basant307/AI_Governance_Project

1/*2  Copyright (C) 2013 Yusuke Suzuki <utatane.tea@gmail.com>3 4  Redistribution and use in source and binary forms, with or without5  modification, are permitted provided that the following conditions are met:6 7    * Redistributions of source code must retain the above copyright8      notice, this list of conditions and the following disclaimer.9    * Redistributions in binary form must reproduce the above copyright10      notice, this list of conditions and the following disclaimer in the11      documentation and/or other materials provided with the distribution.12 13  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"14  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE15  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE16  ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY17  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES18  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;19  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND20  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT21  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF22  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.23*/24 25(function () {26    'use strict';27 28    var code = require('./code');29 30    function isStrictModeReservedWordES6(id) {31        switch (id) {32        case 'implements':33        case 'interface':34        case 'package':35        case 'private':36        case 'protected':37        case 'public':38        case 'static':39        case 'let':40            return true;41        default:42            return false;43        }44    }45 46    function isKeywordES5(id, strict) {47        // yield should not be treated as keyword under non-strict mode.48        if (!strict && id === 'yield') {49            return false;50        }51        return isKeywordES6(id, strict);52    }53 54    function isKeywordES6(id, strict) {55        if (strict && isStrictModeReservedWordES6(id)) {56            return true;57        }58 59        switch (id.length) {60        case 2:61            return (id === 'if') || (id === 'in') || (id === 'do');62        case 3:63            return (id === 'var') || (id === 'for') || (id === 'new') || (id === 'try');64        case 4:65            return (id === 'this') || (id === 'else') || (id === 'case') ||66                (id === 'void') || (id === 'with') || (id === 'enum');67        case 5:68            return (id === 'while') || (id === 'break') || (id === 'catch') ||69                (id === 'throw') || (id === 'const') || (id === 'yield') ||70                (id === 'class') || (id === 'super');71        case 6:72            return (id === 'return') || (id === 'typeof') || (id === 'delete') ||73                (id === 'switch') || (id === 'export') || (id === 'import');74        case 7:75            return (id === 'default') || (id === 'finally') || (id === 'extends');76        case 8:77            return (id === 'function') || (id === 'continue') || (id === 'debugger');78        case 10:79            return (id === 'instanceof');80        default:81            return false;82        }83    }84 85    function isReservedWordES5(id, strict) {86        return id === 'null' || id === 'true' || id === 'false' || isKeywordES5(id, strict);87    }88 89    function isReservedWordES6(id, strict) {90        return id === 'null' || id === 'true' || id === 'false' || isKeywordES6(id, strict);91    }92 93    function isRestrictedWord(id) {94        return id === 'eval' || id === 'arguments';95    }96 97    function isIdentifierNameES5(id) {98        var i, iz, ch;99 100        if (id.length === 0) { return false; }101 102        ch = id.charCodeAt(0);103        if (!code.isIdentifierStartES5(ch)) {104            return false;105        }106 107        for (i = 1, iz = id.length; i < iz; ++i) {108            ch = id.charCodeAt(i);109            if (!code.isIdentifierPartES5(ch)) {110                return false;111            }112        }113        return true;114    }115 116    function decodeUtf16(lead, trail) {117        return (lead - 0xD800) * 0x400 + (trail - 0xDC00) + 0x10000;118    }119 120    function isIdentifierNameES6(id) {121        var i, iz, ch, lowCh, check;122 123        if (id.length === 0) { return false; }124 125        check = code.isIdentifierStartES6;126        for (i = 0, iz = id.length; i < iz; ++i) {127            ch = id.charCodeAt(i);128            if (0xD800 <= ch && ch <= 0xDBFF) {129                ++i;130                if (i >= iz) { return false; }131                lowCh = id.charCodeAt(i);132                if (!(0xDC00 <= lowCh && lowCh <= 0xDFFF)) {133                    return false;134                }135                ch = decodeUtf16(ch, lowCh);136            }137            if (!check(ch)) {138                return false;139            }140            check = code.isIdentifierPartES6;141        }142        return true;143    }144 145    function isIdentifierES5(id, strict) {146        return isIdentifierNameES5(id) && !isReservedWordES5(id, strict);147    }148 149    function isIdentifierES6(id, strict) {150        return isIdentifierNameES6(id) && !isReservedWordES6(id, strict);151    }152 153    module.exports = {154        isKeywordES5: isKeywordES5,155        isKeywordES6: isKeywordES6,156        isReservedWordES5: isReservedWordES5,157        isReservedWordES6: isReservedWordES6,158        isRestrictedWord: isRestrictedWord,159        isIdentifierNameES5: isIdentifierNameES5,160        isIdentifierNameES6: isIdentifierNameES6,161        isIdentifierES5: isIdentifierES5,162        isIdentifierES6: isIdentifierES6163    };164}());165/* vim: set sw=4 ts=4 et tw=80 : */166