core-js/internals/regexp-flags-detection.js

Standard library

'use strict';
var globalThis = require('../internals/global-this');
var fails = require('../internals/fails');

// babel-minify and Closure Compiler transpiles RegExp('.', 'd') -> /./d and it causes SyntaxError
var RegExp = globalThis.RegExp;

var FLAGS_GETTER_IS_CORRECT = !fails(function () {
  var INDICES_SUPPORT = true;
  try {
    RegExp('.', 'd');
  } catch (error) {
    INDICES_SUPPORT = false;
  }

  var O = {};
  // modern V8 bug
  var calls = '';
  var expected = INDICES_SUPPORT ? 'dgimsy' : 'gimsy';

  var addGetter = function (key, chr) {
    // eslint-disable-next-line es/no-object-defineproperty -- safe
    Object.defineProperty(O, key, { get: function () {
      calls += chr;
      return true;
    } });
  };

  var pairs = {
    dotAll: 's',
    global: 'g',
    ignoreCase: 'i',
    multiline: 'm',
    sticky: 'y'
  };

  if (INDICES_SUPPORT) pairs.hasIndices = 'd';

  for (var key in pairs) addGetter(key, pairs[key]);

  // eslint-disable-next-line es/no-object-getownpropertydescriptor -- safe
  var result = Object.getOwnPropertyDescriptor(RegExp.prototype, 'flags').get.call(O);

  return result !== expected || calls !== expected;
});

module.exports = { correct: FLAGS_GETTER_IS_CORRECT };