source: imaps-frontend/node_modules/regexp.prototype.flags/shim.js

'use strict';

var supportsDescriptors = require('define-properties').supportsDescriptors;
var getPolyfill = require('./polyfill');
var gOPD = Object.getOwnPropertyDescriptor;
var defineProperty = Object.defineProperty;
var TypeErr = TypeError;
var getProto = Object.getPrototypeOf;
var regex = /a/;

module.exports = function shimFlags() {
        if (!supportsDescriptors || !getProto) {
                throw new TypeErr('RegExp.prototype.flags requires a true ES5 environment that supports property descriptors');
        }
        var polyfill = getPolyfill();
        var proto = getProto(regex);
        var descriptor = gOPD(proto, 'flags');
        if (!descriptor || descriptor.get !== polyfill) {
                defineProperty(proto, 'flags', {
                        configurable: true,
                        enumerable: false,
                        get: polyfill
                });
        }
        return polyfill;
};