vendor tsgo

This commit is contained in:
2026-07-09 16:50:43 -04:00
parent c06ea2e5a4
commit 98978e4930
5804 changed files with 1556156 additions and 101 deletions

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@@ -0,0 +1,380 @@
// Package stringutil Exports common rune utilities for parsing and emitting javascript
package stringutil
import (
"regexp"
"strings"
"unicode"
"unicode/utf16"
"unicode/utf8"
)
func IsWhiteSpaceLike(ch rune) bool {
return IsWhiteSpaceSingleLine(ch) || IsLineBreak(ch)
}
func IsWhiteSpaceSingleLine(ch rune) bool {
// Note: nextLine is in the Zs space, and should be considered to be a whitespace.
// It is explicitly not a line-break as it isn't in the exact set specified by EcmaScript.
switch ch {
case
' ', // space
'\t', // tab
'\v', // verticalTab
'\f', // formFeed
0x0085, // nextLine
0x00A0, // nonBreakingSpace
0x1680, // ogham
0x2000, // enQuad
0x2001, // emQuad
0x2002, // enSpace
0x2003, // emSpace
0x2004, // threePerEmSpace
0x2005, // fourPerEmSpace
0x2006, // sixPerEmSpace
0x2007, // figureSpace
0x2008, // punctuationEmSpace
0x2009, // thinSpace
0x200A, // hairSpace
0x200B, // zeroWidthSpace
0x202F, // narrowNoBreakSpace
0x205F, // mathematicalSpace
0x3000, // ideographicSpace
0xFEFF: // byteOrderMark
return true
}
return false
}
func IsLineBreak(ch rune) bool {
// ES5 7.3:
// The ECMAScript line terminator characters are listed in Table 3.
// Table 3: Line Terminator Characters
// Code Unit Value Name Formal Name
// \u000A Line Feed <LF>
// \u000D Carriage Return <CR>
// \u2028 Line separator <LS>
// \u2029 Paragraph separator <PS>
// Only the characters in Table 3 are treated as line terminators. Other new line or line
// breaking characters are treated as white space but not as line terminators.
switch ch {
case
'\n', // lineFeed
'\r', // carriageReturn
0x2028, // lineSeparator
0x2029: // paragraphSeparator
return true
}
return false
}
func IsDigit(ch rune) bool {
return ch >= '0' && ch <= '9'
}
func IsOctalDigit(ch rune) bool {
return ch >= '0' && ch <= '7'
}
func IsHexDigit(ch rune) bool {
return ch >= '0' && ch <= '9' || ch >= 'A' && ch <= 'F' || ch >= 'a' && ch <= 'f'
}
func IsASCIILetter(ch rune) bool {
return ch >= 'A' && ch <= 'Z' || ch >= 'a' && ch <= 'z'
}
func ContainsNonASCII(s string) bool {
for i := range len(s) {
if s[i] >= utf8.RuneSelf {
return true
}
}
return false
}
func SplitLines(text string) []string {
lines := make([]string, 0, strings.Count(text, "\n")+1) // preallocate
start := 0
pos := 0
for pos < len(text) {
switch text[pos] {
case '\r':
if pos+1 < len(text) && text[pos+1] == '\n' {
lines = append(lines, text[start:pos])
pos += 2
start = pos
continue
}
fallthrough
case '\n':
lines = append(lines, text[start:pos])
pos++
start = pos
continue
}
pos++
}
if start < len(text) {
lines = append(lines, text[start:])
}
return lines
}
func GuessIndentation(lines []string) int {
const MAX_SMI_X86 int = 0x3fff_ffff
indentation := MAX_SMI_X86
for _, line := range lines {
if len(line) == 0 {
continue
}
i := 0
for i < len(line) && i < indentation {
ch, size := utf8.DecodeRuneInString(line[i:])
if !IsWhiteSpaceLike(ch) {
break
}
i += size
}
if i < indentation {
indentation = i
}
if indentation == 0 {
return 0
}
}
if indentation == MAX_SMI_X86 {
return 0
}
return indentation
}
// https://tc39.es/ecma262/multipage/global-object.html#sec-encodeuri-uri
func EncodeURI(s string) string {
var builder strings.Builder
for i := range len(s) {
b := s[i]
if !shouldEscapeForEncodeURI(b) {
builder.WriteByte(b)
continue
}
for _, escaped := range []byte(s[i : i+1]) {
builder.WriteByte('%')
builder.WriteByte(upperhex[escaped>>4])
builder.WriteByte(upperhex[escaped&0x0f])
}
}
return builder.String()
}
const upperhex = "0123456789ABCDEF"
func shouldEscapeForEncodeURI(b byte) bool {
switch {
case b >= 'A' && b <= 'Z':
return false
case b >= 'a' && b <= 'z':
return false
case b >= '0' && b <= '9':
return false
}
switch b {
case ';', '/', '?', ':', '@', '&', '=', '+', '$', ',', '#', '-', '_', '.', '!', '~', '*', '\'', '(', ')':
return false
default:
return true
}
}
func getByteOrderMarkLength(text string) int {
if len(text) >= 1 {
ch0 := text[0]
if ch0 == 0xfe {
if len(text) >= 2 && text[1] == 0xff {
return 2 // utf16be
}
return 0
}
if ch0 == 0xff {
if len(text) >= 2 && text[1] == 0xfe {
return 2 // utf16le
}
return 0
}
if ch0 == 0xef {
if len(text) >= 3 && text[1] == 0xbb && text[2] == 0xbf {
return 3 // utf8
}
return 0
}
}
return 0
}
func RemoveByteOrderMark(text string) string {
length := getByteOrderMarkLength(text)
if length > 0 {
return text[length:]
}
return text
}
func AddUTF8ByteOrderMark(text string) string {
if getByteOrderMarkLength(text) == 0 {
return "\xEF\xBB\xBF" + text
}
return text
}
func StripQuotes(name string) string {
if len(name) < 2 {
return name
}
firstChar, _ := utf8.DecodeRuneInString(name)
lastChar, _ := utf8.DecodeLastRuneInString(name)
if firstChar == lastChar && (firstChar == '\'' || firstChar == '"' || firstChar == '`') {
return name[1 : len(name)-1]
}
return name
}
var matchSlashSomething = regexp.MustCompile(`\\.`)
func matchSlashReplacer(in string) string {
return in[1:]
}
func UnquoteString(str string) string {
// strconv.Unquote is insufficient as that only handles a single character inside single quotes, as those are character literals in go
inner := StripQuotes(str)
// In strada we do str.replace(/\\./g, s => s.substring(1)) - which is to say, replace all backslash-something with just something
// That's replicated here faithfully, but it seems wrong! This should probably be an actual unquote operation?
return matchSlashSomething.ReplaceAllStringFunc(inner, matchSlashReplacer)
}
func LowerFirstChar(str string) string {
char, size := utf8.DecodeRuneInString(str)
if size > 0 {
return string(unicode.ToLower(char)) + str[size:]
}
return str
}
func TruncateByRunes(str string, maxLength int) string {
if len(str) < maxLength {
return str
}
if maxLength <= 0 {
return ""
}
var runeCount int
for i := range str {
runeCount++
if runeCount > maxLength {
return str[:i]
}
}
return str
}
const (
// SurrogateLowStart is the boundary between the high and low halves of the
// UTF-16 surrogate range. unicode/utf16 only exposes IsSurrogate for the
// whole range, so this split point is defined here to distinguish the two.
SurrogateLowStart = 0xDC00
)
func IsHighSurrogate(ch rune) bool {
return utf16.IsSurrogate(ch) && ch < SurrogateLowStart
}
func IsLowSurrogate(ch rune) bool {
return utf16.IsSurrogate(ch) && ch >= SurrogateLowStart
}
func IsSurrogate(ch rune) bool {
return utf16.IsSurrogate(ch)
}
func SurrogatePairToCodePoint(high rune, low rune) rune {
return utf16.DecodeRune(high, low)
}
func CodePointToSurrogatePair(ch rune) (high rune, low rune) {
return utf16.EncodeRune(ch)
}
const (
// A lone surrogate (U+D800U+DFFF) cannot be represented in valid UTF-8, so
// EncodeJSStringRune stores it as the 3-byte CESU-8/WTF-8 sentinel that UTF-8
// would use for that code point if surrogates were encodable. unicode/utf8
// and unicode/utf16 deliberately refuse to encode or decode surrogates, so
// the byte math is spelled out here.
//
// Byte layout for a code point cp in U+D000U+DFFF (lead nibble 0xD):
// byte0 = 0xE0 | (cp >> 12) == 0xED
// byte1 = 0x80 | ((cp >> 6) & 0x3F)
// byte2 = 0x80 | (cp & 0x3F)
surrogateUTF8Lead = 0xED // byte0, shared by the whole U+D000U+DFFF block
surrogateUTF8LeadBits = 0xD000 // (surrogateUTF8Lead & 0x0F) << 12, byte0's decoded contribution
utf8ContMarker = 0x80 // continuation byte marker / min value (10xxxxxx)
utf8ContMax = 0xBF // continuation byte max value
utf8ContMask = 0x3F // data bits carried by a continuation byte
// byte1 bounds that pin the block down to the surrogate range U+D800U+DFFF:
// 0xD800 -> 0xA0, 0xDFFF -> 0xBF.
surrogateUTF8Byte1Min = 0xA0
surrogateUTF8Byte1Max = 0xBF
)
func EncodeJSStringRune(ch rune) string {
if IsSurrogate(ch) {
return string([]byte{
surrogateUTF8Lead,
byte(utf8ContMarker | ((ch >> 6) & utf8ContMask)),
byte(utf8ContMarker | (ch & utf8ContMask)),
})
}
return string(ch)
}
func DecodeJSStringRune(s string) (rune, int) {
if len(s) >= 3 &&
s[0] == surrogateUTF8Lead &&
s[1] >= surrogateUTF8Byte1Min && s[1] <= surrogateUTF8Byte1Max &&
s[2] >= utf8ContMarker && s[2] <= utf8ContMax {
return surrogateUTF8LeadBits | rune(s[1]&utf8ContMask)<<6 | rune(s[2]&utf8ContMask), 3
}
return utf8.DecodeRuneInString(s)
}
// CombineSurrogatePairs canonicalizes a JS-string value produced by
// concatenation, merging any adjacent high+low surrogate sentinel pair (as
// written by EncodeJSStringRune) into the single supplementary code point they
// represent. This mirrors how concatenating two UTF-16 code units forms a
// surrogate pair in a JavaScript string. It must be applied wherever separately
// scanned string values are joined, since each half is only a lone surrogate
// until it meets its partner. Strings without a lone-surrogate sentinel (the
// common case) are returned unchanged.
func CombineSurrogatePairs(s string) string {
if strings.IndexByte(s, surrogateUTF8Lead) < 0 {
return s
}
var b strings.Builder
b.Grow(len(s))
for i := 0; i < len(s); {
r, size := DecodeJSStringRune(s[i:])
if IsHighSurrogate(r) {
if low, lowSize := DecodeJSStringRune(s[i+size:]); IsLowSurrogate(low) {
b.WriteRune(SurrogatePairToCodePoint(r, low))
i += size + lowSize
continue
}
}
b.WriteString(s[i : i+size])
i += size
}
return b.String()
}