monaco-react/demo/public/polyfill.js

if ((/bot|googlebot|crawler|spider|robot|crawling/i.test(navigator.userAgent))) {
  // https://tc39.github.io/ecma262/#sec-array.prototype.findindex
  if (!Array.prototype.findIndex) {
    Object.defineProperty(Array.prototype, 'findIndex', {
      value: function(predicate) {
       // 1. Let O be ? ToObject(this value).
        if (this == null) {
          throw new TypeError('"this" is null or not defined');
        }

        var o = Object(this);

        // 2. Let len be ? ToLength(? Get(O, "length")).
        var len = o.length >>> 0;

        // 3. If IsCallable(predicate) is false, throw a TypeError exception.
        if (typeof predicate !== 'function') {
          throw new TypeError('predicate must be a function');
        }

        // 4. If thisArg was supplied, let T be thisArg; else let T be undefined.
        var thisArg = arguments[1];

        // 5. Let k be 0.
        var k = 0;

        // 6. Repeat, while k < len
        while (k < len) {
          // a. Let Pk be ! ToString(k).
          // b. Let kValue be ? Get(O, Pk).
          // c. Let testResult be ToBoolean(? Call(predicate, T, « kValue, k, O »)).
          // d. If testResult is true, return k.
          var kValue = o[k];
          if (predicate.call(thisArg, kValue, k, o)) {
            return k;
          }
          // e. Increase k by 1.
          k++;
        }

        // 7. Return -1.
        return -1;
      },
      configurable: true,
      writable: true
    });
  }

  // https://tc39.github.io/ecma262/#sec-array.prototype.find
  if (!Array.prototype.find) {
    Object.defineProperty(Array.prototype, 'find', {
      value: function(predicate) {
       // 1. Let O be ? ToObject(this value).
        if (this == null) {
          throw new TypeError('"this" is null or not defined');
        }

        var o = Object(this);

        // 2. Let len be ? ToLength(? Get(O, "length")).
        var len = o.length >>> 0;

        // 3. If IsCallable(predicate) is false, throw a TypeError exception.
        if (typeof predicate !== 'function') {
          throw new TypeError('predicate must be a function');
        }

        // 4. If thisArg was supplied, let T be thisArg; else let T be undefined.
        var thisArg = arguments[1];

        // 5. Let k be 0.
        var k = 0;

        // 6. Repeat, while k < len
        while (k < len) {
          // a. Let Pk be ! ToString(k).
          // b. Let kValue be ? Get(O, Pk).
          // c. Let testResult be ToBoolean(? Call(predicate, T, « kValue, k, O »)).
          // d. If testResult is true, return kValue.
          var kValue = o[k];
          if (predicate.call(thisArg, kValue, k, o)) {
            return kValue;
          }
          // e. Increase k by 1.
          k++;
        }

        // 7. Return undefined.
        return undefined;
      },
      configurable: true,
      writable: true
    });
  }

  function noop() {}

  (function(){function l(){function n(a){return a?"object"===typeof a||"function"===typeof a:!1}var p=null;var g=function(a,b){function f(){}if(!n(a)||!n(b))throw new TypeError("Cannot create proxy with a non-object as target or handler");p=function(){f=function(a){throw new TypeError("Cannot perform '"+a+"' on a proxy that has been revoked");}};var e=b;b={get:null,set:null,apply:null,construct:null};for(var k in e){if(!(k in b)) noop("Proxy polyfill does not support trap '"+k+"'");b[k]=e[k]}"function"===
  typeof e&&(b.apply=e.apply.bind(e));var c=this,g=!1,q=!1;"function"===typeof a?(c=function(){var h=this&&this.constructor===c,d=Array.prototype.slice.call(arguments);f(h?"construct":"apply");return h&&b.construct?b.construct.call(this,a,d):!h&&b.apply?b.apply(a,this,d):h?(d.unshift(a),new (a.bind.apply(a,d))):a.apply(this,d)},g=!0):a instanceof Array&&(c=[],q=!0);var r=b.get?function(a){f("get");return b.get(this,a,c)}:function(a){f("get");return this[a]},v=b.set?function(a,d){f("set");b.set(this,
  a,d,c)}:function(a,b){f("set");this[a]=b},t={};Object.getOwnPropertyNames(a).forEach(function(b){if(!((g||q)&&b in c)){var d={enumerable:!!Object.getOwnPropertyDescriptor(a,b).enumerable,get:r.bind(a,b),set:v.bind(a,b)};Object.defineProperty(c,b,d);t[b]=!0}});e=!0;Object.setPrototypeOf?Object.setPrototypeOf(c,Object.getPrototypeOf(a)):c.__proto__?c.__proto__=a.__proto__:e=!1;if(b.get||!e)for(var m in a)t[m]||Object.defineProperty(c,m,{get:r.bind(a,m)});Object.seal(a);Object.seal(c);return c};g.revocable=
  function(a,b){return{proxy:new g(a,b),revoke:p}};return g};var u="undefined"!==typeof process&&"[object process]"==={}.toString.call(process)||"undefined"!==typeof navigator&&"ReactNative"===navigator.product?global:self;u.Proxy||(u.Proxy=l(),u.Proxy.revocable=u.Proxy.revocable);})()

  if (!Object.assign) {
    function assign(target, firstSource) {
      if (target === undefined || target === null) {
        throw new TypeError('Cannot convert first argument to object');
      }

      var to = Object(target);
      for (var i = 1; i < arguments.length; i++) {
        var nextSource = arguments[i];
        if (nextSource === undefined || nextSource === null) {
          continue;
        }

        var keysArray = Object.keys(Object(nextSource));
        for (var nextIndex = 0, len = keysArray.length; nextIndex < len; nextIndex++) {
          var nextKey = keysArray[nextIndex];
          var desc = Object.getOwnPropertyDescriptor(nextSource, nextKey);
          if (desc !== undefined && desc.enumerable) {
            to[nextKey] = nextSource[nextKey];
          }
        }
      }
      return to;
    }

    Object.defineProperty(Object, 'assign', {
      enumerable: false,
      configurable: true,
      writable: true,
      value: assign
    });
  }
}