udemy-react/02/node_modules/xregexp/lib/addons/build.js

'use strict';

Object.defineProperty(exports, "__esModule", {
    value: true
});

/*!
 * XRegExp.build 4.0.0
 * <xregexp.com>
 * Steven Levithan (c) 2012-2017 MIT License
 */

exports.default = function (XRegExp) {
    var REGEX_DATA = 'xregexp';
    var subParts = /(\()(?!\?)|\\([1-9]\d*)|\\[\s\S]|\[(?:[^\\\]]|\\[\s\S])*\]/g;
    var parts = XRegExp.union([/\({{([\w$]+)}}\)|{{([\w$]+)}}/, subParts], 'g', {
        conjunction: 'or'
    });

    /**
     * Strips a leading `^` and trailing unescaped `$`, if both are present.
     *
     * @private
     * @param {String} pattern Pattern to process.
     * @returns {String} Pattern with edge anchors removed.
     */
    function deanchor(pattern) {
        // Allow any number of empty noncapturing groups before/after anchors, because regexes
        // built/generated by XRegExp sometimes include them
        var leadingAnchor = /^(?:\(\?:\))*\^/;
        var trailingAnchor = /\$(?:\(\?:\))*$/;

        if (leadingAnchor.test(pattern) && trailingAnchor.test(pattern) &&
        // Ensure that the trailing `$` isn't escaped
        trailingAnchor.test(pattern.replace(/\\[\s\S]/g, ''))) {
            return pattern.replace(leadingAnchor, '').replace(trailingAnchor, '');
        }

        return pattern;
    }

    /**
     * Converts the provided value to an XRegExp. Native RegExp flags are not preserved.
     *
     * @private
     * @param {String|RegExp} value Value to convert.
     * @param {Boolean} [addFlagX] Whether to apply the `x` flag in cases when `value` is not
     *   already a regex generated by XRegExp
     * @returns {RegExp} XRegExp object with XRegExp syntax applied.
     */
    function asXRegExp(value, addFlagX) {
        var flags = addFlagX ? 'x' : '';
        return XRegExp.isRegExp(value) ? value[REGEX_DATA] && value[REGEX_DATA].captureNames ?
        // Don't recompile, to preserve capture names
        value :
        // Recompile as XRegExp
        XRegExp(value.source, flags) :
        // Compile string as XRegExp
        XRegExp(value, flags);
    }

    function interpolate(substitution) {
        return substitution instanceof RegExp ? substitution : XRegExp.escape(substitution);
    }

    function reduceToSubpatternsObject(subpatterns, interpolated, subpatternIndex) {
        subpatterns['subpattern' + subpatternIndex] = interpolated;
        return subpatterns;
    }

    function embedSubpatternAfter(raw, subpatternIndex, rawLiterals) {
        var hasSubpattern = subpatternIndex < rawLiterals.length - 1;
        return raw + (hasSubpattern ? '{{subpattern' + subpatternIndex + '}}' : '');
    }

    /**
     * Provides tagged template literals that create regexes with XRegExp syntax and flags. The
     * provided pattern is handled as a raw string, so backslashes don't need to be escaped.
     *
     * Interpolation of strings and regexes shares the features of `XRegExp.build`. Interpolated
     * patterns are treated as atomic units when quantified, interpolated strings have their special
     * characters escaped, a leading `^` and trailing unescaped `$` are stripped from interpolated
     * regexes if both are present, and any backreferences within an interpolated regex are
     * rewritten to work within the overall pattern.
     *
     * @memberOf XRegExp
     * @param {String} [flags] Any combination of XRegExp flags.
     * @returns {Function} Handler for template literals that construct regexes with XRegExp syntax.
     * @example
     *
     * const h12 = /1[0-2]|0?[1-9]/;
     * const h24 = /2[0-3]|[01][0-9]/;
     * const hours = XRegExp.tag('x')`${h12} : | ${h24}`;
     * const minutes = /^[0-5][0-9]$/;
     * // Note that explicitly naming the 'minutes' group is required for named backreferences
     * const time = XRegExp.tag('x')`^ ${hours} (?<minutes>${minutes}) $`;
     * time.test('10:59'); // -> true
     * XRegExp.exec('10:59', time).minutes; // -> '59'
     */
    XRegExp.tag = function (flags) {
        return function (literals) {
            for (var _len = arguments.length, substitutions = Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
                substitutions[_key - 1] = arguments[_key];
            }

            var subpatterns = substitutions.map(interpolate).reduce(reduceToSubpatternsObject, {});
            var pattern = literals.raw.map(embedSubpatternAfter).join('');
            return XRegExp.build(pattern, subpatterns, flags);
        };
    };

    /**
     * Builds regexes using named subpatterns, for readability and pattern reuse. Backreferences in
     * the outer pattern and provided subpatterns are automatically renumbered to work correctly.
     * Native flags used by provided subpatterns are ignored in favor of the `flags` argument.
     *
     * @memberOf XRegExp
     * @param {String} pattern XRegExp pattern using `{{name}}` for embedded subpatterns. Allows
     *   `({{name}})` as shorthand for `(?<name>{{name}})`. Patterns cannot be embedded within
     *   character classes.
     * @param {Object} subs Lookup object for named subpatterns. Values can be strings or regexes. A
     *   leading `^` and trailing unescaped `$` are stripped from subpatterns, if both are present.
     * @param {String} [flags] Any combination of XRegExp flags.
     * @returns {RegExp} Regex with interpolated subpatterns.
     * @example
     *
     * const time = XRegExp.build('(?x)^ {{hours}} ({{minutes}}) $', {
     *   hours: XRegExp.build('{{h12}} : | {{h24}}', {
     *     h12: /1[0-2]|0?[1-9]/,
     *     h24: /2[0-3]|[01][0-9]/
     *   }, 'x'),
     *   minutes: /^[0-5][0-9]$/
     * });
     * time.test('10:59'); // -> true
     * XRegExp.exec('10:59', time).minutes; // -> '59'
     */
    XRegExp.build = function (pattern, subs, flags) {
        flags = flags || '';
        // Used with `asXRegExp` calls for `pattern` and subpatterns in `subs`, to work around how
        // some browsers convert `RegExp('\n')` to a regex that contains the literal characters `\`
        // and `n`. See more details at <https://github.com/slevithan/xregexp/pull/163>.
        var addFlagX = flags.indexOf('x') !== -1;
        var inlineFlags = /^\(\?([\w$]+)\)/.exec(pattern);
        // Add flags within a leading mode modifier to the overall pattern's flags
        if (inlineFlags) {
            flags = XRegExp._clipDuplicates(flags + inlineFlags[1]);
        }

        var data = {};
        for (var p in subs) {
            if (subs.hasOwnProperty(p)) {
                // Passing to XRegExp enables extended syntax and ensures independent validity,
                // lest an unescaped `(`, `)`, `[`, or trailing `\` breaks the `(?:)` wrapper. For
                // subpatterns provided as native regexes, it dies on octals and adds the property
                // used to hold extended regex instance data, for simplicity.
                var sub = asXRegExp(subs[p], addFlagX);
                data[p] = {
                    // Deanchoring allows embedding independently useful anchored regexes. If you
                    // really need to keep your anchors, double them (i.e., `^^...$$`).
                    pattern: deanchor(sub.source),
                    names: sub[REGEX_DATA].captureNames || []
                };
            }
        }

        // Passing to XRegExp dies on octals and ensures the outer pattern is independently valid;
        // helps keep this simple. Named captures will be put back.
        var patternAsRegex = asXRegExp(pattern, addFlagX);

        // 'Caps' is short for 'captures'
        var numCaps = 0;
        var numPriorCaps = void 0;
        var numOuterCaps = 0;
        var outerCapsMap = [0];
        var outerCapNames = patternAsRegex[REGEX_DATA].captureNames || [];
        var output = patternAsRegex.source.replace(parts, function ($0, $1, $2, $3, $4) {
            var subName = $1 || $2;
            var capName = void 0;
            var intro = void 0;
            var localCapIndex = void 0;
            // Named subpattern
            if (subName) {
                if (!data.hasOwnProperty(subName)) {
                    throw new ReferenceError('Undefined property ' + $0);
                }
                // Named subpattern was wrapped in a capturing group
                if ($1) {
                    capName = outerCapNames[numOuterCaps];
                    outerCapsMap[++numOuterCaps] = ++numCaps;
                    // If it's a named group, preserve the name. Otherwise, use the subpattern name
                    // as the capture name
                    intro = '(?<' + (capName || subName) + '>';
                } else {
                    intro = '(?:';
                }
                numPriorCaps = numCaps;
                var rewrittenSubpattern = data[subName].pattern.replace(subParts, function (match, paren, backref) {
                    // Capturing group
                    if (paren) {
                        capName = data[subName].names[numCaps - numPriorCaps];
                        ++numCaps;
                        // If the current capture has a name, preserve the name
                        if (capName) {
                            return '(?<' + capName + '>';
                        }
                        // Backreference
                    } else if (backref) {
                        localCapIndex = +backref - 1;
                        // Rewrite the backreference
                        return data[subName].names[localCapIndex] ?
                        // Need to preserve the backreference name in case using flag `n`
                        '\\k<' + data[subName].names[localCapIndex] + '>' : '\\' + (+backref + numPriorCaps);
                    }
                    return match;
                });
                return '' + intro + rewrittenSubpattern + ')';
            }
            // Capturing group
            if ($3) {
                capName = outerCapNames[numOuterCaps];
                outerCapsMap[++numOuterCaps] = ++numCaps;
                // If the current capture has a name, preserve the name
                if (capName) {
                    return '(?<' + capName + '>';
                }
                // Backreference
            } else if ($4) {
                localCapIndex = +$4 - 1;
                // Rewrite the backreference
                return outerCapNames[localCapIndex] ?
                // Need to preserve the backreference name in case using flag `n`
                '\\k<' + outerCapNames[localCapIndex] + '>' : '\\' + outerCapsMap[+$4];
            }
            return $0;
        });

        return XRegExp(output, flags);
    };
};

module.exports = exports['default'];