cc @ericvicenti @hramos

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Note this should be noted as a breaking change in the next release, unless it's fixed internally by then.

Although it is possible to avoid a breaking change, I do like the idea of FlowExpectedError.

It is a shame we need to update the flow config in everybody's app for suppression that only happens within RN.

@ericvicenti this would still be a breaking change actually, as long as "site=react_native_oss" in Flow suppression comments exists in the code base.

Until Flow supports nested flowconfig's (which I'm not sure is even on the Flow team's roadmap) or a very complete react-native flow interface definition is added to flow-typed, which would be pretty difficult, and probably should be auto-generated in order to keep completeness and for it stay up to date, this is just something that we have to deal with. Adding to flow-typed would actually let projects using Flow and depending on RN to actually ignore all of node_modules/react-native in their flowconfig.

Awesome, thanks @skevy!

$FlowExpectedError should be widely beneficial because it let's people write their own flow tests like https://github.com/facebook/react-native/blob/master/Libraries/Experimental/__flowtests__/FlatList-flowtest.js

Thanks @skevy!

@sahrens totally agree that this is a useful feature! Gonna start doing this myself :p

It's unfortunate that it's a breaking change. But it is what it is. Just the state of the world at the moment.

Awesome, thanks @skevy!