Flow: Support globalThis

[goodmind]

Proposal: https://github.com/tc39/proposal-global

I don't think libdef can solve it?

Also what type top-level this should have?

[mrtnzlml]

I don't think libdef can solve it?

Seems like even global is defined simply as any value: https://github.com/facebook/flow/blob/fa89aadb55ae9bb37c71e14d7274935903d501ce/lib/core.js#L835

Are there any consequences of doing the same with globalThis or can I send a PR?

[goodmind]

I think it is wrong approach for this, there should be some declare global like TypeScript have?

[goodmind]

// `this` is undefined in module scope
this.a = 1

globalThis.a = 1

a // 1

a = 'hello'

globalThis.a // 'hello'

this.a // 'hello' or error in module scope

window.a // 'hello'

[mrtnzlml]

I understand it's not ideal but the same applies to already existing global. It would be ideal to have a better solution but I am afraid it can take quite a long time to get there. :)

[goodmind]

I'm just against typing it as any, there's already too much any in libdefs

[goodmind]

@mrtnzlml I created PR for globalThis

[mrtnzlml]

@goodmind Thank you for the PR! :) Would it be possible to do something like this even for global (to fix the any type)?