Material-ui: isFragment is not exported by node_modules/react-is/index.js

[kevinvugts]

• [ ] The issue is present in the latest release.
• [X] I have searched the issues of this repository and believe that this is not a duplicate.

Current Behavior 😯

When trying to generate a build with rollup the above error is thrown:

isFragment is not exported by node_modules/react-is/index.js

Expected Behavior 🤔

It should build succesfully.

Steps to Reproduce 🕹

Build with rollup and you'll see the result..

Your Environment 🌎

| Tech | Version |
| ----------- | ------- |
| Material-UI | v4.6.0 |
| React | v16.4.1 |
| Browser | chrome |
| TypeScript | mix |
| Material-UI Lab | v 4.0.0-alpha.34 |

Screenshot

[oliviertassinari]

This was fixed in the lastest version.

[oliviertassinari]

I have this fix in mind #18551

[oliviertassinari]

isFragment is exported in https://unpkg.com/browse/[email protected]/cjs/react-is.development.js, we should be fine.

[kevinvugts]

This was fixed in the lastest version.

I upgraded to the latest material-ui/lab version but it did not fix it for me.

Update - it was in my rollup config..

[chirhotec]

I'm still running into this issue using material-ui core 4.8.3 and lab 4.0.0-alpha.39

[!] Error: 'isFragment' is not exported by node_modules/react-is/index.js
https://github.com/rollup/rollup/wiki/Troubleshooting#name-is-not-exported-by-module
node_modules/@material-ui/core/esm/Tabs/Tabs.js (5:9)
3: import _defineProperty from "@babel/runtime/helpers/esm/defineProperty";
4: import React from 'react';
5: import { isFragment } from 'react-is';
            ^
6: import PropTypes from 'prop-types';
7: import clsx from 'clsx';

@kevinvugts Is this a rollup problem? Suggestions on what to change? I've just started working with that, using the default config generated by create-react-library, so I'm not really sure how to fix it.

EDIT: Fixed by adding to the rollup commonjs section:

    commonjs({
      include: 'node_modules/**',
      namedExports: {
        'node_modules/react-is/index.js': ['isFragment', 'ForwardRef']
      }
    })

[oze4]

@kevinvugts what was wrong with your rollup config?