Pull in Flow-specific rules from eslint-plugin-babel

[taion]

Ref #40 (comment), babel/eslint-plugin-babel#93 (comment)

In addition to the obvious babel/flow-object-type, the following rules in eslint-plugin-babel:

• babel/array-bracket-spacing
• babel/arrow-parens

Only make a difference now when using Flow. (The latter because ESLint now supports async/await natively)

I think it would make sense to pull in those rules here – I found it confusing that the rule I wanted to get rid of spurious warnings on arrow parens when using type annotations was in eslint-plugin-babel rather than here.

[danharper]

Hm, I'm kind of unsure about the others.

I see this plugin as providing lint rules specific to Flow's syntax, whereas eslint-plugin-babel provides replacement rules to the core ESLint ones until the proposal reaches stage 4.

Since ESLint is now officially supporting simple type annotations in the AST, those 2 rules can probably be upstreamed back to ESLint.

[taion]

Ah, I didn't know that. Thanks.

[danharper]

Looks like there's a PR open for arrow-parens too :) eslint/eslint#7436

[taion]

Thanks. I opened eslint/eslint#7445 to fix array-bracket-spacing as well.