Yellow Box for react-dom

[keyz]

This is a port of React Native's Yellow Box to react-dom. It's also similar to our internal ErrorMessageConsole module at Facebook.

It requires facebook/fbjs#165 which passes warning info from warning(...) to __showWarning(...) (the new global hook installed by react-dom).

A demo can be found here: https://jsfiddle.net/keyanzhang/mmupy3zh/15/embedded/result/. There's no fancy styling since we want to keep this component as simple as possible.

Thanks for reviewing! @spicyj

[sophiebits]

This depends on a later commit. :\

[keyz]

Oops, sorry didn't notice that :|

[keyz]

Just rebased and updated. https://jsfiddle.net/keyanzhang/mmupy3zh/15/embedded/result/

[addyosmani]

Beyond another rebase, is there further work to be done here before this lands? :)

[aweary]

@addyosmani it depends on facebook/fbjs#165 (which itself requires some rebasing), and it will also need to be implemented in ReactDOMFiber.

It's not clear what the status is here since it's been sitting here for so long without review, maybe @spicyj or @gaearon can clarify whether this is something that we still want to do.

[acdlite]

I believe this is on pause until we figure out a good public API for exposing hooks to warning and error reporting. @bvaughn built a version we use internally at Facebook that will inform what we do in open source.

[bvaughn]

There was also a related exploration on #8861 but as Andrew said, the team decided to put yellow box on hold for now in favor of higher-priority v16 stuff. We'll revisit it soon hopefully. 😄

[aweary]

Thanks for clarifying @acdlite @bvaughn! Should we close this then if it's not currently slated to be merged and isn't likely the implementation that will be used?

[bvaughn]

I think it's okay to close this PR for now. We may still end up using this as a starting point for whatever we do merge, but it's unlikely to be merged as-is.

[aweary]

@addyosmani thanks for bringing this to our attention again!