Module not found: Can't resolve '@babel/runtime/helpers/builtin/assertThisInitialized' in 'C:\Users\usr\proj\node_modules\@material-ui\core\ButtonBase'

[charlie632]

I just installed Material-UI and copied an example from the docs and encoutered this error. I looked in my node_modules folder and the file for "assertThisInitialized" is in there, but the compiler can't seem to find it.

[calebj0seph]

This seems to be caused by the v7.0.0-beta.56 release of @babel/runtime, which split part of the package up into @babel/runtime-corejs2. Material-UI lists ^7.0.0-beta.42 as the version range for @babel/runtime, which will select the latest release v7.0.0-beta.56, causing this issue.

For a quick workaround, you can try npm install --save-exact @babel/[email protected] if using npm or yarn add @babel/[email protected] --exact if using Yarn.

[calebj0seph]

Caused by babel/babel#8266.

[charlie632]

Solved! Thanks a lot!

[nareshbhatia]

Ran into this issue just now. @calebj0seph, thanks for the workaround. However, I think this issue should be kept open for a permanent fix.

cc. @oliviertassinari, @mbrookes

[charlie632]

Reopening

[oliviertassinari]

@nareshbhatia It should be OK with v1.4.3

[oliviertassinari]

It's a duplicate of #12408.

[calebj0seph]

@nareshbhatia @charlie632 This has already fixed in #12409, so you can keep this closed 🙂

[nareshbhatia]

@oliviertassinari, just saw your commit. Thanks for the amazing response time.

[oliviertassinari]

@nareshbhatia We had almost no star for 10 hours. It was the sign something was really wrong. 20 👍 on a issue in less than 10 hours. I have never seen that here before.

[nareshbhatia]

@oliviertassinari amazing tips on how to monitor a repo!