bsc/vendor/github.com/robertkrimen/otto/parser/lexer.go
Péter Szilágyi 289b30715d Godeps, vendor: convert dependency management to trash (#3198)
This commit converts the dependency management from Godeps to the vendor
folder, also switching the tool from godep to trash. Since the upstream tool
lacks a few features proposed via a few PRs, until those PRs are merged in
(if), use github.com/karalabe/trash.

You can update dependencies via trash --update.

All dependencies have been updated to their latest version.

Parts of the build system are reworked to drop old notions of Godeps and
invocation of the go vet command so that it doesn't run against the vendor
folder, as that will just blow up during vetting.

The conversion drops OpenCL (and hence GPU mining support) from ethash and our
codebase. The short reasoning is that there's noone to maintain and having
opencl libs in our deps messes up builds as go install ./... tries to build
them, failing with unsatisfied link errors for the C OpenCL deps.

golang.org/x/net/context is not vendored in. We expect it to be fetched by the
user (i.e. using go get). To keep ci.go builds reproducible the package is
"vendored" in build/_vendor.
2016-10-28 19:05:01 +02:00

867 lines
18 KiB
Go

package parser
import (
"bytes"
"errors"
"fmt"
"regexp"
"strconv"
"strings"
"unicode"
"unicode/utf8"
"github.com/robertkrimen/otto/ast"
"github.com/robertkrimen/otto/file"
"github.com/robertkrimen/otto/token"
)
type _chr struct {
value rune
width int
}
var matchIdentifier = regexp.MustCompile(`^[$_\p{L}][$_\p{L}\d}]*$`)
func isDecimalDigit(chr rune) bool {
return '0' <= chr && chr <= '9'
}
func digitValue(chr rune) int {
switch {
case '0' <= chr && chr <= '9':
return int(chr - '0')
case 'a' <= chr && chr <= 'f':
return int(chr - 'a' + 10)
case 'A' <= chr && chr <= 'F':
return int(chr - 'A' + 10)
}
return 16 // Larger than any legal digit value
}
func isDigit(chr rune, base int) bool {
return digitValue(chr) < base
}
func isIdentifierStart(chr rune) bool {
return chr == '$' || chr == '_' || chr == '\\' ||
'a' <= chr && chr <= 'z' || 'A' <= chr && chr <= 'Z' ||
chr >= utf8.RuneSelf && unicode.IsLetter(chr)
}
func isIdentifierPart(chr rune) bool {
return chr == '$' || chr == '_' || chr == '\\' ||
'a' <= chr && chr <= 'z' || 'A' <= chr && chr <= 'Z' ||
'0' <= chr && chr <= '9' ||
chr >= utf8.RuneSelf && (unicode.IsLetter(chr) || unicode.IsDigit(chr))
}
func (self *_parser) scanIdentifier() (string, error) {
offset := self.chrOffset
parse := false
for isIdentifierPart(self.chr) {
if self.chr == '\\' {
distance := self.chrOffset - offset
self.read()
if self.chr != 'u' {
return "", fmt.Errorf("Invalid identifier escape character: %c (%s)", self.chr, string(self.chr))
}
parse = true
var value rune
for j := 0; j < 4; j++ {
self.read()
decimal, ok := hex2decimal(byte(self.chr))
if !ok {
return "", fmt.Errorf("Invalid identifier escape character: %c (%s)", self.chr, string(self.chr))
}
value = value<<4 | decimal
}
if value == '\\' {
return "", fmt.Errorf("Invalid identifier escape value: %c (%s)", value, string(value))
} else if distance == 0 {
if !isIdentifierStart(value) {
return "", fmt.Errorf("Invalid identifier escape value: %c (%s)", value, string(value))
}
} else if distance > 0 {
if !isIdentifierPart(value) {
return "", fmt.Errorf("Invalid identifier escape value: %c (%s)", value, string(value))
}
}
}
self.read()
}
literal := string(self.str[offset:self.chrOffset])
if parse {
return parseStringLiteral(literal)
}
return literal, nil
}
// 7.2
func isLineWhiteSpace(chr rune) bool {
switch chr {
case '\u0009', '\u000b', '\u000c', '\u0020', '\u00a0', '\ufeff':
return true
case '\u000a', '\u000d', '\u2028', '\u2029':
return false
case '\u0085':
return false
}
return unicode.IsSpace(chr)
}
// 7.3
func isLineTerminator(chr rune) bool {
switch chr {
case '\u000a', '\u000d', '\u2028', '\u2029':
return true
}
return false
}
func (self *_parser) scan() (tkn token.Token, literal string, idx file.Idx) {
self.implicitSemicolon = false
for {
self.skipWhiteSpace()
idx = self.idxOf(self.chrOffset)
insertSemicolon := false
switch chr := self.chr; {
case isIdentifierStart(chr):
var err error
literal, err = self.scanIdentifier()
if err != nil {
tkn = token.ILLEGAL
break
}
if len(literal) > 1 {
// Keywords are longer than 1 character, avoid lookup otherwise
var strict bool
tkn, strict = token.IsKeyword(literal)
switch tkn {
case 0: // Not a keyword
if literal == "true" || literal == "false" {
self.insertSemicolon = true
tkn = token.BOOLEAN
return
} else if literal == "null" {
self.insertSemicolon = true
tkn = token.NULL
return
}
case token.KEYWORD:
tkn = token.KEYWORD
if strict {
// TODO If strict and in strict mode, then this is not a break
break
}
return
case
token.THIS,
token.BREAK,
token.THROW, // A newline after a throw is not allowed, but we need to detect it
token.RETURN,
token.CONTINUE,
token.DEBUGGER:
self.insertSemicolon = true
return
default:
return
}
}
self.insertSemicolon = true
tkn = token.IDENTIFIER
return
case '0' <= chr && chr <= '9':
self.insertSemicolon = true
tkn, literal = self.scanNumericLiteral(false)
return
default:
self.read()
switch chr {
case -1:
if self.insertSemicolon {
self.insertSemicolon = false
self.implicitSemicolon = true
}
tkn = token.EOF
case '\r', '\n', '\u2028', '\u2029':
self.insertSemicolon = false
self.implicitSemicolon = true
self.comments.AtLineBreak()
continue
case ':':
tkn = token.COLON
case '.':
if digitValue(self.chr) < 10 {
insertSemicolon = true
tkn, literal = self.scanNumericLiteral(true)
} else {
tkn = token.PERIOD
}
case ',':
tkn = token.COMMA
case ';':
tkn = token.SEMICOLON
case '(':
tkn = token.LEFT_PARENTHESIS
case ')':
tkn = token.RIGHT_PARENTHESIS
insertSemicolon = true
case '[':
tkn = token.LEFT_BRACKET
case ']':
tkn = token.RIGHT_BRACKET
insertSemicolon = true
case '{':
tkn = token.LEFT_BRACE
case '}':
tkn = token.RIGHT_BRACE
insertSemicolon = true
case '+':
tkn = self.switch3(token.PLUS, token.ADD_ASSIGN, '+', token.INCREMENT)
if tkn == token.INCREMENT {
insertSemicolon = true
}
case '-':
tkn = self.switch3(token.MINUS, token.SUBTRACT_ASSIGN, '-', token.DECREMENT)
if tkn == token.DECREMENT {
insertSemicolon = true
}
case '*':
tkn = self.switch2(token.MULTIPLY, token.MULTIPLY_ASSIGN)
case '/':
if self.chr == '/' {
if self.mode&StoreComments != 0 {
literal := string(self.readSingleLineComment())
self.comments.AddComment(ast.NewComment(literal, self.idx))
continue
}
self.skipSingleLineComment()
continue
} else if self.chr == '*' {
if self.mode&StoreComments != 0 {
literal = string(self.readMultiLineComment())
self.comments.AddComment(ast.NewComment(literal, self.idx))
continue
}
self.skipMultiLineComment()
continue
} else {
// Could be division, could be RegExp literal
tkn = self.switch2(token.SLASH, token.QUOTIENT_ASSIGN)
insertSemicolon = true
}
case '%':
tkn = self.switch2(token.REMAINDER, token.REMAINDER_ASSIGN)
case '^':
tkn = self.switch2(token.EXCLUSIVE_OR, token.EXCLUSIVE_OR_ASSIGN)
case '<':
tkn = self.switch4(token.LESS, token.LESS_OR_EQUAL, '<', token.SHIFT_LEFT, token.SHIFT_LEFT_ASSIGN)
case '>':
tkn = self.switch6(token.GREATER, token.GREATER_OR_EQUAL, '>', token.SHIFT_RIGHT, token.SHIFT_RIGHT_ASSIGN, '>', token.UNSIGNED_SHIFT_RIGHT, token.UNSIGNED_SHIFT_RIGHT_ASSIGN)
case '=':
tkn = self.switch2(token.ASSIGN, token.EQUAL)
if tkn == token.EQUAL && self.chr == '=' {
self.read()
tkn = token.STRICT_EQUAL
}
case '!':
tkn = self.switch2(token.NOT, token.NOT_EQUAL)
if tkn == token.NOT_EQUAL && self.chr == '=' {
self.read()
tkn = token.STRICT_NOT_EQUAL
}
case '&':
if self.chr == '^' {
self.read()
tkn = self.switch2(token.AND_NOT, token.AND_NOT_ASSIGN)
} else {
tkn = self.switch3(token.AND, token.AND_ASSIGN, '&', token.LOGICAL_AND)
}
case '|':
tkn = self.switch3(token.OR, token.OR_ASSIGN, '|', token.LOGICAL_OR)
case '~':
tkn = token.BITWISE_NOT
case '?':
tkn = token.QUESTION_MARK
case '"', '\'':
insertSemicolon = true
tkn = token.STRING
var err error
literal, err = self.scanString(self.chrOffset - 1)
if err != nil {
tkn = token.ILLEGAL
}
default:
self.errorUnexpected(idx, chr)
tkn = token.ILLEGAL
}
}
self.insertSemicolon = insertSemicolon
return
}
}
func (self *_parser) switch2(tkn0, tkn1 token.Token) token.Token {
if self.chr == '=' {
self.read()
return tkn1
}
return tkn0
}
func (self *_parser) switch3(tkn0, tkn1 token.Token, chr2 rune, tkn2 token.Token) token.Token {
if self.chr == '=' {
self.read()
return tkn1
}
if self.chr == chr2 {
self.read()
return tkn2
}
return tkn0
}
func (self *_parser) switch4(tkn0, tkn1 token.Token, chr2 rune, tkn2, tkn3 token.Token) token.Token {
if self.chr == '=' {
self.read()
return tkn1
}
if self.chr == chr2 {
self.read()
if self.chr == '=' {
self.read()
return tkn3
}
return tkn2
}
return tkn0
}
func (self *_parser) switch6(tkn0, tkn1 token.Token, chr2 rune, tkn2, tkn3 token.Token, chr3 rune, tkn4, tkn5 token.Token) token.Token {
if self.chr == '=' {
self.read()
return tkn1
}
if self.chr == chr2 {
self.read()
if self.chr == '=' {
self.read()
return tkn3
}
if self.chr == chr3 {
self.read()
if self.chr == '=' {
self.read()
return tkn5
}
return tkn4
}
return tkn2
}
return tkn0
}
func (self *_parser) chrAt(index int) _chr {
value, width := utf8.DecodeRuneInString(self.str[index:])
return _chr{
value: value,
width: width,
}
}
func (self *_parser) _peek() rune {
if self.offset+1 < self.length {
return rune(self.str[self.offset+1])
}
return -1
}
func (self *_parser) read() {
if self.offset < self.length {
self.chrOffset = self.offset
chr, width := rune(self.str[self.offset]), 1
if chr >= utf8.RuneSelf { // !ASCII
chr, width = utf8.DecodeRuneInString(self.str[self.offset:])
if chr == utf8.RuneError && width == 1 {
self.error(self.chrOffset, "Invalid UTF-8 character")
}
}
self.offset += width
self.chr = chr
} else {
self.chrOffset = self.length
self.chr = -1 // EOF
}
}
// This is here since the functions are so similar
func (self *_RegExp_parser) read() {
if self.offset < self.length {
self.chrOffset = self.offset
chr, width := rune(self.str[self.offset]), 1
if chr >= utf8.RuneSelf { // !ASCII
chr, width = utf8.DecodeRuneInString(self.str[self.offset:])
if chr == utf8.RuneError && width == 1 {
self.error(self.chrOffset, "Invalid UTF-8 character")
}
}
self.offset += width
self.chr = chr
} else {
self.chrOffset = self.length
self.chr = -1 // EOF
}
}
func (self *_parser) readSingleLineComment() (result []rune) {
for self.chr != -1 {
self.read()
if isLineTerminator(self.chr) {
return
}
result = append(result, self.chr)
}
// Get rid of the trailing -1
result = result[:len(result)-1]
return
}
func (self *_parser) readMultiLineComment() (result []rune) {
self.read()
for self.chr >= 0 {
chr := self.chr
self.read()
if chr == '*' && self.chr == '/' {
self.read()
return
}
result = append(result, chr)
}
self.errorUnexpected(0, self.chr)
return
}
func (self *_parser) skipSingleLineComment() {
for self.chr != -1 {
self.read()
if isLineTerminator(self.chr) {
return
}
}
}
func (self *_parser) skipMultiLineComment() {
self.read()
for self.chr >= 0 {
chr := self.chr
self.read()
if chr == '*' && self.chr == '/' {
self.read()
return
}
}
self.errorUnexpected(0, self.chr)
}
func (self *_parser) skipWhiteSpace() {
for {
switch self.chr {
case ' ', '\t', '\f', '\v', '\u00a0', '\ufeff':
self.read()
continue
case '\r':
if self._peek() == '\n' {
self.comments.AtLineBreak()
self.read()
}
fallthrough
case '\u2028', '\u2029', '\n':
if self.insertSemicolon {
return
}
self.comments.AtLineBreak()
self.read()
continue
}
if self.chr >= utf8.RuneSelf {
if unicode.IsSpace(self.chr) {
self.read()
continue
}
}
break
}
}
func (self *_parser) skipLineWhiteSpace() {
for isLineWhiteSpace(self.chr) {
self.read()
}
}
func (self *_parser) scanMantissa(base int) {
for digitValue(self.chr) < base {
self.read()
}
}
func (self *_parser) scanEscape(quote rune) {
var length, base uint32
switch self.chr {
//case '0', '1', '2', '3', '4', '5', '6', '7':
// Octal:
// length, base, limit = 3, 8, 255
case 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', '"', '\'', '0':
self.read()
return
case '\r', '\n', '\u2028', '\u2029':
self.scanNewline()
return
case 'x':
self.read()
length, base = 2, 16
case 'u':
self.read()
length, base = 4, 16
default:
self.read() // Always make progress
return
}
var value uint32
for ; length > 0 && self.chr != quote && self.chr >= 0; length-- {
digit := uint32(digitValue(self.chr))
if digit >= base {
break
}
value = value*base + digit
self.read()
}
}
func (self *_parser) scanString(offset int) (string, error) {
// " ' /
quote := rune(self.str[offset])
for self.chr != quote {
chr := self.chr
if chr == '\n' || chr == '\r' || chr == '\u2028' || chr == '\u2029' || chr < 0 {
goto newline
}
self.read()
if chr == '\\' {
if quote == '/' {
if self.chr == '\n' || self.chr == '\r' || self.chr == '\u2028' || self.chr == '\u2029' || self.chr < 0 {
goto newline
}
self.read()
} else {
self.scanEscape(quote)
}
} else if chr == '[' && quote == '/' {
// Allow a slash (/) in a bracket character class ([...])
// TODO Fix this, this is hacky...
quote = -1
} else if chr == ']' && quote == -1 {
quote = '/'
}
}
// " ' /
self.read()
return string(self.str[offset:self.chrOffset]), nil
newline:
self.scanNewline()
err := "String not terminated"
if quote == '/' {
err = "Invalid regular expression: missing /"
self.error(self.idxOf(offset), err)
}
return "", errors.New(err)
}
func (self *_parser) scanNewline() {
if self.chr == '\r' {
self.read()
if self.chr != '\n' {
return
}
}
self.read()
}
func hex2decimal(chr byte) (value rune, ok bool) {
{
chr := rune(chr)
switch {
case '0' <= chr && chr <= '9':
return chr - '0', true
case 'a' <= chr && chr <= 'f':
return chr - 'a' + 10, true
case 'A' <= chr && chr <= 'F':
return chr - 'A' + 10, true
}
return
}
}
func parseNumberLiteral(literal string) (value interface{}, err error) {
// TODO Is Uint okay? What about -MAX_UINT
value, err = strconv.ParseInt(literal, 0, 64)
if err == nil {
return
}
parseIntErr := err // Save this first error, just in case
value, err = strconv.ParseFloat(literal, 64)
if err == nil {
return
} else if err.(*strconv.NumError).Err == strconv.ErrRange {
// Infinity, etc.
return value, nil
}
err = parseIntErr
if err.(*strconv.NumError).Err == strconv.ErrRange {
if len(literal) > 2 && literal[0] == '0' && (literal[1] == 'X' || literal[1] == 'x') {
// Could just be a very large number (e.g. 0x8000000000000000)
var value float64
literal = literal[2:]
for _, chr := range literal {
digit := digitValue(chr)
if digit >= 16 {
goto error
}
value = value*16 + float64(digit)
}
return value, nil
}
}
error:
return nil, errors.New("Illegal numeric literal")
}
func parseStringLiteral(literal string) (string, error) {
// Best case scenario...
if literal == "" {
return "", nil
}
// Slightly less-best case scenario...
if !strings.ContainsRune(literal, '\\') {
return literal, nil
}
str := literal
buffer := bytes.NewBuffer(make([]byte, 0, 3*len(literal)/2))
for len(str) > 0 {
switch chr := str[0]; {
// We do not explicitly handle the case of the quote
// value, which can be: " ' /
// This assumes we're already passed a partially well-formed literal
case chr >= utf8.RuneSelf:
chr, size := utf8.DecodeRuneInString(str)
buffer.WriteRune(chr)
str = str[size:]
continue
case chr != '\\':
buffer.WriteByte(chr)
str = str[1:]
continue
}
if len(str) <= 1 {
panic("len(str) <= 1")
}
chr := str[1]
var value rune
if chr >= utf8.RuneSelf {
str = str[1:]
var size int
value, size = utf8.DecodeRuneInString(str)
str = str[size:] // \ + <character>
} else {
str = str[2:] // \<character>
switch chr {
case 'b':
value = '\b'
case 'f':
value = '\f'
case 'n':
value = '\n'
case 'r':
value = '\r'
case 't':
value = '\t'
case 'v':
value = '\v'
case 'x', 'u':
size := 0
switch chr {
case 'x':
size = 2
case 'u':
size = 4
}
if len(str) < size {
return "", fmt.Errorf("invalid escape: \\%s: len(%q) != %d", string(chr), str, size)
}
for j := 0; j < size; j++ {
decimal, ok := hex2decimal(str[j])
if !ok {
return "", fmt.Errorf("invalid escape: \\%s: %q", string(chr), str[:size])
}
value = value<<4 | decimal
}
str = str[size:]
if chr == 'x' {
break
}
if value > utf8.MaxRune {
panic("value > utf8.MaxRune")
}
case '0':
if len(str) == 0 || '0' > str[0] || str[0] > '7' {
value = 0
break
}
fallthrough
case '1', '2', '3', '4', '5', '6', '7':
// TODO strict
value = rune(chr) - '0'
j := 0
for ; j < 2; j++ {
if len(str) < j+1 {
break
}
chr := str[j]
if '0' > chr || chr > '7' {
break
}
decimal := rune(str[j]) - '0'
value = (value << 3) | decimal
}
str = str[j:]
case '\\':
value = '\\'
case '\'', '"':
value = rune(chr)
case '\r':
if len(str) > 0 {
if str[0] == '\n' {
str = str[1:]
}
}
fallthrough
case '\n':
continue
default:
value = rune(chr)
}
}
buffer.WriteRune(value)
}
return buffer.String(), nil
}
func (self *_parser) scanNumericLiteral(decimalPoint bool) (token.Token, string) {
offset := self.chrOffset
tkn := token.NUMBER
if decimalPoint {
offset--
self.scanMantissa(10)
goto exponent
}
if self.chr == '0' {
offset := self.chrOffset
self.read()
if self.chr == 'x' || self.chr == 'X' {
// Hexadecimal
self.read()
if isDigit(self.chr, 16) {
self.read()
} else {
return token.ILLEGAL, self.str[offset:self.chrOffset]
}
self.scanMantissa(16)
if self.chrOffset-offset <= 2 {
// Only "0x" or "0X"
self.error(0, "Illegal hexadecimal number")
}
goto hexadecimal
} else if self.chr == '.' {
// Float
goto float
} else {
// Octal, Float
if self.chr == 'e' || self.chr == 'E' {
goto exponent
}
self.scanMantissa(8)
if self.chr == '8' || self.chr == '9' {
return token.ILLEGAL, self.str[offset:self.chrOffset]
}
goto octal
}
}
self.scanMantissa(10)
float:
if self.chr == '.' {
self.read()
self.scanMantissa(10)
}
exponent:
if self.chr == 'e' || self.chr == 'E' {
self.read()
if self.chr == '-' || self.chr == '+' {
self.read()
}
if isDecimalDigit(self.chr) {
self.read()
self.scanMantissa(10)
} else {
return token.ILLEGAL, self.str[offset:self.chrOffset]
}
}
hexadecimal:
octal:
if isIdentifierStart(self.chr) || isDecimalDigit(self.chr) {
return token.ILLEGAL, self.str[offset:self.chrOffset]
}
return tkn, self.str[offset:self.chrOffset]
}