Add support for Flow TypedArgument in no-unsed-prop-types rule

[jseminck]

While working on #1393 I noticed that no-unused-prop-types rule supports way more cases than prop-types rule already supports.

Since we would release Flow 0.53 support in the next release for the prop-types rule, I felt it wouldn't be really complete if we supported the Flow TypedArgument syntax for this rule either.

Since #1393 will take a bit more time for me to complete, I figured that an additional extra small PR to add this support to this rule would be very useful.

The code is 100% copy-paste from the prop-types rule. The goal for #1393 is to actually eliminate that duplication.

[ljharb]

Seems legit

[yannickcr]

Does a release with #1376 and this one are enough to get a good Flow 53 support ? Or is it better to wait for #1393 ?

(I do not use Flow so I don't really know what is our current support status)

[jseminck]

#1393 is this PR.

I created the issue because in addition we should merge the code for prop-types and no-unused-prop-types. The code is currently 80% the same, but some cases are supported in one rule and not the other.

I think this PR + #1377 cover the new Flow syntax for these two rules.

Edit: There's also another rule related to props checking: default-props-match-prop-types. That rule doesn't even support the <void, Props, void> (<= Flow 0.53) syntax at the moment. Ideally we should add support for the syntax for that rule as well, but no one has asked about it so far.

There's also some other Flow related bug fixes in the current open PR list. #1400 and #1390

I also don't use Flow so can't really be certain. What I could do is test out on a Flow open-source code base that I have contributed a few times to to test if everything is fine once everything has landed in master. It's not a big code-base but it's better than nothing. 😄

[yannickcr]

Ok, then after merging theses PR I will publish a pre-release version for testing purpose.

[jseminck]

Great. Perhaps @EvHaus can also test it? I think he's also working with a (big?) Flow code base.

I can try it on https://github.com/CompuIves/codesandbox-client/ (uses new Flow syntax) and https://github.com/bvaughn/babel-repl (uses normal Flow syntax, no TypedArguments)

[EvHaus]

Yeah, I'd love to test a pre-release of this. I'm sitting on hundreds of Flow-typed components :)

[yannickcr]

I just published 7.4.0-rc.0 (release notes). You can install it with npm install eslint-plugin-react@next.

Feel free to report any issue 😃

[techieshark]

@yannickcr thanks, just ran into this problem (types in flow, not proptypes), googled it and found this issue, saw your comment and updated to eslint-plugin-react@next and that problem seemed to go away. By no means thorough testing but I appreciate not having that error anymore!

[EvHaus]

Both no-unused-prop-types and prop-types working wonderfully on eslint-plugin-react@7.4.0-rc.0 using flow@0.54.0 for me across all my code bases. Didn't need to change a single thing. Nicely done everyone!

@jseminck ❤️