regenerator: Detection for accidentalStrictMode results in failures on some platforms

For anyone who struggled with this problem: Run this code before regenerator-runtime executes

globalThis.regeneratorRuntime = undefined

I recently became aware of a very clever globalThis polyfill that works in all JS implementations, without ever resorting to using the Function constructor: https://mathiasbynens.be/notes/globalthis (by @mathiasbynens).

Here’s another project where I implemented this polyfill, and it’s worked perfectly so far: https://github.com/apollographql/invariant-packages/pull/53

For historical reasons, I’ve tried to keep regenerator-runtime/runtime.js runnable as a single script (rather than a CommonJS or ESM module), so I think we would need to inline the https://www.npmjs.com/package/@ungap/global-this implementation, rather than importing it, but it’s very short.

Any objections to moving forward with that approach?

I’m having this problem also. I’m working on a healthcare app and allowing unsafe-eval in the CSP is not an option. I can disable strict mode in the rollup options of my library but this seems like a bad workaround. I feel like strict mode should be able to work, and we shouldn’t have to give up the performance optimizations and error detection benefits.

I think this needs to be revisited. I’m also using toolchains such as create-react-app and tsdx and seeing failures. Both projects are closing issues related to this because they argue it’s the problem of regenerator-runtime. Unfortunately our project will fail compliance without a strict CSP, and I’m not sure how to disable strict mode from create-react-app. And as Mozilla noted in regards to this issue, disabling strict mode isn’t something anyone is keen to do.

I thought I could resolve the issue by using a yarn resolution to force an older version that doesn’t exhibit this issue, but unfortunately that doesn’t work either because multiple other libraries we depend on come pre-bundled with a later version of regenerator-runtime. Seems like the only way we will be able to get CSP working is if an update resolves the issue, and libraries start taking in the update. 😕

I am having this same problem; using strict CSP with no unsafe-eval, i end up in the catch block for some reason. I am not entirely clear what is causing me to be in “accidentalStrictMode”. Am using the react toolchain based on create-react-app. Am attempting to downgrade this for the time being…