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-rw-r--r--vendor/github.com/d5/tengo/v2/stdlib/json/decode.go358
-rw-r--r--vendor/github.com/d5/tengo/v2/stdlib/json/encode.go146
-rw-r--r--vendor/github.com/d5/tengo/v2/stdlib/json/scanner.go562
3 files changed, 1066 insertions, 0 deletions
diff --git a/vendor/github.com/d5/tengo/v2/stdlib/json/decode.go b/vendor/github.com/d5/tengo/v2/stdlib/json/decode.go
new file mode 100644
index 00000000..6d468ef0
--- /dev/null
+++ b/vendor/github.com/d5/tengo/v2/stdlib/json/decode.go
@@ -0,0 +1,358 @@
+// A modified version of Go's JSON implementation.
+
+// 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 (
+ "strconv"
+ "unicode"
+ "unicode/utf16"
+ "unicode/utf8"
+
+ "github.com/d5/tengo/v2"
+)
+
+// Decode parses the JSON-encoded data and returns the result object.
+func Decode(data []byte) (tengo.Object, error) {
+ var d decodeState
+ err := checkValid(data, &d.scan)
+ if err != nil {
+ return nil, err
+ }
+ d.init(data)
+ d.scan.reset()
+ d.scanWhile(scanSkipSpace)
+ return d.value()
+}
+
+// decodeState represents the state while decoding a JSON value.
+type decodeState struct {
+ data []byte
+ off int // next read offset in data
+ opcode int // last read result
+ scan scanner
+}
+
+// readIndex returns the position of the last byte read.
+func (d *decodeState) readIndex() int {
+ return d.off - 1
+}
+
+const phasePanicMsg = "JSON decoder out of sync - data changing underfoot?"
+
+func (d *decodeState) init(data []byte) *decodeState {
+ d.data = data
+ d.off = 0
+ return d
+}
+
+// scanNext processes the byte at d.data[d.off].
+func (d *decodeState) scanNext() {
+ if d.off < len(d.data) {
+ d.opcode = d.scan.step(&d.scan, d.data[d.off])
+ d.off++
+ } else {
+ d.opcode = d.scan.eof()
+ d.off = len(d.data) + 1 // mark processed EOF with len+1
+ }
+}
+
+// scanWhile processes bytes in d.data[d.off:] until it
+// receives a scan code not equal to op.
+func (d *decodeState) scanWhile(op int) {
+ s, data, i := &d.scan, d.data, d.off
+ for i < len(data) {
+ newOp := s.step(s, data[i])
+ i++
+ if newOp != op {
+ d.opcode = newOp
+ d.off = i
+ return
+ }
+ }
+
+ d.off = len(data) + 1 // mark processed EOF with len+1
+ d.opcode = d.scan.eof()
+}
+
+func (d *decodeState) value() (tengo.Object, error) {
+ switch d.opcode {
+ default:
+ panic(phasePanicMsg)
+ case scanBeginArray:
+ o, err := d.array()
+ if err != nil {
+ return nil, err
+ }
+ d.scanNext()
+ return o, nil
+ case scanBeginObject:
+ o, err := d.object()
+ if err != nil {
+ return nil, err
+ }
+ d.scanNext()
+ return o, nil
+ case scanBeginLiteral:
+ return d.literal()
+ }
+}
+
+func (d *decodeState) array() (tengo.Object, error) {
+ var arr []tengo.Object
+ for {
+ // Look ahead for ] - can only happen on first iteration.
+ d.scanWhile(scanSkipSpace)
+ if d.opcode == scanEndArray {
+ break
+ }
+ o, err := d.value()
+ if err != nil {
+ return nil, err
+ }
+ arr = append(arr, o)
+
+ // Next token must be , or ].
+ if d.opcode == scanSkipSpace {
+ d.scanWhile(scanSkipSpace)
+ }
+ if d.opcode == scanEndArray {
+ break
+ }
+ if d.opcode != scanArrayValue {
+ panic(phasePanicMsg)
+ }
+ }
+ return &tengo.Array{Value: arr}, nil
+}
+
+func (d *decodeState) object() (tengo.Object, error) {
+ m := make(map[string]tengo.Object)
+ for {
+ // Read opening " of string key or closing }.
+ d.scanWhile(scanSkipSpace)
+ if d.opcode == scanEndObject {
+ // closing } - can only happen on first iteration.
+ break
+ }
+ if d.opcode != scanBeginLiteral {
+ panic(phasePanicMsg)
+ }
+
+ // Read string key.
+ start := d.readIndex()
+ d.scanWhile(scanContinue)
+ item := d.data[start:d.readIndex()]
+ key, ok := unquote(item)
+ if !ok {
+ panic(phasePanicMsg)
+ }
+
+ // Read : before value.
+ if d.opcode == scanSkipSpace {
+ d.scanWhile(scanSkipSpace)
+ }
+ if d.opcode != scanObjectKey {
+ panic(phasePanicMsg)
+ }
+ d.scanWhile(scanSkipSpace)
+
+ // Read value.
+ o, err := d.value()
+ if err != nil {
+ return nil, err
+ }
+
+ m[key] = o
+
+ // Next token must be , or }.
+ if d.opcode == scanSkipSpace {
+ d.scanWhile(scanSkipSpace)
+ }
+ if d.opcode == scanEndObject {
+ break
+ }
+ if d.opcode != scanObjectValue {
+ panic(phasePanicMsg)
+ }
+ }
+ return &tengo.Map{Value: m}, nil
+}
+
+func (d *decodeState) literal() (tengo.Object, error) {
+ // All bytes inside literal return scanContinue op code.
+ start := d.readIndex()
+ d.scanWhile(scanContinue)
+
+ item := d.data[start:d.readIndex()]
+
+ switch c := item[0]; c {
+ case 'n': // null
+ return tengo.UndefinedValue, nil
+
+ case 't', 'f': // true, false
+ if c == 't' {
+ return tengo.TrueValue, nil
+ }
+ return tengo.FalseValue, nil
+
+ case '"': // string
+ s, ok := unquote(item)
+ if !ok {
+ panic(phasePanicMsg)
+ }
+ return &tengo.String{Value: s}, nil
+
+ default: // number
+ if c != '-' && (c < '0' || c > '9') {
+ panic(phasePanicMsg)
+ }
+ n, _ := strconv.ParseFloat(string(item), 10)
+ return &tengo.Float{Value: n}, nil
+ }
+}
+
+// getu4 decodes \uXXXX from the beginning of s, returning the hex value,
+// or it returns -1.
+func getu4(s []byte) rune {
+ if len(s) < 6 || s[0] != '\\' || s[1] != 'u' {
+ return -1
+ }
+ var r rune
+ for _, c := range s[2:6] {
+ switch {
+ case '0' <= c && c <= '9':
+ c = c - '0'
+ case 'a' <= c && c <= 'f':
+ c = c - 'a' + 10
+ case 'A' <= c && c <= 'F':
+ c = c - 'A' + 10
+ default:
+ return -1
+ }
+ r = r*16 + rune(c)
+ }
+ return r
+}
+
+// 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) {
+ s, ok = unquoteBytes(s)
+ t = string(s)
+ return
+}
+
+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]
+
+ // Check for unusual characters. If there are none, then no unquoting is
+ // needed, so return a slice of the original bytes.
+ r := 0
+ for r < len(s) {
+ c := s[r]
+ if c == '\\' || c == '"' || c < ' ' {
+ break
+ }
+ if c < utf8.RuneSelf {
+ r++
+ continue
+ }
+ rr, size := utf8.DecodeRune(s[r:])
+ if rr == utf8.RuneError && size == 1 {
+ break
+ }
+ r += size
+ }
+ if r == len(s) {
+ return s, true
+ }
+
+ b := make([]byte, len(s)+2*utf8.UTFMax)
+ w := copy(b, s[0:r])
+ for r < len(s) {
+ // 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) {
+ 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--
+ rr := getu4(s[r:])
+ if rr < 0 {
+ return
+ }
+ r += 6
+ if utf16.IsSurrogate(rr) {
+ rr1 := getu4(s[r:])
+ dec := utf16.DecodeRune(rr, rr1)
+ if dec != unicode.ReplacementChar {
+ // A valid pair; consume.
+ r += 6
+ w += utf8.EncodeRune(b[w:], dec)
+ break
+ }
+ // Invalid surrogate; fall back to replacement rune.
+ rr = unicode.ReplacementChar
+ }
+ w += utf8.EncodeRune(b[w:], rr)
+ }
+ // 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:
+ rr, size := utf8.DecodeRune(s[r:])
+ r += size
+ w += utf8.EncodeRune(b[w:], rr)
+ }
+ }
+ return b[0:w], true
+}
diff --git a/vendor/github.com/d5/tengo/v2/stdlib/json/encode.go b/vendor/github.com/d5/tengo/v2/stdlib/json/encode.go
new file mode 100644
index 00000000..ab7ca6ff
--- /dev/null
+++ b/vendor/github.com/d5/tengo/v2/stdlib/json/encode.go
@@ -0,0 +1,146 @@
+// A modified version of Go's JSON implementation.
+
+// 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 (
+ "encoding/base64"
+ "errors"
+ "math"
+ "strconv"
+
+ "github.com/d5/tengo/v2"
+)
+
+// Encode returns the JSON encoding of the object.
+func Encode(o tengo.Object) ([]byte, error) {
+ var b []byte
+
+ switch o := o.(type) {
+ case *tengo.Array:
+ b = append(b, '[')
+ len1 := len(o.Value) - 1
+ for idx, elem := range o.Value {
+ eb, err := Encode(elem)
+ if err != nil {
+ return nil, err
+ }
+ b = append(b, eb...)
+ if idx < len1 {
+ b = append(b, ',')
+ }
+ }
+ b = append(b, ']')
+ case *tengo.ImmutableArray:
+ b = append(b, '[')
+ len1 := len(o.Value) - 1
+ for idx, elem := range o.Value {
+ eb, err := Encode(elem)
+ if err != nil {
+ return nil, err
+ }
+ b = append(b, eb...)
+ if idx < len1 {
+ b = append(b, ',')
+ }
+ }
+ b = append(b, ']')
+ case *tengo.Map:
+ b = append(b, '{')
+ len1 := len(o.Value) - 1
+ idx := 0
+ for key, value := range o.Value {
+ b = strconv.AppendQuote(b, key)
+ b = append(b, ':')
+ eb, err := Encode(value)
+ if err != nil {
+ return nil, err
+ }
+ b = append(b, eb...)
+ if idx < len1 {
+ b = append(b, ',')
+ }
+ idx++
+ }
+ b = append(b, '}')
+ case *tengo.ImmutableMap:
+ b = append(b, '{')
+ len1 := len(o.Value) - 1
+ idx := 0
+ for key, value := range o.Value {
+ b = strconv.AppendQuote(b, key)
+ b = append(b, ':')
+ eb, err := Encode(value)
+ if err != nil {
+ return nil, err
+ }
+ b = append(b, eb...)
+ if idx < len1 {
+ b = append(b, ',')
+ }
+ idx++
+ }
+ b = append(b, '}')
+ case *tengo.Bool:
+ if o.IsFalsy() {
+ b = strconv.AppendBool(b, false)
+ } else {
+ b = strconv.AppendBool(b, true)
+ }
+ case *tengo.Bytes:
+ b = append(b, '"')
+ encodedLen := base64.StdEncoding.EncodedLen(len(o.Value))
+ dst := make([]byte, encodedLen)
+ base64.StdEncoding.Encode(dst, o.Value)
+ b = append(b, dst...)
+ b = append(b, '"')
+ case *tengo.Char:
+ b = strconv.AppendInt(b, int64(o.Value), 10)
+ case *tengo.Float:
+ var y []byte
+
+ f := o.Value
+ if math.IsInf(f, 0) || math.IsNaN(f) {
+ return nil, errors.New("unsupported float value")
+ }
+
+ // Convert as if by ES6 number to string conversion.
+ // This matches most other JSON generators.
+ abs := math.Abs(f)
+ fmt := byte('f')
+ if abs != 0 {
+ if abs < 1e-6 || abs >= 1e21 {
+ fmt = 'e'
+ }
+ }
+ y = strconv.AppendFloat(y, f, fmt, -1, 64)
+ if fmt == 'e' {
+ // clean up e-09 to e-9
+ n := len(y)
+ if n >= 4 && y[n-4] == 'e' && y[n-3] == '-' && y[n-2] == '0' {
+ y[n-2] = y[n-1]
+ y = y[:n-1]
+ }
+ }
+
+ b = append(b, y...)
+ case *tengo.Int:
+ b = strconv.AppendInt(b, o.Value, 10)
+ case *tengo.String:
+ b = strconv.AppendQuote(b, o.Value)
+ case *tengo.Time:
+ y, err := o.Value.MarshalJSON()
+ if err != nil {
+ return nil, err
+ }
+ b = append(b, y...)
+ case *tengo.Undefined:
+ b = append(b, "null"...)
+ default:
+ // unknown type: ignore
+ }
+ return b, nil
+}
diff --git a/vendor/github.com/d5/tengo/v2/stdlib/json/scanner.go b/vendor/github.com/d5/tengo/v2/stdlib/json/scanner.go
new file mode 100644
index 00000000..aed15cf5
--- /dev/null
+++ b/vendor/github.com/d5/tengo/v2/stdlib/json/scanner.go
@@ -0,0 +1,562 @@
+// A modified version of Go's JSON implementation.
+
+// 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 "strconv"
+
+func checkValid(data []byte, scan *scanner) error {
+ scan.reset()
+ for _, c := range data {
+ scan.bytes++
+ if scan.step(scan, c) == scanError {
+ return scan.err
+ }
+ }
+ if scan.eof() == scanError {
+ return scan.err
+ }
+ return nil
+}
+
+// A SyntaxError is a description of a JSON syntax error.
+type SyntaxError struct {
+ msg string // description of error
+ Offset int64 // error occurred after reading Offset bytes
+}
+
+func (e *SyntaxError) Error() string { return e.msg }
+
+// A scanner is a JSON scanning state machine.
+// Callers call scan.reset() and then pass bytes in one at a time
+// by calling scan.step(&scan, c) for each byte.
+// The return value, referred to as an opcode, tells the
+// caller about significant parsing events like beginning
+// and ending literals, objects, and arrays, so that the
+// caller can follow along if it wishes.
+// The return value scanEnd indicates that a single top-level
+// JSON value has been completed, *before* the byte that
+// just got passed in. (The indication must be delayed in order
+// to recognize the end of numbers: is 123 a whole value or
+// the beginning of 12345e+6?).
+type scanner struct {
+ // The step is a func to be called to execute the next transition.
+ // Also tried using an integer constant and a single func
+ // with a switch, but using the func directly was 10% faster
+ // on a 64-bit Mac Mini, and it's nicer to read.
+ step func(*scanner, byte) int
+
+ // Reached end of top-level value.
+ endTop bool
+
+ // Stack of what we're in the middle of - array values, object keys, object values.
+ parseState []int
+
+ // Error that happened, if any.
+ err error
+
+ // total bytes consumed, updated by decoder.Decode
+ bytes int64
+}
+
+// These values are returned by the state transition functions
+// assigned to scanner.state and the method scanner.eof.
+// They give details about the current state of the scan that
+// callers might be interested to know about.
+// It is okay to ignore the return value of any particular
+// call to scanner.state: if one call returns scanError,
+// every subsequent call will return scanError too.
+const (
+ // Continue.
+ scanContinue = iota // uninteresting byte
+ scanBeginLiteral // end implied by next result != scanContinue
+ scanBeginObject // begin object
+ scanObjectKey // just finished object key (string)
+ scanObjectValue // just finished non-last object value
+ scanEndObject // end object (implies scanObjectValue if possible)
+ scanBeginArray // begin array
+ scanArrayValue // just finished array value
+ scanEndArray // end array (implies scanArrayValue if possible)
+ scanSkipSpace // space byte; can skip; known to be last "continue" result
+
+ // Stop.
+ scanEnd // top-level value ended *before* this byte; known to be first "stop" result
+ scanError // hit an error, scanner.err.
+)
+
+// These values are stored in the parseState stack.
+// They give the current state of a composite value
+// being scanned. If the parser is inside a nested value
+// the parseState describes the nested state, outermost at entry 0.
+const (
+ parseObjectKey = iota // parsing object key (before colon)
+ parseObjectValue // parsing object value (after colon)
+ parseArrayValue // parsing array value
+)
+
+// reset prepares the scanner for use.
+// It must be called before calling s.step.
+func (s *scanner) reset() {
+ s.step = stateBeginValue
+ s.parseState = s.parseState[0:0]
+ s.err = nil
+ s.endTop = false
+}
+
+// eof tells the scanner that the end of input has been reached.
+// It returns a scan status just as s.step does.
+func (s *scanner) eof() int {
+ if s.err != nil {
+ return scanError
+ }
+ if s.endTop {
+ return scanEnd
+ }
+ s.step(s, ' ')
+ if s.endTop {
+ return scanEnd
+ }
+ if s.err == nil {
+ s.err = &SyntaxError{"unexpected end of JSON input", s.bytes}
+ }
+ return scanError
+}
+
+// pushParseState pushes a new parse state p onto the parse stack.
+func (s *scanner) pushParseState(p int) {
+ s.parseState = append(s.parseState, p)
+}
+
+// popParseState pops a parse state (already obtained) off the stack
+// and updates s.step accordingly.
+func (s *scanner) popParseState() {
+ n := len(s.parseState) - 1
+ s.parseState = s.parseState[0:n]
+ if n == 0 {
+ s.step = stateEndTop
+ s.endTop = true
+ } else {
+ s.step = stateEndValue
+ }
+}
+
+func isSpace(c byte) bool {
+ return c == ' ' || c == '\t' || c == '\r' || c == '\n'
+}
+
+// stateBeginValueOrEmpty is the state after reading `[`.
+func stateBeginValueOrEmpty(s *scanner, c byte) int {
+ if c <= ' ' && isSpace(c) {
+ return scanSkipSpace
+ }
+ if c == ']' {
+ return stateEndValue(s, c)
+ }
+ return stateBeginValue(s, c)
+}
+
+// stateBeginValue is the state at the beginning of the input.
+func stateBeginValue(s *scanner, c byte) int {
+ if c <= ' ' && isSpace(c) {
+ return scanSkipSpace
+ }
+ switch c {
+ case '{':
+ s.step = stateBeginStringOrEmpty
+ s.pushParseState(parseObjectKey)
+ return scanBeginObject
+ case '[':
+ s.step = stateBeginValueOrEmpty
+ s.pushParseState(parseArrayValue)
+ return scanBeginArray
+ case '"':
+ s.step = stateInString
+ return scanBeginLiteral
+ case '-':
+ s.step = stateNeg
+ return scanBeginLiteral
+ case '0': // beginning of 0.123
+ s.step = state0
+ return scanBeginLiteral
+ case 't': // beginning of true
+ s.step = stateT
+ return scanBeginLiteral
+ case 'f': // beginning of false
+ s.step = stateF
+ return scanBeginLiteral
+ case 'n': // beginning of null
+ s.step = stateN
+ return scanBeginLiteral
+ }
+ if '1' <= c && c <= '9' { // beginning of 1234.5
+ s.step = state1
+ return scanBeginLiteral
+ }
+ return s.error(c, "looking for beginning of value")
+}
+
+// stateBeginStringOrEmpty is the state after reading `{`.
+func stateBeginStringOrEmpty(s *scanner, c byte) int {
+ if c <= ' ' && isSpace(c) {
+ return scanSkipSpace
+ }
+ if c == '}' {
+ n := len(s.parseState)
+ s.parseState[n-1] = parseObjectValue
+ return stateEndValue(s, c)
+ }
+ return stateBeginString(s, c)
+}
+
+// stateBeginString is the state after reading `{"key": value,`.
+func stateBeginString(s *scanner, c byte) int {
+ if c <= ' ' && isSpace(c) {
+ return scanSkipSpace
+ }
+ if c == '"' {
+ s.step = stateInString
+ return scanBeginLiteral
+ }
+ return s.error(c, "looking for beginning of object key string")
+}
+
+// stateEndValue is the state after completing a value,
+// such as after reading `{}` or `true` or `["x"`.
+func stateEndValue(s *scanner, c byte) int {
+ n := len(s.parseState)
+ if n == 0 {
+ // Completed top-level before the current byte.
+ s.step = stateEndTop
+ s.endTop = true
+ return stateEndTop(s, c)
+ }
+ if c <= ' ' && isSpace(c) {
+ s.step = stateEndValue
+ return scanSkipSpace
+ }
+ ps := s.parseState[n-1]
+ switch ps {
+ case parseObjectKey:
+ if c == ':' {
+ s.parseState[n-1] = parseObjectValue
+ s.step = stateBeginValue
+ return scanObjectKey
+ }
+ return s.error(c, "after object key")
+ case parseObjectValue:
+ if c == ',' {
+ s.parseState[n-1] = parseObjectKey
+ s.step = stateBeginString
+ return scanObjectValue
+ }
+ if c == '}' {
+ s.popParseState()
+ return scanEndObject
+ }
+ return s.error(c, "after object key:value pair")
+ case parseArrayValue:
+ if c == ',' {
+ s.step = stateBeginValue
+ return scanArrayValue
+ }
+ if c == ']' {
+ s.popParseState()
+ return scanEndArray
+ }
+ return s.error(c, "after array element")
+ }
+ return s.error(c, "")
+}
+
+// stateEndTop is the state after finishing the top-level value,
+// such as after reading `{}` or `[1,2,3]`.
+// Only space characters should be seen now.
+func stateEndTop(s *scanner, c byte) int {
+ if !isSpace(c) {
+ // Complain about non-space byte on next call.
+ s.error(c, "after top-level value")
+ }
+ return scanEnd
+}
+
+// stateInString is the state after reading `"`.
+func stateInString(s *scanner, c byte) int {
+ if c == '"' {
+ s.step = stateEndValue
+ return scanContinue
+ }
+ if c == '\\' {
+ s.step = stateInStringEsc
+ return scanContinue
+ }
+ if c < 0x20 {
+ return s.error(c, "in string literal")
+ }
+ return scanContinue
+}
+
+// stateInStringEsc is the state after reading `"\` during a quoted string.
+func stateInStringEsc(s *scanner, c byte) int {
+ switch c {
+ case 'b', 'f', 'n', 'r', 't', '\\', '/', '"':
+ s.step = stateInString
+ return scanContinue
+ case 'u':
+ s.step = stateInStringEscU
+ return scanContinue
+ }
+ return s.error(c, "in string escape code")
+}
+
+// stateInStringEscU is the state after reading `"\u` during a quoted string.
+func stateInStringEscU(s *scanner, c byte) int {
+ if '0' <= c && c <= '9' || 'a' <= c && c <= 'f' || 'A' <= c && c <= 'F' {
+ s.step = stateInStringEscU1
+ return scanContinue
+ }
+ // numbers
+ return s.error(c, "in \\u hexadecimal character escape")
+}
+
+// stateInStringEscU1 is the state after reading `"\u1` during a quoted string.
+func stateInStringEscU1(s *scanner, c byte) int {
+ if '0' <= c && c <= '9' || 'a' <= c && c <= 'f' || 'A' <= c && c <= 'F' {
+ s.step = stateInStringEscU12
+ return scanContinue
+ }
+ // numbers
+ return s.error(c, "in \\u hexadecimal character escape")
+}
+
+// stateInStringEscU12 is the state after reading `"\u12` during a quoted string.
+func stateInStringEscU12(s *scanner, c byte) int {
+ if '0' <= c && c <= '9' || 'a' <= c && c <= 'f' || 'A' <= c && c <= 'F' {
+ s.step = stateInStringEscU123
+ return scanContinue
+ }
+ // numbers
+ return s.error(c, "in \\u hexadecimal character escape")
+}
+
+// stateInStringEscU123 is the state after reading `"\u123` during a quoted string.
+func stateInStringEscU123(s *scanner, c byte) int {
+ if '0' <= c && c <= '9' || 'a' <= c && c <= 'f' || 'A' <= c && c <= 'F' {
+ s.step = stateInString
+ return scanContinue
+ }
+ // numbers
+ return s.error(c, "in \\u hexadecimal character escape")
+}
+
+// stateNeg is the state after reading `-` during a number.
+func stateNeg(s *scanner, c byte) int {
+ if c == '0' {
+ s.step = state0
+ return scanContinue
+ }
+ if '1' <= c && c <= '9' {
+ s.step = state1
+ return scanContinue
+ }
+ return s.error(c, "in numeric literal")
+}
+
+// state1 is the state after reading a non-zero integer during a number,
+// such as after reading `1` or `100` but not `0`.
+func state1(s *scanner, c byte) int {
+ if '0' <= c && c <= '9' {
+ s.step = state1
+ return scanContinue
+ }
+ return state0(s, c)
+}
+
+// state0 is the state after reading `0` during a number.
+func state0(s *scanner, c byte) int {
+ if c == '.' {
+ s.step = stateDot
+ return scanContinue
+ }
+ if c == 'e' || c == 'E' {
+ s.step = stateE
+ return scanContinue
+ }
+ return stateEndValue(s, c)
+}
+
+// stateDot is the state after reading the integer and decimal point in a number,
+// such as after reading `1.`.
+func stateDot(s *scanner, c byte) int {
+ if '0' <= c && c <= '9' {
+ s.step = stateDot0
+ return scanContinue
+ }
+ return s.error(c, "after decimal point in numeric literal")
+}
+
+// stateDot0 is the state after reading the integer, decimal point, and subsequent
+// digits of a number, such as after reading `3.14`.
+func stateDot0(s *scanner, c byte) int {
+ if '0' <= c && c <= '9' {
+ return scanContinue
+ }
+ if c == 'e' || c == 'E' {
+ s.step = stateE
+ return scanContinue
+ }
+ return stateEndValue(s, c)
+}
+
+// stateE is the state after reading the mantissa and e in a number,
+// such as after reading `314e` or `0.314e`.
+func stateE(s *scanner, c byte) int {
+ if c == '+' || c == '-' {
+ s.step = stateESign
+ return scanContinue
+ }
+ return stateESign(s, c)
+}
+
+// stateESign is the state after reading the mantissa, e, and sign in a number,
+// such as after reading `314e-` or `0.314e+`.
+func stateESign(s *scanner, c byte) int {
+ if '0' <= c && c <= '9' {
+ s.step = stateE0
+ return scanContinue
+ }
+ return s.error(c, "in exponent of numeric literal")
+}
+
+// stateE0 is the state after reading the mantissa, e, optional sign,
+// and at least one digit of the exponent in a number,
+// such as after reading `314e-2` or `0.314e+1` or `3.14e0`.
+func stateE0(s *scanner, c byte) int {
+ if '0' <= c && c <= '9' {
+ return scanContinue
+ }
+ return stateEndValue(s, c)
+}
+
+// stateT is the state after reading `t`.
+func stateT(s *scanner, c byte) int {
+ if c == 'r' {
+ s.step = stateTr
+ return scanContinue
+ }
+ return s.error(c, "in literal true (expecting 'r')")
+}
+
+// stateTr is the state after reading `tr`.
+func stateTr(s *scanner, c byte) int {
+ if c == 'u' {
+ s.step = stateTru
+ return scanContinue
+ }
+ return s.error(c, "in literal true (expecting 'u')")
+}
+
+// stateTru is the state after reading `tru`.
+func stateTru(s *scanner, c byte) int {
+ if c == 'e' {
+ s.step = stateEndValue
+ return scanContinue
+ }
+ return s.error(c, "in literal true (expecting 'e')")
+}
+
+// stateF is the state after reading `f`.
+func stateF(s *scanner, c byte) int {
+ if c == 'a' {
+ s.step = stateFa
+ return scanContinue
+ }
+ return s.error(c, "in literal false (expecting 'a')")
+}
+
+// stateFa is the state after reading `fa`.
+func stateFa(s *scanner, c byte) int {
+ if c == 'l' {
+ s.step = stateFal
+ return scanContinue
+ }
+ return s.error(c, "in literal false (expecting 'l')")
+}
+
+// stateFal is the state after reading `fal`.
+func stateFal(s *scanner, c byte) int {
+ if c == 's' {
+ s.step = stateFals
+ return scanContinue
+ }
+ return s.error(c, "in literal false (expecting 's')")
+}
+
+// stateFals is the state after reading `fals`.
+func stateFals(s *scanner, c byte) int {
+ if c == 'e' {
+ s.step = stateEndValue
+ return scanContinue
+ }
+ return s.error(c, "in literal false (expecting 'e')")
+}
+
+// stateN is the state after reading `n`.
+func stateN(s *scanner, c byte) int {
+ if c == 'u' {
+ s.step = stateNu
+ return scanContinue
+ }
+ return s.error(c, "in literal null (expecting 'u')")
+}
+
+// stateNu is the state after reading `nu`.
+func stateNu(s *scanner, c byte) int {
+ if c == 'l' {
+ s.step = stateNul
+ return scanContinue
+ }
+ return s.error(c, "in literal null (expecting 'l')")
+}
+
+// stateNul is the state after reading `nul`.
+func stateNul(s *scanner, c byte) int {
+ if c == 'l' {
+ s.step = stateEndValue
+ return scanContinue
+ }
+ return s.error(c, "in literal null (expecting 'l')")
+}
+
+// stateError is the state after reaching a syntax error,
+// such as after reading `[1}` or `5.1.2`.
+func stateError(_ *scanner, _ byte) int {
+ return scanError
+}
+
+// error records an error and switches to the error state.
+func (s *scanner) error(c byte, context string) int {
+ s.step = stateError
+ s.err = &SyntaxError{
+ msg: "invalid character " + quoteChar(c) + " " + context,
+ Offset: s.bytes,
+ }
+ return scanError
+}
+
+// quoteChar formats c as a quoted character literal
+func quoteChar(c byte) string {
+ // special cases - different from quoted strings
+ if c == '\'' {
+ return `'\''`
+ }
+ if c == '"' {
+ return `'"'`
+ }
+
+ // use quoted string with different quotation marks
+ s := strconv.Quote(string(c))
+ return "'" + s[1:len(s)-1] + "'"
+}