source: node_modules/minimist/index.js

'use strict';

function hasKey(obj, keys) {
        var o = obj;
        keys.slice(0, -1).forEach(function (key) {
                o = o[key] || {};
        });

        var key = keys[keys.length - 1];
        return key in o;
}

function isNumber(x) {
        if (typeof x === 'number') { return true; }
        if ((/^0x[0-9a-f]+$/i).test(x)) { return true; }
        return (/^[-+]?(?:\d+(?:\.\d*)?|\.\d+)(e[-+]?\d+)?$/).test(x);
}

function isConstructorOrProto(obj, key) {
        return (key === 'constructor' && typeof obj[key] === 'function') || key === '__proto__';
}

module.exports = function (args, opts) {
        if (!opts) { opts = {}; }

        var flags = {
                bools: {},
                strings: {},
                unknownFn: null,
        };

        if (typeof opts.unknown === 'function') {
                flags.unknownFn = opts.unknown;
        }

        if (typeof opts.boolean === 'boolean' && opts.boolean) {
                flags.allBools = true;
        } else {
                [].concat(opts.boolean).filter(Boolean).forEach(function (key) {
                        flags.bools[key] = true;
                });
        }

        var aliases = {};

        function aliasIsBoolean(key) {
                return aliases[key].some(function (x) {
                        return flags.bools[x];
                });
        }

        Object.keys(opts.alias || {}).forEach(function (key) {
                aliases[key] = [].concat(opts.alias[key]);
                aliases[key].forEach(function (x) {
                        aliases[x] = [key].concat(aliases[key].filter(function (y) {
                                return x !== y;
                        }));
                });
        });

        [].concat(opts.string).filter(Boolean).forEach(function (key) {
                flags.strings[key] = true;
                if (aliases[key]) {
                        [].concat(aliases[key]).forEach(function (k) {
                                flags.strings[k] = true;
                        });
                }
        });

        var defaults = opts.default || {};

        var argv = { _: [] };

        function argDefined(key, arg) {
                return (flags.allBools && (/^--[^=]+$/).test(arg))
                        || flags.strings[key]
                        || flags.bools[key]
                        || aliases[key];
        }

        function setKey(obj, keys, value) {
                var o = obj;
                for (var i = 0; i < keys.length - 1; i++) {
                        var key = keys[i];
                        if (isConstructorOrProto(o, key)) { return; }
                        if (o[key] === undefined) { o[key] = {}; }
                        if (
                                o[key] === Object.prototype
                                || o[key] === Number.prototype
                                || o[key] === String.prototype
                        ) {
                                o[key] = {};
                        }
                        if (o[key] === Array.prototype) { o[key] = []; }
                        o = o[key];
                }

                var lastKey = keys[keys.length - 1];
                if (isConstructorOrProto(o, lastKey)) { return; }
                if (
                        o === Object.prototype
                        || o === Number.prototype
                        || o === String.prototype
                ) {
                        o = {};
                }
                if (o === Array.prototype) { o = []; }
                if (o[lastKey] === undefined || flags.bools[lastKey] || typeof o[lastKey] === 'boolean') {
                        o[lastKey] = value;
                } else if (Array.isArray(o[lastKey])) {
                        o[lastKey].push(value);
                } else {
                        o[lastKey] = [o[lastKey], value];
                }
        }

        function setArg(key, val, arg) {
                if (arg && flags.unknownFn && !argDefined(key, arg)) {
                        if (flags.unknownFn(arg) === false) { return; }
                }

                var value = !flags.strings[key] && isNumber(val)
                        ? Number(val)
                        : val;
                setKey(argv, key.split('.'), value);

                (aliases[key] || []).forEach(function (x) {
                        setKey(argv, x.split('.'), value);
                });
        }

        Object.keys(flags.bools).forEach(function (key) {
                setArg(key, defaults[key] === undefined ? false : defaults[key]);
        });

        var notFlags = [];

        if (args.indexOf('--') !== -1) {
                notFlags = args.slice(args.indexOf('--') + 1);
                args = args.slice(0, args.indexOf('--'));
        }

        for (var i = 0; i < args.length; i++) {
                var arg = args[i];
                var key;
                var next;

                if ((/^--.+=/).test(arg)) {
                        // Using [\s\S] instead of . because js doesn't support the
                        // 'dotall' regex modifier. See:
                        // http://stackoverflow.com/a/1068308/13216
                        var m = arg.match(/^--([^=]+)=([\s\S]*)$/);
                        key = m[1];
                        var value = m[2];
                        if (flags.bools[key]) {
                                value = value !== 'false';
                        }
                        setArg(key, value, arg);
                } else if ((/^--no-.+/).test(arg)) {
                        key = arg.match(/^--no-(.+)/)[1];
                        setArg(key, false, arg);
                } else if ((/^--.+/).test(arg)) {
                        key = arg.match(/^--(.+)/)[1];
                        next = args[i + 1];
                        if (
                                next !== undefined
                                && !(/^(-|--)[^-]/).test(next)
                                && !flags.bools[key]
                                && !flags.allBools
                                && (aliases[key] ? !aliasIsBoolean(key) : true)
                        ) {
                                setArg(key, next, arg);
                                i += 1;
                        } else if ((/^(true|false)$/).test(next)) {
                                setArg(key, next === 'true', arg);
                                i += 1;
                        } else {
                                setArg(key, flags.strings[key] ? '' : true, arg);
                        }
                } else if ((/^-[^-]+/).test(arg)) {
                        var letters = arg.slice(1, -1).split('');

                        var broken = false;
                        for (var j = 0; j < letters.length; j++) {
                                next = arg.slice(j + 2);

                                if (next === '-') {
                                        setArg(letters[j], next, arg);
                                        continue;
                                }

                                if ((/[A-Za-z]/).test(letters[j]) && next[0] === '=') {
                                        setArg(letters[j], next.slice(1), arg);
                                        broken = true;
                                        break;
                                }

                                if (
                                        (/[A-Za-z]/).test(letters[j])
                                        && (/-?\d+(\.\d*)?(e-?\d+)?$/).test(next)
                                ) {
                                        setArg(letters[j], next, arg);
                                        broken = true;
                                        break;
                                }

                                if (letters[j + 1] && letters[j + 1].match(/\W/)) {
                                        setArg(letters[j], arg.slice(j + 2), arg);
                                        broken = true;
                                        break;
                                } else {
                                        setArg(letters[j], flags.strings[letters[j]] ? '' : true, arg);
                                }
                        }

                        key = arg.slice(-1)[0];
                        if (!broken && key !== '-') {
                                if (
                                        args[i + 1]
                                        && !(/^(-|--)[^-]/).test(args[i + 1])
                                        && !flags.bools[key]
                                        && (aliases[key] ? !aliasIsBoolean(key) : true)
                                ) {
                                        setArg(key, args[i + 1], arg);
                                        i += 1;
                                } else if (args[i + 1] && (/^(true|false)$/).test(args[i + 1])) {
                                        setArg(key, args[i + 1] === 'true', arg);
                                        i += 1;
                                } else {
                                        setArg(key, flags.strings[key] ? '' : true, arg);
                                }
                        }
                } else {
                        if (!flags.unknownFn || flags.unknownFn(arg) !== false) {
                                argv._.push(flags.strings._ || !isNumber(arg) ? arg : Number(arg));
                        }
                        if (opts.stopEarly) {
                                argv._.push.apply(argv._, args.slice(i + 1));
                                break;
                        }
                }
        }

        Object.keys(defaults).forEach(function (k) {
                if (!hasKey(argv, k.split('.'))) {
                        setKey(argv, k.split('.'), defaults[k]);

                        (aliases[k] || []).forEach(function (x) {
                                setKey(argv, x.split('.'), defaults[k]);
                        });
                }
        });

        if (opts['--']) {
                argv['--'] = notFlags.slice();
        } else {
                notFlags.forEach(function (k) {
                        argv._.push(k);
                });
        }

        return argv;
};