First commit

2025-07-27 17:28:38 +00:00 · 2017-11-19 21:10:04 -08:00 · 2017-11-19 21:10:04 -08:00 · 8ffb773f43
commit 8ffb773f43
2121 changed files with 1118910 additions and 0 deletions
--- a/vendor/github.com/tdewolff/parse/js/README.md
+++ b/vendor/github.com/tdewolff/parse/js/README.md
@ -0,0 +1,89 @@
+# JS [![GoDoc](http://godoc.org/github.com/tdewolff/parse/js?status.svg)](http://godoc.org/github.com/tdewolff/parse/js) [![GoCover](http://gocover.io/_badge/github.com/tdewolff/parse/js)](http://gocover.io/github.com/tdewolff/parse/js)
+
+This package is a JS lexer (ECMA-262, edition 6.0) written in [Go][1]. It follows the specification at [ECMAScript Language Specification](http://www.ecma-international.org/ecma-262/6.0/). The lexer takes an io.Reader and converts it into tokens until the EOF.
+
+## Installation
+Run the following command
+
+	go get github.com/tdewolff/parse/js
+
+or add the following import and run project with `go get`
+
+	import "github.com/tdewolff/parse/js"
+
+## Lexer
+### Usage
+The following initializes a new Lexer with io.Reader `r`:
+``` go
+l := js.NewLexer(r)
+```
+
+To tokenize until EOF an error, use:
+``` go
+for {
+	tt, text := l.Next()
+	switch tt {
+	case js.ErrorToken:
+		// error or EOF set in l.Err()
+		return
+	// ...
+	}
+}
+```
+
+All tokens (see [ECMAScript Language Specification](http://www.ecma-international.org/ecma-262/6.0/)):
+``` go
+ErrorToken          TokenType = iota // extra token when errors occur
+UnknownToken                         // extra token when no token can be matched
+WhitespaceToken                      // space \t \v \f
+LineTerminatorToken                  // \r \n \r\n
+CommentToken
+IdentifierToken // also: null true false
+PunctuatorToken /* { } ( ) [ ] . ; , < > <= >= == != === !==  + - * % ++ -- << >>
+   >>> & | ^ ! ~ && || ? : = += -= *= %= <<= >>= >>>= &= |= ^= / /= => */
+NumericToken
+StringToken
+RegexpToken
+TemplateToken
+```
+
+### Quirks
+Because the ECMAScript specification for `PunctuatorToken` (of which the `/` and `/=` symbols) and `RegexpToken` depends on a parser state to differentiate between the two, the lexer (to remain modular) uses different rules. It aims to correctly disambiguate contexts and returns `RegexpToken` or `PunctuatorToken` where appropriate with only few exceptions which don't make much sense in runtime and so don't happen in a real-world code: function literal division (`x = function y(){} / z`) and object literal division (`x = {y:1} / z`).
+
+Another interesting case introduced by ES2015 is `yield` operator in function generators vs `yield` as an identifier in regular functions. This was done for backward compatibility, but is very hard to disambiguate correctly on a lexer level without essentially implementing entire parsing spec as a state machine and hurting performance, code readability and maintainability, so, instead, `yield` is just always assumed to be an operator. In combination with above paragraph, this means that, for example, `yield /x/i` will be always parsed as `yield`-ing regular expression and not as `yield` identifier divided by `x` and then `i`. There is no evidence though that this pattern occurs in any popular libraries.
+
+### Examples
+``` go
+package main
+
+import (
+	"os"
+
+	"github.com/tdewolff/parse/js"
+)
+
+// Tokenize JS from stdin.
+func main() {
+	l := js.NewLexer(os.Stdin)
+	for {
+		tt, text := l.Next()
+		switch tt {
+		case js.ErrorToken:
+			if l.Err() != io.EOF {
+				fmt.Println("Error on line", l.Line(), ":", l.Err())
+			}
+			return
+		case js.IdentifierToken:
+			fmt.Println("Identifier", string(text))
+		case js.NumericToken:
+			fmt.Println("Numeric", string(text))
+		// ...
+		}
+	}
+}
+```
+
+## License
+Released under the [MIT license](https://github.com/tdewolff/parse/blob/master/LICENSE.md).
+
+[1]: http://golang.org/ "Go Language"
--- a/vendor/github.com/tdewolff/parse/js/hash.go
+++ b/vendor/github.com/tdewolff/parse/js/hash.go
@ -0,0 +1,156 @@
+package js
+
+// generated by hasher -file hash.go -type Hash; DO NOT EDIT, except for adding more constants to the list and rerun go generate
+
+// uses github.com/tdewolff/hasher
+//go:generate hasher -type=Hash -file=hash.go
+
+// Hash defines perfect hashes for a predefined list of strings
+type Hash uint32
+
+// Unique hash definitions to be used instead of strings
+const (
+	Break      Hash = 0x5    // break
+	Case       Hash = 0x3404 // case
+	Catch      Hash = 0xba05 // catch
+	Class      Hash = 0x505  // class
+	Const      Hash = 0x2c05 // const
+	Continue   Hash = 0x3e08 // continue
+	Debugger   Hash = 0x8408 // debugger
+	Default    Hash = 0xab07 // default
+	Delete     Hash = 0xcd06 // delete
+	Do         Hash = 0x4c02 // do
+	Else       Hash = 0x3704 // else
+	Enum       Hash = 0x3a04 // enum
+	Export     Hash = 0x1806 // export
+	Extends    Hash = 0x4507 // extends
+	False      Hash = 0x5a05 // false
+	Finally    Hash = 0x7a07 // finally
+	For        Hash = 0xc403 // for
+	Function   Hash = 0x4e08 // function
+	If         Hash = 0x5902 // if
+	Implements Hash = 0x5f0a // implements
+	Import     Hash = 0x6906 // import
+	In         Hash = 0x4202 // in
+	Instanceof Hash = 0x710a // instanceof
+	Interface  Hash = 0x8c09 // interface
+	Let        Hash = 0xcf03 // let
+	New        Hash = 0x1203 // new
+	Null       Hash = 0x5504 // null
+	Package    Hash = 0x9507 // package
+	Private    Hash = 0x9c07 // private
+	Protected  Hash = 0xa309 // protected
+	Public     Hash = 0xb506 // public
+	Return     Hash = 0xd06  // return
+	Static     Hash = 0x2f06 // static
+	Super      Hash = 0x905  // super
+	Switch     Hash = 0x2606 // switch
+	This       Hash = 0x2304 // this
+	Throw      Hash = 0x1d05 // throw
+	True       Hash = 0xb104 // true
+	Try        Hash = 0x6e03 // try
+	Typeof     Hash = 0xbf06 // typeof
+	Var        Hash = 0xc703 // var
+	Void       Hash = 0xca04 // void
+	While      Hash = 0x1405 // while
+	With       Hash = 0x2104 // with
+	Yield      Hash = 0x8005 // yield
+)
+
+// String returns the hash' name.
+func (i Hash) String() string {
+	start := uint32(i >> 8)
+	n := uint32(i & 0xff)
+	if start+n > uint32(len(_Hash_text)) {
+		return ""
+	}
+	return _Hash_text[start : start+n]
+}
+
+// ToHash returns the hash whose name is s. It returns zero if there is no
+// such hash. It is case sensitive.
+func ToHash(s []byte) Hash {
+	if len(s) == 0 || len(s) > _Hash_maxLen {
+		return 0
+	}
+	h := uint32(_Hash_hash0)
+	for i := 0; i < len(s); i++ {
+		h ^= uint32(s[i])
+		h *= 16777619
+	}
+	if i := _Hash_table[h&uint32(len(_Hash_table)-1)]; int(i&0xff) == len(s) {
+		t := _Hash_text[i>>8 : i>>8+i&0xff]
+		for i := 0; i < len(s); i++ {
+			if t[i] != s[i] {
+				goto NEXT
+			}
+		}
+		return i
+	}
+NEXT:
+	if i := _Hash_table[(h>>16)&uint32(len(_Hash_table)-1)]; int(i&0xff) == len(s) {
+		t := _Hash_text[i>>8 : i>>8+i&0xff]
+		for i := 0; i < len(s); i++ {
+			if t[i] != s[i] {
+				return 0
+			}
+		}
+		return i
+	}
+	return 0
+}
+
+const _Hash_hash0 = 0x9acb0442
+const _Hash_maxLen = 10
+const _Hash_text = "breakclassupereturnewhilexporthrowithiswitchconstaticaselsen" +
+	"umcontinuextendsdofunctionullifalseimplementsimportryinstanc" +
+	"eofinallyieldebuggerinterfacepackageprivateprotectedefaultru" +
+	"epublicatchtypeoforvarvoidelete"
+
+var _Hash_table = [1 << 6]Hash{
+	0x0:  0x2f06, // static
+	0x1:  0x9c07, // private
+	0x3:  0xb104, // true
+	0x6:  0x5a05, // false
+	0x7:  0x4c02, // do
+	0x9:  0x2c05, // const
+	0xa:  0x2606, // switch
+	0xb:  0x6e03, // try
+	0xc:  0x1203, // new
+	0xd:  0x4202, // in
+	0xf:  0x8005, // yield
+	0x10: 0x5f0a, // implements
+	0x11: 0xc403, // for
+	0x12: 0x505,  // class
+	0x13: 0x3a04, // enum
+	0x16: 0xc703, // var
+	0x17: 0x5902, // if
+	0x19: 0xcf03, // let
+	0x1a: 0x9507, // package
+	0x1b: 0xca04, // void
+	0x1c: 0xcd06, // delete
+	0x1f: 0x5504, // null
+	0x20: 0x1806, // export
+	0x21: 0xd06,  // return
+	0x23: 0x4507, // extends
+	0x25: 0x2304, // this
+	0x26: 0x905,  // super
+	0x27: 0x1405, // while
+	0x29: 0x5,    // break
+	0x2b: 0x3e08, // continue
+	0x2e: 0x3404, // case
+	0x2f: 0xab07, // default
+	0x31: 0x8408, // debugger
+	0x32: 0x1d05, // throw
+	0x33: 0xbf06, // typeof
+	0x34: 0x2104, // with
+	0x35: 0xba05, // catch
+	0x36: 0x4e08, // function
+	0x37: 0x710a, // instanceof
+	0x38: 0xa309, // protected
+	0x39: 0x8c09, // interface
+	0x3b: 0xb506, // public
+	0x3c: 0x3704, // else
+	0x3d: 0x7a07, // finally
+	0x3f: 0x6906, // import
+}
--- a/vendor/github.com/tdewolff/parse/js/hash_test.go
+++ b/vendor/github.com/tdewolff/parse/js/hash_test.go
@ -0,0 +1,18 @@
+package js // import "github.com/tdewolff/parse/js"
+
+import (
+	"testing"
+
+	"github.com/tdewolff/test"
+)
+
+func TestHashTable(t *testing.T) {
+	test.T(t, ToHash([]byte("break")), Break, "'break' must resolve to hash.Break")
+	test.T(t, ToHash([]byte("var")), Var, "'var' must resolve to hash.Var")
+	test.T(t, Break.String(), "break")
+	test.T(t, ToHash([]byte("")), Hash(0), "empty string must resolve to zero")
+	test.T(t, Hash(0xffffff).String(), "")
+	test.T(t, ToHash([]byte("breaks")), Hash(0), "'breaks' must resolve to zero")
+	test.T(t, ToHash([]byte("sdf")), Hash(0), "'sdf' must resolve to zero")
+	test.T(t, ToHash([]byte("uio")), Hash(0), "'uio' must resolve to zero")
+}
--- a/vendor/github.com/tdewolff/parse/js/lex.go
+++ b/vendor/github.com/tdewolff/parse/js/lex.go
@ -0,0 +1,650 @@
+// Package js is an ECMAScript5.1 lexer following the specifications at http://www.ecma-international.org/ecma-262/5.1/.
+package js // import "github.com/tdewolff/parse/js"
+
+import (
+	"io"
+	"strconv"
+	"unicode"
+
+	"github.com/tdewolff/parse/buffer"
+)
+
+var identifierStart = []*unicode.RangeTable{unicode.Lu, unicode.Ll, unicode.Lt, unicode.Lm, unicode.Lo, unicode.Nl, unicode.Other_ID_Start}
+var identifierContinue = []*unicode.RangeTable{unicode.Lu, unicode.Ll, unicode.Lt, unicode.Lm, unicode.Lo, unicode.Nl, unicode.Mn, unicode.Mc, unicode.Nd, unicode.Pc, unicode.Other_ID_Continue}
+
+////////////////////////////////////////////////////////////////
+
+// TokenType determines the type of token, eg. a number or a semicolon.
+type TokenType uint32
+
+// TokenType values.
+const (
+	ErrorToken          TokenType = iota // extra token when errors occur
+	UnknownToken                         // extra token when no token can be matched
+	WhitespaceToken                      // space \t \v \f
+	LineTerminatorToken                  // \r \n \r\n
+	CommentToken
+	IdentifierToken
+	PunctuatorToken /* { } ( ) [ ] . ; , < > <= >= == != === !==  + - * % ++ -- << >>
+	   >>> & | ^ ! ~ && || ? : = += -= *= %= <<= >>= >>>= &= |= ^= / /= >= */
+	NumericToken
+	StringToken
+	RegexpToken
+	TemplateToken
+)
+
+// TokenState determines a state in which next token should be read
+type TokenState uint32
+
+// TokenState values
+const (
+	ExprState TokenState = iota
+	StmtParensState
+	SubscriptState
+	PropNameState
+)
+
+// ParsingContext determines the context in which following token should be parsed.
+// This affects parsing regular expressions and template literals.
+type ParsingContext uint32
+
+// ParsingContext values
+const (
+	GlobalContext ParsingContext = iota
+	StmtParensContext
+	ExprParensContext
+	BracesContext
+	TemplateContext
+)
+
+// String returns the string representation of a TokenType.
+func (tt TokenType) String() string {
+	switch tt {
+	case ErrorToken:
+		return "Error"
+	case UnknownToken:
+		return "Unknown"
+	case WhitespaceToken:
+		return "Whitespace"
+	case LineTerminatorToken:
+		return "LineTerminator"
+	case CommentToken:
+		return "Comment"
+	case IdentifierToken:
+		return "Identifier"
+	case PunctuatorToken:
+		return "Punctuator"
+	case NumericToken:
+		return "Numeric"
+	case StringToken:
+		return "String"
+	case RegexpToken:
+		return "Regexp"
+	case TemplateToken:
+		return "Template"
+	}
+	return "Invalid(" + strconv.Itoa(int(tt)) + ")"
+}
+
+////////////////////////////////////////////////////////////////
+
+// Lexer is the state for the lexer.
+type Lexer struct {
+	r         *buffer.Lexer
+	stack     []ParsingContext
+	state     TokenState
+	emptyLine bool
+}
+
+// NewLexer returns a new Lexer for a given io.Reader.
+func NewLexer(r io.Reader) *Lexer {
+	return &Lexer{
+		r:         buffer.NewLexer(r),
+		stack:     make([]ParsingContext, 0, 16),
+		state:     ExprState,
+		emptyLine: true,
+	}
+}
+
+func (l *Lexer) enterContext(context ParsingContext) {
+	l.stack = append(l.stack, context)
+}
+
+func (l *Lexer) leaveContext() ParsingContext {
+	ctx := GlobalContext
+	if last := len(l.stack) - 1; last >= 0 {
+		ctx, l.stack = l.stack[last], l.stack[:last]
+	}
+	return ctx
+}
+
+// Err returns the error encountered during lexing, this is often io.EOF but also other errors can be returned.
+func (l *Lexer) Err() error {
+	return l.r.Err()
+}
+
+// Restore restores the NULL byte at the end of the buffer.
+func (l *Lexer) Restore() {
+	l.r.Restore()
+}
+
+// Next returns the next Token. It returns ErrorToken when an error was encountered. Using Err() one can retrieve the error message.
+func (l *Lexer) Next() (TokenType, []byte) {
+	tt := UnknownToken
+	c := l.r.Peek(0)
+	switch c {
+	case '(':
+		if l.state == StmtParensState {
+			l.enterContext(StmtParensContext)
+		} else {
+			l.enterContext(ExprParensContext)
+		}
+		l.state = ExprState
+		l.r.Move(1)
+		tt = PunctuatorToken
+	case ')':
+		if l.leaveContext() == StmtParensContext {
+			l.state = ExprState
+		} else {
+			l.state = SubscriptState
+		}
+		l.r.Move(1)
+		tt = PunctuatorToken
+	case '{':
+		l.enterContext(BracesContext)
+		l.state = ExprState
+		l.r.Move(1)
+		tt = PunctuatorToken
+	case '}':
+		if l.leaveContext() == TemplateContext && l.consumeTemplateToken() {
+			tt = TemplateToken
+		} else {
+			// will work incorrectly for objects or functions divided by something,
+			// but that's an extremely rare case
+			l.state = ExprState
+			l.r.Move(1)
+			tt = PunctuatorToken
+		}
+	case ']':
+		l.state = SubscriptState
+		l.r.Move(1)
+		tt = PunctuatorToken
+	case '[', ';', ',', '~', '?', ':':
+		l.state = ExprState
+		l.r.Move(1)
+		tt = PunctuatorToken
+	case '<', '>', '=', '!', '+', '-', '*', '%', '&', '|', '^':
+		if (c == '<' || (l.emptyLine && c == '-')) && l.consumeCommentToken() {
+			return CommentToken, l.r.Shift()
+		} else if l.consumeLongPunctuatorToken() {
+			l.state = ExprState
+			tt = PunctuatorToken
+		}
+	case '/':
+		if l.consumeCommentToken() {
+			return CommentToken, l.r.Shift()
+		} else if l.state == ExprState && l.consumeRegexpToken() {
+			l.state = SubscriptState
+			tt = RegexpToken
+		} else if l.consumeLongPunctuatorToken() {
+			l.state = ExprState
+			tt = PunctuatorToken
+		}
+	case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.':
+		if l.consumeNumericToken() {
+			tt = NumericToken
+			l.state = SubscriptState
+		} else if c == '.' {
+			l.state = PropNameState
+			l.r.Move(1)
+			tt = PunctuatorToken
+		}
+	case '\'', '"':
+		if l.consumeStringToken() {
+			l.state = SubscriptState
+			tt = StringToken
+		}
+	case ' ', '\t', '\v', '\f':
+		l.r.Move(1)
+		for l.consumeWhitespace() {
+		}
+		return WhitespaceToken, l.r.Shift()
+	case '\n', '\r':
+		l.r.Move(1)
+		for l.consumeLineTerminator() {
+		}
+		tt = LineTerminatorToken
+	case '`':
+		if l.consumeTemplateToken() {
+			tt = TemplateToken
+		}
+	default:
+		if l.consumeIdentifierToken() {
+			tt = IdentifierToken
+			if l.state != PropNameState {
+				switch hash := ToHash(l.r.Lexeme()); hash {
+				case 0, This, False, True, Null:
+					l.state = SubscriptState
+				case If, While, For, With:
+					l.state = StmtParensState
+				default:
+					// This will include keywords that can't be followed by a regexp, but only
+					// by a specified char (like `switch` or `try`), but we don't check for syntax
+					// errors as we don't attempt to parse a full JS grammar when streaming
+					l.state = ExprState
+				}
+			} else {
+				l.state = SubscriptState
+			}
+		} else if c >= 0xC0 {
+			if l.consumeWhitespace() {
+				for l.consumeWhitespace() {
+				}
+				return WhitespaceToken, l.r.Shift()
+			} else if l.consumeLineTerminator() {
+				for l.consumeLineTerminator() {
+				}
+				tt = LineTerminatorToken
+			}
+		} else if l.Err() != nil {
+			return ErrorToken, nil
+		}
+	}
+
+	l.emptyLine = tt == LineTerminatorToken
+
+	if tt == UnknownToken {
+		_, n := l.r.PeekRune(0)
+		l.r.Move(n)
+	}
+	return tt, l.r.Shift()
+}
+
+////////////////////////////////////////////////////////////////
+
+/*
+The following functions follow the specifications at http://www.ecma-international.org/ecma-262/5.1/
+*/
+
+func (l *Lexer) consumeWhitespace() bool {
+	c := l.r.Peek(0)
+	if c == ' ' || c == '\t' || c == '\v' || c == '\f' {
+		l.r.Move(1)
+		return true
+	} else if c >= 0xC0 {
+		if r, n := l.r.PeekRune(0); r == '\u00A0' || r == '\uFEFF' || unicode.Is(unicode.Zs, r) {
+			l.r.Move(n)
+			return true
+		}
+	}
+	return false
+}
+
+func (l *Lexer) consumeLineTerminator() bool {
+	c := l.r.Peek(0)
+	if c == '\n' {
+		l.r.Move(1)
+		return true
+	} else if c == '\r' {
+		if l.r.Peek(1) == '\n' {
+			l.r.Move(2)
+		} else {
+			l.r.Move(1)
+		}
+		return true
+	} else if c >= 0xC0 {
+		if r, n := l.r.PeekRune(0); r == '\u2028' || r == '\u2029' {
+			l.r.Move(n)
+			return true
+		}
+	}
+	return false
+}
+
+func (l *Lexer) consumeDigit() bool {
+	if c := l.r.Peek(0); c >= '0' && c <= '9' {
+		l.r.Move(1)
+		return true
+	}
+	return false
+}
+
+func (l *Lexer) consumeHexDigit() bool {
+	if c := l.r.Peek(0); (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F') {
+		l.r.Move(1)
+		return true
+	}
+	return false
+}
+
+func (l *Lexer) consumeBinaryDigit() bool {
+	if c := l.r.Peek(0); c == '0' || c == '1' {
+		l.r.Move(1)
+		return true
+	}
+	return false
+}
+
+func (l *Lexer) consumeOctalDigit() bool {
+	if c := l.r.Peek(0); c >= '0' && c <= '7' {
+		l.r.Move(1)
+		return true
+	}
+	return false
+}
+
+func (l *Lexer) consumeUnicodeEscape() bool {
+	if l.r.Peek(0) != '\\' || l.r.Peek(1) != 'u' {
+		return false
+	}
+	mark := l.r.Pos()
+	l.r.Move(2)
+	if c := l.r.Peek(0); c == '{' {
+		l.r.Move(1)
+		if l.consumeHexDigit() {
+			for l.consumeHexDigit() {
+			}
+			if c := l.r.Peek(0); c == '}' {
+				l.r.Move(1)
+				return true
+			}
+		}
+		l.r.Rewind(mark)
+		return false
+	} else if !l.consumeHexDigit() || !l.consumeHexDigit() || !l.consumeHexDigit() || !l.consumeHexDigit() {
+		l.r.Rewind(mark)
+		return false
+	}
+	return true
+}
+
+func (l *Lexer) consumeSingleLineComment() {
+	for {
+		c := l.r.Peek(0)
+		if c == '\r' || c == '\n' || c == 0 {
+			break
+		} else if c >= 0xC0 {
+			if r, _ := l.r.PeekRune(0); r == '\u2028' || r == '\u2029' {
+				break
+			}
+		}
+		l.r.Move(1)
+	}
+}
+
+////////////////////////////////////////////////////////////////
+
+func (l *Lexer) consumeCommentToken() bool {
+	c := l.r.Peek(0)
+	if c == '/' {
+		c = l.r.Peek(1)
+		if c == '/' {
+			// single line
+			l.r.Move(2)
+			l.consumeSingleLineComment()
+		} else if c == '*' {
+			// multi line
+			l.r.Move(2)
+			for {
+				c := l.r.Peek(0)
+				if c == '*' && l.r.Peek(1) == '/' {
+					l.r.Move(2)
+					return true
+				} else if c == 0 {
+					break
+				} else if l.consumeLineTerminator() {
+					l.emptyLine = true
+				} else {
+					l.r.Move(1)
+				}
+			}
+		} else {
+			return false
+		}
+	} else if c == '<' && l.r.Peek(1) == '!' && l.r.Peek(2) == '-' && l.r.Peek(3) == '-' {
+		// opening HTML-style single line comment
+		l.r.Move(4)
+		l.consumeSingleLineComment()
+	} else if c == '-' && l.r.Peek(1) == '-' && l.r.Peek(2) == '>' {
+		// closing HTML-style single line comment
+		// (only if current line didn't contain any meaningful tokens)
+		l.r.Move(3)
+		l.consumeSingleLineComment()
+	} else {
+		return false
+	}
+	return true
+}
+
+func (l *Lexer) consumeLongPunctuatorToken() bool {
+	c := l.r.Peek(0)
+	if c == '!' || c == '=' || c == '+' || c == '-' || c == '*' || c == '/' || c == '%' || c == '&' || c == '|' || c == '^' {
+		l.r.Move(1)
+		if l.r.Peek(0) == '=' {
+			l.r.Move(1)
+			if (c == '!' || c == '=') && l.r.Peek(0) == '=' {
+				l.r.Move(1)
+			}
+		} else if (c == '+' || c == '-' || c == '&' || c == '|') && l.r.Peek(0) == c {
+			l.r.Move(1)
+		} else if c == '=' && l.r.Peek(0) == '>' {
+			l.r.Move(1)
+		}
+	} else { // c == '<' || c == '>'
+		l.r.Move(1)
+		if l.r.Peek(0) == c {
+			l.r.Move(1)
+			if c == '>' && l.r.Peek(0) == '>' {
+				l.r.Move(1)
+			}
+		}
+		if l.r.Peek(0) == '=' {
+			l.r.Move(1)
+		}
+	}
+	return true
+}
+
+func (l *Lexer) consumeIdentifierToken() bool {
+	c := l.r.Peek(0)
+	if (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '$' || c == '_' {
+		l.r.Move(1)
+	} else if c >= 0xC0 {
+		if r, n := l.r.PeekRune(0); unicode.IsOneOf(identifierStart, r) {
+			l.r.Move(n)
+		} else {
+			return false
+		}
+	} else if !l.consumeUnicodeEscape() {
+		return false
+	}
+	for {
+		c := l.r.Peek(0)
+		if (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '$' || c == '_' {
+			l.r.Move(1)
+		} else if c >= 0xC0 {
+			if r, n := l.r.PeekRune(0); r == '\u200C' || r == '\u200D' || unicode.IsOneOf(identifierContinue, r) {
+				l.r.Move(n)
+			} else {
+				break
+			}
+		} else {
+			break
+		}
+	}
+	return true
+}
+
+func (l *Lexer) consumeNumericToken() bool {
+	// assume to be on 0 1 2 3 4 5 6 7 8 9 .
+	mark := l.r.Pos()
+	c := l.r.Peek(0)
+	if c == '0' {
+		l.r.Move(1)
+		if l.r.Peek(0) == 'x' || l.r.Peek(0) == 'X' {
+			l.r.Move(1)
+			if l.consumeHexDigit() {
+				for l.consumeHexDigit() {
+				}
+			} else {
+				l.r.Move(-1) // return just the zero
+			}
+			return true
+		} else if l.r.Peek(0) == 'b' || l.r.Peek(0) == 'B' {
+			l.r.Move(1)
+			if l.consumeBinaryDigit() {
+				for l.consumeBinaryDigit() {
+				}
+			} else {
+				l.r.Move(-1) // return just the zero
+			}
+			return true
+		} else if l.r.Peek(0) == 'o' || l.r.Peek(0) == 'O' {
+			l.r.Move(1)
+			if l.consumeOctalDigit() {
+				for l.consumeOctalDigit() {
+				}
+			} else {
+				l.r.Move(-1) // return just the zero
+			}
+			return true
+		}
+	} else if c != '.' {
+		for l.consumeDigit() {
+		}
+	}
+	if l.r.Peek(0) == '.' {
+		l.r.Move(1)
+		if l.consumeDigit() {
+			for l.consumeDigit() {
+			}
+		} else if c != '.' {
+			// . could belong to the next token
+			l.r.Move(-1)
+			return true
+		} else {
+			l.r.Rewind(mark)
+			return false
+		}
+	}
+	mark = l.r.Pos()
+	c = l.r.Peek(0)
+	if c == 'e' || c == 'E' {
+		l.r.Move(1)
+		c = l.r.Peek(0)
+		if c == '+' || c == '-' {
+			l.r.Move(1)
+		}
+		if !l.consumeDigit() {
+			// e could belong to the next token
+			l.r.Rewind(mark)
+			return true
+		}
+		for l.consumeDigit() {
+		}
+	}
+	return true
+}
+
+func (l *Lexer) consumeStringToken() bool {
+	// assume to be on ' or "
+	mark := l.r.Pos()
+	delim := l.r.Peek(0)
+	l.r.Move(1)
+	for {
+		c := l.r.Peek(0)
+		if c == delim {
+			l.r.Move(1)
+			break
+		} else if c == '\\' {
+			l.r.Move(1)
+			if !l.consumeLineTerminator() {
+				if c := l.r.Peek(0); c == delim || c == '\\' {
+					l.r.Move(1)
+				}
+			}
+			continue
+		} else if c == '\n' || c == '\r' {
+			l.r.Rewind(mark)
+			return false
+		} else if c >= 0xC0 {
+			if r, _ := l.r.PeekRune(0); r == '\u2028' || r == '\u2029' {
+				l.r.Rewind(mark)
+				return false
+			}
+		} else if c == 0 {
+			break
+		}
+		l.r.Move(1)
+	}
+	return true
+}
+
+func (l *Lexer) consumeRegexpToken() bool {
+	// assume to be on / and not /*
+	mark := l.r.Pos()
+	l.r.Move(1)
+	inClass := false
+	for {
+		c := l.r.Peek(0)
+		if !inClass && c == '/' {
+			l.r.Move(1)
+			break
+		} else if c == '[' {
+			inClass = true
+		} else if c == ']' {
+			inClass = false
+		} else if c == '\\' {
+			l.r.Move(1)
+			if l.consumeLineTerminator() {
+				l.r.Rewind(mark)
+				return false
+			}
+		} else if l.consumeLineTerminator() {
+			l.r.Rewind(mark)
+			return false
+		} else if c == 0 {
+			return true
+		}
+		l.r.Move(1)
+	}
+	// flags
+	for {
+		c := l.r.Peek(0)
+		if (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '$' || c == '_' {
+			l.r.Move(1)
+		} else if c >= 0xC0 {
+			if r, n := l.r.PeekRune(0); r == '\u200C' || r == '\u200D' || unicode.IsOneOf(identifierContinue, r) {
+				l.r.Move(n)
+			} else {
+				break
+			}
+		} else {
+			break
+		}
+	}
+	return true
+}
+
+func (l *Lexer) consumeTemplateToken() bool {
+	// assume to be on ` or } when already within template
+	mark := l.r.Pos()
+	l.r.Move(1)
+	for {
+		c := l.r.Peek(0)
+		if c == '`' {
+			l.state = SubscriptState
+			l.r.Move(1)
+			return true
+		} else if c == '$' && l.r.Peek(1) == '{' {
+			l.enterContext(TemplateContext)
+			l.state = ExprState
+			l.r.Move(2)
+			return true
+		} else if c == 0 {
+			l.r.Rewind(mark)
+			return false
+		}
+		l.r.Move(1)
+	}
+}
--- a/vendor/github.com/tdewolff/parse/js/lex_test.go
+++ b/vendor/github.com/tdewolff/parse/js/lex_test.go
@ -0,0 +1,152 @@
+package js // import "github.com/tdewolff/parse/js"
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"testing"
+
+	"github.com/tdewolff/test"
+)
+
+type TTs []TokenType
+
+func TestTokens(t *testing.T) {
+	var tokenTests = []struct {
+		js       string
+		expected []TokenType
+	}{
+		{" \t\v\f\u00A0\uFEFF\u2000", TTs{}}, // WhitespaceToken
+		{"\n\r\r\n\u2028\u2029", TTs{LineTerminatorToken}},
+		{"5.2 .04 0x0F 5e99", TTs{NumericToken, NumericToken, NumericToken, NumericToken}},
+		{"a = 'string'", TTs{IdentifierToken, PunctuatorToken, StringToken}},
+		{"/*comment*/ //comment", TTs{CommentToken, CommentToken}},
+		{"{ } ( ) [ ]", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{". ; , < > <=", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{">= == != === !==", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{"+ - * % ++ --", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{"<< >> >>> & | ^", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{"! ~ && || ? :", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{"= += -= *= %= <<=", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{">>= >>>= &= |= ^= =>", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{"a = /.*/g;", TTs{IdentifierToken, PunctuatorToken, RegexpToken, PunctuatorToken}},
+
+		{"/*co\nm\u2028m/*ent*/ //co//mment\u2029//comment", TTs{CommentToken, CommentToken, LineTerminatorToken, CommentToken}},
+		{"<!-", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{"1<!--2\n", TTs{NumericToken, CommentToken, LineTerminatorToken}},
+		{"x=y-->10\n", TTs{IdentifierToken, PunctuatorToken, IdentifierToken, PunctuatorToken, PunctuatorToken, NumericToken, LineTerminatorToken}},
+		{"  /*comment*/ -->nothing\n", TTs{CommentToken, CommentToken, LineTerminatorToken}},
+		{"1 /*comment\nmultiline*/ -->nothing\n", TTs{NumericToken, CommentToken, CommentToken, LineTerminatorToken}},
+		{"$ _\u200C \\u2000 \u200C", TTs{IdentifierToken, IdentifierToken, IdentifierToken, UnknownToken}},
+		{">>>=>>>>=", TTs{PunctuatorToken, PunctuatorToken, PunctuatorToken}},
+		{"1/", TTs{NumericToken, PunctuatorToken}},
+		{"1/=", TTs{NumericToken, PunctuatorToken}},
+		{"010xF", TTs{NumericToken, NumericToken, IdentifierToken}},
+		{"50e+-0", TTs{NumericToken, IdentifierToken, PunctuatorToken, PunctuatorToken, NumericToken}},
+		{"'str\\i\\'ng'", TTs{StringToken}},
+		{"'str\\\\'abc", TTs{StringToken, IdentifierToken}},
+		{"'str\\\ni\\\\u00A0ng'", TTs{StringToken}},
+		{"a = /[a-z/]/g", TTs{IdentifierToken, PunctuatorToken, RegexpToken}},
+		{"a=/=/g1", TTs{IdentifierToken, PunctuatorToken, RegexpToken}},
+		{"a = /'\\\\/\n", TTs{IdentifierToken, PunctuatorToken, RegexpToken, LineTerminatorToken}},
+		{"a=/\\//g1", TTs{IdentifierToken, PunctuatorToken, RegexpToken}},
+		{"new RegExp(a + /\\d{1,2}/.source)", TTs{IdentifierToken, IdentifierToken, PunctuatorToken, IdentifierToken, PunctuatorToken, RegexpToken, PunctuatorToken, IdentifierToken, PunctuatorToken}},
+
+		{"0b0101 0o0707 0b17", TTs{NumericToken, NumericToken, NumericToken, NumericToken}},
+		{"`template`", TTs{TemplateToken}},
+		{"`a${x+y}b`", TTs{TemplateToken, IdentifierToken, PunctuatorToken, IdentifierToken, TemplateToken}},
+		{"`temp\nlate`", TTs{TemplateToken}},
+		{"`outer${{x: 10}}bar${ raw`nested${2}endnest` }end`", TTs{TemplateToken, PunctuatorToken, IdentifierToken, PunctuatorToken, NumericToken, PunctuatorToken, TemplateToken, IdentifierToken, TemplateToken, NumericToken, TemplateToken, TemplateToken}},
+
+		// early endings
+		{"'string", TTs{StringToken}},
+		{"'\n '\u2028", TTs{UnknownToken, LineTerminatorToken, UnknownToken, LineTerminatorToken}},
+		{"'str\\\U00100000ing\\0'", TTs{StringToken}},
+		{"'strin\\00g'", TTs{StringToken}},
+		{"/*comment", TTs{CommentToken}},
+		{"a=/regexp", TTs{IdentifierToken, PunctuatorToken, RegexpToken}},
+		{"\\u002", TTs{UnknownToken, IdentifierToken}},
+
+		// coverage
+		{"Ø a〉", TTs{IdentifierToken, IdentifierToken, UnknownToken}},
+		{"0xg 0.f", TTs{NumericToken, IdentifierToken, NumericToken, PunctuatorToken, IdentifierToken}},
+		{"0bg 0og", TTs{NumericToken, IdentifierToken, NumericToken, IdentifierToken}},
+		{"\u00A0\uFEFF\u2000", TTs{}},
+		{"\u2028\u2029", TTs{LineTerminatorToken}},
+		{"\\u0029ident", TTs{IdentifierToken}},
+		{"\\u{0029FEF}ident", TTs{IdentifierToken}},
+		{"\\u{}", TTs{UnknownToken, IdentifierToken, PunctuatorToken, PunctuatorToken}},
+		{"\\ugident", TTs{UnknownToken, IdentifierToken}},
+		{"'str\u2028ing'", TTs{UnknownToken, IdentifierToken, LineTerminatorToken, IdentifierToken, StringToken}},
+		{"a=/\\\n", TTs{IdentifierToken, PunctuatorToken, PunctuatorToken, UnknownToken, LineTerminatorToken}},
+		{"a=/x/\u200C\u3009", TTs{IdentifierToken, PunctuatorToken, RegexpToken, UnknownToken}},
+		{"a=/x\n", TTs{IdentifierToken, PunctuatorToken, PunctuatorToken, IdentifierToken, LineTerminatorToken}},
+
+		{"return /abc/;", TTs{IdentifierToken, RegexpToken, PunctuatorToken}},
+		{"yield /abc/;", TTs{IdentifierToken, RegexpToken, PunctuatorToken}},
+		{"a/b/g", TTs{IdentifierToken, PunctuatorToken, IdentifierToken, PunctuatorToken, IdentifierToken}},
+		{"{}/1/g", TTs{PunctuatorToken, PunctuatorToken, RegexpToken}},
+		{"i(0)/1/g", TTs{IdentifierToken, PunctuatorToken, NumericToken, PunctuatorToken, PunctuatorToken, NumericToken, PunctuatorToken, IdentifierToken}},
+		{"if(0)/1/g", TTs{IdentifierToken, PunctuatorToken, NumericToken, PunctuatorToken, RegexpToken}},
+		{"a.if(0)/1/g", TTs{IdentifierToken, PunctuatorToken, IdentifierToken, PunctuatorToken, NumericToken, PunctuatorToken, PunctuatorToken, NumericToken, PunctuatorToken, IdentifierToken}},
+		{"while(0)/1/g", TTs{IdentifierToken, PunctuatorToken, NumericToken, PunctuatorToken, RegexpToken}},
+		{"for(;;)/1/g", TTs{IdentifierToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, RegexpToken}},
+		{"with(0)/1/g", TTs{IdentifierToken, PunctuatorToken, NumericToken, PunctuatorToken, RegexpToken}},
+		{"this/1/g", TTs{IdentifierToken, PunctuatorToken, NumericToken, PunctuatorToken, IdentifierToken}},
+		{"case /1/g:", TTs{IdentifierToken, RegexpToken, PunctuatorToken}},
+		{"function f(){}/1/g", TTs{IdentifierToken, IdentifierToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, PunctuatorToken, RegexpToken}},
+		{"this.return/1/g", TTs{IdentifierToken, PunctuatorToken, IdentifierToken, PunctuatorToken, NumericToken, PunctuatorToken, IdentifierToken}},
+		{"(a+b)/1/g", TTs{PunctuatorToken, IdentifierToken, PunctuatorToken, IdentifierToken, PunctuatorToken, PunctuatorToken, NumericToken, PunctuatorToken, IdentifierToken}},
+
+		// go fuzz
+		{"`", TTs{UnknownToken}},
+	}
+
+	for _, tt := range tokenTests {
+		t.Run(tt.js, func(t *testing.T) {
+			l := NewLexer(bytes.NewBufferString(tt.js))
+			i := 0
+			j := 0
+			for {
+				token, _ := l.Next()
+				j++
+				if token == ErrorToken {
+					test.T(t, l.Err(), io.EOF)
+					test.T(t, i, len(tt.expected), "when error occurred we must be at the end")
+					break
+				} else if token == WhitespaceToken {
+					continue
+				}
+				if i < len(tt.expected) {
+					if token != tt.expected[i] {
+						test.String(t, token.String(), tt.expected[i].String(), "token types must match")
+						break
+					}
+				} else {
+					test.Fail(t, "index", i, "must not exceed expected token types size", len(tt.expected))
+					break
+				}
+				i++
+			}
+		})
+	}
+
+	test.T(t, WhitespaceToken.String(), "Whitespace")
+	test.T(t, TokenType(100).String(), "Invalid(100)")
+}
+
+////////////////////////////////////////////////////////////////
+
+func ExampleNewLexer() {
+	l := NewLexer(bytes.NewBufferString("var x = 'lorem ipsum';"))
+	out := ""
+	for {
+		tt, data := l.Next()
+		if tt == ErrorToken {
+			break
+		}
+		out += string(data)
+	}
+	fmt.Println(out)
+	// Output: var x = 'lorem ipsum';
+}