IE 11 + [email protected]： String.prototype.split doesn't work correctly

[bloody-ux]

With core-js 3.6.1: '/home/sessionCheck.json'.split(//+/) will get:

The correct result should be:

[zloirock]

How do you import core-js?

[randym]

@zloirock @bloody-ux

I was able to reproduce this in a browserify/babelify build when @babel/preset-env useBuiltIns is configured to 'usage' which adds the following core-js polyfills to the module doing a split with a regular expression.

  es.regexp.exec { "ie":"11" }
  es.string.split { "edge":"18", "ie":"11" }

In the short term, there where two ways I was able to work around this.

1. Downgrade core-js to 3.5.0

2. set useBuiltIns to 'entry' (assuming you are not importing core-js manually)

[zloirock]

@randym I tested this case too. Could you add a reproducible example?

[randym]

@zloirock I've setup a repo to start pulling in the polyfills that my client's app used and see if I can reproduce it in a 'bare-ish' bones example.

Just pulling in

es.regexp.exec { "ie":"11" }
es.string.split { "edge":"18", "ie":"11" }

In isolation was not enough to reproduce the problem.

I've sent both of you collaborator invites with the understanding that @bloody-ux and I bear the burden of reproduction.

[zloirock]

Still the same with the example from your repo:

I have no ideas about the order which could cause the problem, so waiting for that.

Seems it's caused by #732, I thought about possible problems like this, but I didn't find them.

[asapach]

I was able to reduce the problem to:

import 'core-js/stable/string/split';

Once the regexp polyfills are included the problem goes away:

import 'core-js/stable/regexp';

[zloirock]

@asapach I can't find the problem in the code, however, that makes sense, I'll check it in IE11 little later. But in the @randym issue es.string.split injected only with es.regexp.exec.

[zloirock]

Could you check it with this patch?

[asapach]

I've checked the fix and it does seem to address the problem in my use case.

[randym]

confirmed fix @zloirock / @asapach - thanks

[albert-asin]

I have the same problem with IE11 + core-js 3.6.5 + D3 + angular 9
I cannot downgrade to core-js 3.5.0
so, I found a workaround

I replaced the following line in my polyfills.ts
import 'core-js';

to
import 'core-js/stable/array';
import 'core-js/stable/date';
import 'core-js/stable/function';
import 'core-js/stable/map';
import 'core-js/stable/math';
import 'core-js/stable/number';
import 'core-js/stable/object';
import 'core-js/stable/parse-float';
import 'core-js/stable/parse-int';
// import 'core-js/stable/regexp';
import 'core-js/stable/set';
// import 'core-js/stable/string';
import 'core-js/stable/symbol';
import 'core-js/stable/weak-map';

Note that the imports regexp and string are commented.

So when your application needs to do a split it's using the native function of the browser instead of the split function in core-js

I hope this can help someone

[artem1]

Same problem on core-js 3.8.1
@babel/preset-env with ie11 and useBuiltin: usage

And also can't repro without all code...

This regexp in superagent lib (parse http request headers), can't patch in lib ((

[artem1]

downgrade to core-js 3.5.0 helps (no es.string.split module in bundle now)

[Jokero]

With downgraded version I get an error related to promise: "Object doesn't support property or method 'allSettled'"