From 76cb9c2a39d477a64824a985ade40507e3bbade1 Mon Sep 17 00:00:00 2001 From: Adam Mathes Date: Fri, 13 Feb 2026 21:34:48 -0800 Subject: feat(vanilla): add testing infrastructure and tests (NK-wjnczv) --- vanilla/node_modules/es-module-lexer/lexer.js | 925 ++++++++++++++++++++++++++ 1 file changed, 925 insertions(+) create mode 100644 vanilla/node_modules/es-module-lexer/lexer.js (limited to 'vanilla/node_modules/es-module-lexer/lexer.js') diff --git a/vanilla/node_modules/es-module-lexer/lexer.js b/vanilla/node_modules/es-module-lexer/lexer.js new file mode 100644 index 0000000..587fafe --- /dev/null +++ b/vanilla/node_modules/es-module-lexer/lexer.js @@ -0,0 +1,925 @@ +let source, pos, end, + openTokenDepth, + lastTokenPos, + openTokenPosStack, + openClassPosStack, + curDynamicImport, + templateStackDepth, + facade, + lastSlashWasDivision, + nextBraceIsClass, + templateDepth, + templateStack, + imports, + exports, + name; + +function addImport (ss, s, e, d) { + const impt = { ss, se: d === -2 ? e : d === -1 ? e + 1 : 0, s, e, d, a: -1, n: undefined }; + imports.push(impt); + return impt; +} + +function addExport (s, e, ls, le) { + exports.push({ + s, + e, + ls, + le, + n: s[0] === '"' ? readString(s, '"') : s[0] === "'" ? readString(s, "'") : source.slice(s, e), + ln: ls[0] === '"' ? readString(ls, '"') : ls[0] === "'" ? readString(ls, "'") : source.slice(ls, le) + }); +} + +function readName (impt) { + let { d, s } = impt; + if (d !== -1) + s++; + impt.n = readString(s, source.charCodeAt(s - 1)); +} + +// Note: parsing is based on the _assumption_ that the source is already valid +export function parse (_source, _name) { + openTokenDepth = 0; + curDynamicImport = null; + templateDepth = -1; + lastTokenPos = -1; + lastSlashWasDivision = false; + templateStack = Array(1024); + templateStackDepth = 0; + openTokenPosStack = Array(1024); + openClassPosStack = Array(1024); + nextBraceIsClass = false; + facade = true; + name = _name || '@'; + + imports = []; + exports = []; + + source = _source; + pos = -1; + end = source.length - 1; + let ch = 0; + + // start with a pure "module-only" parser + m: while (pos++ < end) { + ch = source.charCodeAt(pos); + + if (ch === 32 || ch < 14 && ch > 8) + continue; + + switch (ch) { + case 101/*e*/: + if (openTokenDepth === 0 && keywordStart(pos) && source.startsWith('xport', pos + 1)) { + tryParseExportStatement(); + // export might have been a non-pure declaration + if (!facade) { + lastTokenPos = pos; + break m; + } + } + break; + case 105/*i*/: + if (keywordStart(pos) && source.startsWith('mport', pos + 1)) + tryParseImportStatement(); + break; + case 59/*;*/: + break; + case 47/*/*/: { + const next_ch = source.charCodeAt(pos + 1); + if (next_ch === 47/*/*/) { + lineComment(); + // dont update lastToken + continue; + } + else if (next_ch === 42/***/) { + blockComment(true); + // dont update lastToken + continue; + } + // fallthrough + } + default: + // as soon as we hit a non-module token, we go to main parser + facade = false; + pos--; + break m; + } + lastTokenPos = pos; + } + + while (pos++ < end) { + ch = source.charCodeAt(pos); + + if (ch === 32 || ch < 14 && ch > 8) + continue; + + switch (ch) { + case 101/*e*/: + if (openTokenDepth === 0 && keywordStart(pos) && source.startsWith('xport', pos + 1)) + tryParseExportStatement(); + break; + case 105/*i*/: + if (keywordStart(pos) && source.startsWith('mport', pos + 1)) + tryParseImportStatement(); + break; + case 99/*c*/: + if (keywordStart(pos) && source.startsWith('lass', pos + 1) && isBrOrWs(source.charCodeAt(pos + 5))) + nextBraceIsClass = true; + break; + case 40/*(*/: + openTokenPosStack[openTokenDepth++] = lastTokenPos; + break; + case 41/*)*/: + if (openTokenDepth === 0) + syntaxError(); + openTokenDepth--; + if (curDynamicImport && curDynamicImport.d === openTokenPosStack[openTokenDepth]) { + if (curDynamicImport.e === 0) + curDynamicImport.e = pos; + curDynamicImport.se = pos; + curDynamicImport = null; + } + break; + case 123/*{*/: + // dynamic import followed by { is not a dynamic import (so remove) + // this is a sneaky way to get around { import () {} } v { import () } + // block / object ambiguity without a parser (assuming source is valid) + if (source.charCodeAt(lastTokenPos) === 41/*)*/ && imports.length && imports[imports.length - 1].e === lastTokenPos) { + imports.pop(); + } + openClassPosStack[openTokenDepth] = nextBraceIsClass; + nextBraceIsClass = false; + openTokenPosStack[openTokenDepth++] = lastTokenPos; + break; + case 125/*}*/: + if (openTokenDepth === 0) + syntaxError(); + if (openTokenDepth-- === templateDepth) { + templateDepth = templateStack[--templateStackDepth]; + templateString(); + } + else { + if (templateDepth !== -1 && openTokenDepth < templateDepth) + syntaxError(); + } + break; + case 39/*'*/: + case 34/*"*/: + stringLiteral(ch); + break; + case 47/*/*/: { + const next_ch = source.charCodeAt(pos + 1); + if (next_ch === 47/*/*/) { + lineComment(); + // dont update lastToken + continue; + } + else if (next_ch === 42/***/) { + blockComment(true); + // dont update lastToken + continue; + } + else { + // Division / regex ambiguity handling based on checking backtrack analysis of: + // - what token came previously (lastToken) + // - if a closing brace or paren, what token came before the corresponding + // opening brace or paren (lastOpenTokenIndex) + const lastToken = source.charCodeAt(lastTokenPos); + const lastExport = exports[exports.length - 1]; + if (isExpressionPunctuator(lastToken) && + !(lastToken === 46/*.*/ && (source.charCodeAt(lastTokenPos - 1) >= 48/*0*/ && source.charCodeAt(lastTokenPos - 1) <= 57/*9*/)) && + !(lastToken === 43/*+*/ && source.charCodeAt(lastTokenPos - 1) === 43/*+*/) && !(lastToken === 45/*-*/ && source.charCodeAt(lastTokenPos - 1) === 45/*-*/) || + lastToken === 41/*)*/ && isParenKeyword(openTokenPosStack[openTokenDepth]) || + lastToken === 125/*}*/ && (isExpressionTerminator(openTokenPosStack[openTokenDepth]) || openClassPosStack[openTokenDepth]) || + lastToken === 47/*/*/ && lastSlashWasDivision || + isExpressionKeyword(lastTokenPos) || + !lastToken) { + regularExpression(); + lastSlashWasDivision = false; + } + else if (lastExport && lastTokenPos >= lastExport.s && lastTokenPos <= lastExport.e) { + // export default /some-regexp/ + regularExpression(); + lastSlashWasDivision = false; + } + else { + lastSlashWasDivision = true; + } + } + break; + } + case 96/*`*/: + templateString(); + break; + } + lastTokenPos = pos; + } + + if (templateDepth !== -1 || openTokenDepth) + syntaxError(); + + return [imports, exports, facade]; +} + +function tryParseImportStatement () { + const startPos = pos; + + pos += 6; + + let ch = commentWhitespace(true); + + switch (ch) { + // dynamic import + case 40/*(*/: + openTokenPosStack[openTokenDepth++] = startPos; + if (source.charCodeAt(lastTokenPos) === 46/*.*/) + return; + // dynamic import indicated by positive d + const impt = addImport(startPos, pos + 1, 0, startPos); + curDynamicImport = impt; + // try parse a string, to record a safe dynamic import string + pos++; + ch = commentWhitespace(true); + if (ch === 39/*'*/ || ch === 34/*"*/) { + stringLiteral(ch); + } + else { + pos--; + return; + } + pos++; + ch = commentWhitespace(true); + if (ch === 44/*,*/) { + impt.e = pos; + pos++; + ch = commentWhitespace(true); + impt.a = pos; + readName(impt); + pos--; + } + else if (ch === 41/*)*/) { + openTokenDepth--; + impt.e = pos; + impt.se = pos; + readName(impt); + } + else { + pos--; + } + return; + // import.meta + case 46/*.*/: + pos++; + ch = commentWhitespace(true); + // import.meta indicated by d === -2 + if (ch === 109/*m*/ && source.startsWith('eta', pos + 1) && source.charCodeAt(lastTokenPos) !== 46/*.*/) + addImport(startPos, startPos, pos + 4, -2); + return; + + default: + // no space after "import" -> not an import keyword + if (pos === startPos + 6) + break; + case 34/*"*/: + case 39/*'*/: + case 123/*{*/: + case 42/***/: + // import statement only permitted at base-level + if (openTokenDepth !== 0) { + pos--; + return; + } + while (pos < end) { + ch = source.charCodeAt(pos); + if (ch === 39/*'*/ || ch === 34/*"*/) { + readImportString(startPos, ch); + return; + } + pos++; + } + syntaxError(); + } +} + +function tryParseExportStatement () { + const sStartPos = pos; + const prevExport = exports.length; + + pos += 6; + + const curPos = pos; + + let ch = commentWhitespace(true); + + if (pos === curPos && !isPunctuator(ch)) + return; + + switch (ch) { + // export default ... + case 100/*d*/: + addExport(pos, pos + 7, -1, -1); + return; + + // export async? function*? name () { + case 97/*a*/: + pos += 5; + commentWhitespace(true); + // fallthrough + case 102/*f*/: + pos += 8; + ch = commentWhitespace(true); + if (ch === 42/***/) { + pos++; + ch = commentWhitespace(true); + } + const startPos = pos; + ch = readToWsOrPunctuator(ch); + addExport(startPos, pos, startPos, pos); + pos--; + return; + + // export class name ... + case 99/*c*/: + if (source.startsWith('lass', pos + 1) && isBrOrWsOrPunctuatorNotDot(source.charCodeAt(pos + 5))) { + pos += 5; + ch = commentWhitespace(true); + const startPos = pos; + ch = readToWsOrPunctuator(ch); + addExport(startPos, pos, startPos, pos); + pos--; + return; + } + pos += 2; + // fallthrough + + // export var/let/const name = ...(, name = ...)+ + case 118/*v*/: + case 109/*l*/: + // destructured initializations not currently supported (skipped for { or [) + // also, lexing names after variable equals is skipped (export var p = function () { ... }, q = 5 skips "q") + pos += 2; + facade = false; + do { + pos++; + ch = commentWhitespace(true); + const startPos = pos; + ch = readToWsOrPunctuator(ch); + // dont yet handle [ { destructurings + if (ch === 123/*{*/ || ch === 91/*[*/) { + pos--; + return; + } + if (pos === startPos) + return; + addExport(startPos, pos, startPos, pos); + ch = commentWhitespace(true); + if (ch === 61/*=*/) { + pos--; + return; + } + } while (ch === 44/*,*/); + pos--; + return; + + + // export {...} + case 123/*{*/: + pos++; + ch = commentWhitespace(true); + while (true) { + const startPos = pos; + readToWsOrPunctuator(ch); + const endPos = pos; + commentWhitespace(true); + ch = readExportAs(startPos, endPos); + // , + if (ch === 44/*,*/) { + pos++; + ch = commentWhitespace(true); + } + if (ch === 125/*}*/) + break; + if (pos === startPos) + return syntaxError(); + if (pos > end) + return syntaxError(); + } + pos++; + ch = commentWhitespace(true); + break; + + // export * + // export * as X + case 42/***/: + pos++; + commentWhitespace(true); + ch = readExportAs(pos, pos); + ch = commentWhitespace(true); + break; + } + + // from ... + if (ch === 102/*f*/ && source.startsWith('rom', pos + 1)) { + pos += 4; + readImportString(sStartPos, commentWhitespace(true)); + + // There were no local names. + for (let i = prevExport; i < exports.length; ++i) { + exports[i].ls = exports[i].le = -1; + exports[i].ln = undefined; + } + } + else { + pos--; + } +} + +/* + * Ported from Acorn + * + * MIT License + + * Copyright (C) 2012-2020 by various contributors (see AUTHORS) + + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +let acornPos; +function readString (start, quote) { + acornPos = start; + let out = '', chunkStart = acornPos; + for (;;) { + if (acornPos >= source.length) syntaxError(); + const ch = source.charCodeAt(acornPos); + if (ch === quote) break; + if (ch === 92) { // '\' + out += source.slice(chunkStart, acornPos); + out += readEscapedChar(); + chunkStart = acornPos; + } + else if (ch === 0x2028 || ch === 0x2029) { + ++acornPos; + } + else { + if (isBr(ch)) syntaxError(); + ++acornPos; + } + } + out += source.slice(chunkStart, acornPos++); + return out; +} + +// Used to read escaped characters + +function readEscapedChar () { + let ch = source.charCodeAt(++acornPos); + ++acornPos; + switch (ch) { + case 110: return '\n'; // 'n' -> '\n' + case 114: return '\r'; // 'r' -> '\r' + case 120: return String.fromCharCode(readHexChar(2)); // 'x' + case 117: return readCodePointToString(); // 'u' + case 116: return '\t'; // 't' -> '\t' + case 98: return '\b'; // 'b' -> '\b' + case 118: return '\u000b'; // 'v' -> '\u000b' + case 102: return '\f'; // 'f' -> '\f' + case 13: if (source.charCodeAt(acornPos) === 10) ++acornPos; // '\r\n' + case 10: // ' \n' + return ''; + case 56: + case 57: + syntaxError(); + default: + if (ch >= 48 && ch <= 55) { + let octalStr = source.substr(acornPos - 1, 3).match(/^[0-7]+/)[0]; + let octal = parseInt(octalStr, 8); + if (octal > 255) { + octalStr = octalStr.slice(0, -1); + octal = parseInt(octalStr, 8); + } + acornPos += octalStr.length - 1; + ch = source.charCodeAt(acornPos); + if (octalStr !== '0' || ch === 56 || ch === 57) + syntaxError(); + return String.fromCharCode(octal); + } + if (isBr(ch)) { + // Unicode new line characters after \ get removed from output in both + // template literals and strings + return ''; + } + return String.fromCharCode(ch); + } +} + +// Used to read character escape sequences ('\x', '\u', '\U'). + +function readHexChar (len) { + const start = acornPos; + let total = 0, lastCode = 0; + for (let i = 0; i < len; ++i, ++acornPos) { + let code = source.charCodeAt(acornPos), val; + + if (code === 95) { + if (lastCode === 95 || i === 0) syntaxError(); + lastCode = code; + continue; + } + + if (code >= 97) val = code - 97 + 10; // a + else if (code >= 65) val = code - 65 + 10; // A + else if (code >= 48 && code <= 57) val = code - 48; // 0-9 + else break; + if (val >= 16) break; + lastCode = code; + total = total * 16 + val; + } + + if (lastCode === 95 || acornPos - start !== len) syntaxError(); + + return total; +} + +// Read a string value, interpreting backslash-escapes. + +function readCodePointToString () { + const ch = source.charCodeAt(acornPos); + let code; + if (ch === 123) { // '{' + ++acornPos; + code = readHexChar(source.indexOf('}', acornPos) - acornPos); + ++acornPos; + if (code > 0x10FFFF) syntaxError(); + } else { + code = readHexChar(4); + } + // UTF-16 Decoding + if (code <= 0xFFFF) return String.fromCharCode(code); + code -= 0x10000; + return String.fromCharCode((code >> 10) + 0xD800, (code & 1023) + 0xDC00); +} + +/* + * + */ + +function readExportAs (startPos, endPos) { + let ch = source.charCodeAt(pos); + let ls = startPos, le = endPos; + if (ch === 97 /*a*/) { + pos += 2; + ch = commentWhitespace(true); + startPos = pos; + readToWsOrPunctuator(ch); + endPos = pos; + ch = commentWhitespace(true); + } + if (pos !== startPos) + addExport(startPos, endPos, ls, le); + return ch; +} + +function readImportString (ss, ch) { + const startPos = pos + 1; + if (ch === 39/*'*/ || ch === 34/*"*/) { + stringLiteral(ch); + } + else { + syntaxError(); + return; + } + const impt = addImport(ss, startPos, pos, -1); + readName(impt); + pos++; + ch = commentWhitespace(false); + if (ch !== 97/*a*/ || !source.startsWith('ssert', pos + 1)) { + pos--; + return; + } + const assertIndex = pos; + + pos += 6; + ch = commentWhitespace(true); + if (ch !== 123/*{*/) { + pos = assertIndex; + return; + } + const assertStart = pos; + do { + pos++; + ch = commentWhitespace(true); + if (ch === 39/*'*/ || ch === 34/*"*/) { + stringLiteral(ch); + pos++; + ch = commentWhitespace(true); + } + else { + ch = readToWsOrPunctuator(ch); + } + if (ch !== 58/*:*/) { + pos = assertIndex; + return; + } + pos++; + ch = commentWhitespace(true); + if (ch === 39/*'*/ || ch === 34/*"*/) { + stringLiteral(ch); + } + else { + pos = assertIndex; + return; + } + pos++; + ch = commentWhitespace(true); + if (ch === 44/*,*/) { + pos++; + ch = commentWhitespace(true); + if (ch === 125/*}*/) + break; + continue; + } + if (ch === 125/*}*/) + break; + pos = assertIndex; + return; + } while (true); + impt.a = assertStart; + impt.se = pos + 1; +} + +function commentWhitespace (br) { + let ch; + do { + ch = source.charCodeAt(pos); + if (ch === 47/*/*/) { + const next_ch = source.charCodeAt(pos + 1); + if (next_ch === 47/*/*/) + lineComment(); + else if (next_ch === 42/***/) + blockComment(br); + else + return ch; + } + else if (br ? !isBrOrWs(ch): !isWsNotBr(ch)) { + return ch; + } + } while (pos++ < end); + return ch; +} + +function templateString () { + while (pos++ < end) { + const ch = source.charCodeAt(pos); + if (ch === 36/*$*/ && source.charCodeAt(pos + 1) === 123/*{*/) { + pos++; + templateStack[templateStackDepth++] = templateDepth; + templateDepth = ++openTokenDepth; + return; + } + if (ch === 96/*`*/) + return; + if (ch === 92/*\*/) + pos++; + } + syntaxError(); +} + +function blockComment (br) { + pos++; + while (pos++ < end) { + const ch = source.charCodeAt(pos); + if (!br && isBr(ch)) + return; + if (ch === 42/***/ && source.charCodeAt(pos + 1) === 47/*/*/) { + pos++; + return; + } + } +} + +function lineComment () { + while (pos++ < end) { + const ch = source.charCodeAt(pos); + if (ch === 10/*\n*/ || ch === 13/*\r*/) + return; + } +} + +function stringLiteral (quote) { + while (pos++ < end) { + let ch = source.charCodeAt(pos); + if (ch === quote) + return; + if (ch === 92/*\*/) { + ch = source.charCodeAt(++pos); + if (ch === 13/*\r*/ && source.charCodeAt(pos + 1) === 10/*\n*/) + pos++; + } + else if (isBr(ch)) + break; + } + syntaxError(); +} + +function regexCharacterClass () { + while (pos++ < end) { + let ch = source.charCodeAt(pos); + if (ch === 93/*]*/) + return ch; + if (ch === 92/*\*/) + pos++; + else if (ch === 10/*\n*/ || ch === 13/*\r*/) + break; + } + syntaxError(); +} + +function regularExpression () { + while (pos++ < end) { + let ch = source.charCodeAt(pos); + if (ch === 47/*/*/) + return; + if (ch === 91/*[*/) + ch = regexCharacterClass(); + else if (ch === 92/*\*/) + pos++; + else if (ch === 10/*\n*/ || ch === 13/*\r*/) + break; + } + syntaxError(); +} + +function readToWsOrPunctuator (ch) { + do { + if (isBrOrWs(ch) || isPunctuator(ch)) + return ch; + } while (ch = source.charCodeAt(++pos)); + return ch; +} + +// Note: non-asii BR and whitespace checks omitted for perf / footprint +// if there is a significant user need this can be reconsidered +function isBr (c) { + return c === 13/*\r*/ || c === 10/*\n*/; +} + +function isWsNotBr (c) { + return c === 9 || c === 11 || c === 12 || c === 32 || c === 160; +} + +function isBrOrWs (c) { + return c > 8 && c < 14 || c === 32 || c === 160; +} + +function isBrOrWsOrPunctuatorNotDot (c) { + return c > 8 && c < 14 || c === 32 || c === 160 || isPunctuator(c) && c !== 46/*.*/; +} + +function keywordStart (pos) { + return pos === 0 || isBrOrWsOrPunctuatorNotDot(source.charCodeAt(pos - 1)); +} + +function readPrecedingKeyword (pos, match) { + if (pos < match.length - 1) + return false; + return source.startsWith(match, pos - match.length + 1) && (pos === 0 || isBrOrWsOrPunctuatorNotDot(source.charCodeAt(pos - match.length))); +} + +function readPrecedingKeyword1 (pos, ch) { + return source.charCodeAt(pos) === ch && (pos === 0 || isBrOrWsOrPunctuatorNotDot(source.charCodeAt(pos - 1))); +} + +// Detects one of case, debugger, delete, do, else, in, instanceof, new, +// return, throw, typeof, void, yield, await +function isExpressionKeyword (pos) { + switch (source.charCodeAt(pos)) { + case 100/*d*/: + switch (source.charCodeAt(pos - 1)) { + case 105/*i*/: + // void + return readPrecedingKeyword(pos - 2, 'vo'); + case 108/*l*/: + // yield + return readPrecedingKeyword(pos - 2, 'yie'); + default: + return false; + } + case 101/*e*/: + switch (source.charCodeAt(pos - 1)) { + case 115/*s*/: + switch (source.charCodeAt(pos - 2)) { + case 108/*l*/: + // else + return readPrecedingKeyword1(pos - 3, 101/*e*/); + case 97/*a*/: + // case + return readPrecedingKeyword1(pos - 3, 99/*c*/); + default: + return false; + } + case 116/*t*/: + // delete + return readPrecedingKeyword(pos - 2, 'dele'); + default: + return false; + } + case 102/*f*/: + if (source.charCodeAt(pos - 1) !== 111/*o*/ || source.charCodeAt(pos - 2) !== 101/*e*/) + return false; + switch (source.charCodeAt(pos - 3)) { + case 99/*c*/: + // instanceof + return readPrecedingKeyword(pos - 4, 'instan'); + case 112/*p*/: + // typeof + return readPrecedingKeyword(pos - 4, 'ty'); + default: + return false; + } + case 110/*n*/: + // in, return + return readPrecedingKeyword1(pos - 1, 105/*i*/) || readPrecedingKeyword(pos - 1, 'retur'); + case 111/*o*/: + // do + return readPrecedingKeyword1(pos - 1, 100/*d*/); + case 114/*r*/: + // debugger + return readPrecedingKeyword(pos - 1, 'debugge'); + case 116/*t*/: + // await + return readPrecedingKeyword(pos - 1, 'awai'); + case 119/*w*/: + switch (source.charCodeAt(pos - 1)) { + case 101/*e*/: + // new + return readPrecedingKeyword1(pos - 2, 110/*n*/); + case 111/*o*/: + // throw + return readPrecedingKeyword(pos - 2, 'thr'); + default: + return false; + } + } + return false; +} + +function isParenKeyword (curPos) { + return source.charCodeAt(curPos) === 101/*e*/ && source.startsWith('whil', curPos - 4) || + source.charCodeAt(curPos) === 114/*r*/ && source.startsWith('fo', curPos - 2) || + source.charCodeAt(curPos - 1) === 105/*i*/ && source.charCodeAt(curPos) === 102/*f*/; +} + +function isPunctuator (ch) { + // 23 possible punctuator endings: !%&()*+,-./:;<=>?[]^{}|~ + return ch === 33/*!*/ || ch === 37/*%*/ || ch === 38/*&*/ || + ch > 39 && ch < 48 || ch > 57 && ch < 64 || + ch === 91/*[*/ || ch === 93/*]*/ || ch === 94/*^*/ || + ch > 122 && ch < 127; +} + +function isExpressionPunctuator (ch) { + // 20 possible expression endings: !%&(*+,-.:;<=>?[^{|~ + return ch === 33/*!*/ || ch === 37/*%*/ || ch === 38/*&*/ || + ch > 39 && ch < 47 && ch !== 41 || ch > 57 && ch < 64 || + ch === 91/*[*/ || ch === 94/*^*/ || ch > 122 && ch < 127 && ch !== 125/*}*/; +} + +function isExpressionTerminator (curPos) { + // detects: + // => ; ) finally catch else + // as all of these followed by a { will indicate a statement brace + switch (source.charCodeAt(curPos)) { + case 62/*>*/: + return source.charCodeAt(curPos - 1) === 61/*=*/; + case 59/*;*/: + case 41/*)*/: + return true; + case 104/*h*/: + return source.startsWith('catc', curPos - 4); + case 121/*y*/: + return source.startsWith('finall', curPos - 6); + case 101/*e*/: + return source.startsWith('els', curPos - 3); + } + return false; +} + +function syntaxError () { + throw Object.assign(new Error(`Parse error ${name}:${source.slice(0, pos).split('\n').length}:${pos - source.lastIndexOf('\n', pos - 1)}`), { idx: pos }); +} \ No newline at end of file -- cgit v1.2.3