "json cannot encode value of type chan int"},
marshalErrorTest{new(ChanVal), "json cannot encode value of type chan int"},
}
func TestMarshalError(t *testing.T) {
for _, tt := range marshalErrorTests {
var buf bytes.Buffer
err := Marshal(&buf, tt.val)
if err == nil {
t.Fatalf("Marshal(%T): no error, want error %s", tt.val, tt.error)
}
if err.String() != tt.error {
t.Fatalf("Marshal(%T) = error %s, want error %s", tt.val, err, tt.error)
}
}
}

View File

@ -415,7 +415,7 @@ func testAll(t *testing.T, parseFunc func(*Test) (*Template, os.Error)) {
s.false = false
s.mp = make(map[string]string)
s.mp["mapkey"] = "Ahoy!"
s.json, _ = json.Decode("{\"maps\":[{\"a\":1,\"b\":2},{\"a\":3,\"b\":4}]}")
json.Unmarshal([]byte(`{"maps":[{"a":1,"b":2},{"a":3,"b":4}]}`), &s.json)
s.innermap.mp = make(map[string]int)
s.innermap.mp["innerkey"] = 55
s.stringmap = make(map[string]string)