Ignore rest siblings for no-unused-vars

[Gudahtt]

The ignoreRestSiblings rule has been enabled for the no-unused-vars rule and the @typescript-eslint/no-unused-vars rule. This allows the use of unused variables alongside a rest operator. This pattern can be useful for excluding variables from a group that you don't want to use.

This option is already in use in the @metamask/controllers repository.

[mcmire]

I'm not sure I understand this change. Does this make it possible to do something like this:

const { foo, bar, ...rest } = someObject;

where foo and bar are allowed to be unused? If so then it's not clear to me how this is easier to use or clearer than:

const { _foo, _bar, ...rest } = someObject;

I know you said we are already using this in controllers, but is there an example of this in use?

[Gudahtt]

This is the only use I know of: /~https://github.com/MetaMask/controllers/blob/main/src/network/NetworkController.ts#L291

The alternative you showed would not work because _foo and _bar aren't the properties that we want to exclude. I think this would work though:

const { foo: _foo, bar: _bar, ...rest } = someObject;

So... not terrible 🤔 A bit verbose maybe.

[Gudahtt]

I don't feel strongly either way on this one. The workaround of aliasing the unused vars works for me.

[rekmarks]

The foo: _foo workaround seems annoying to me, I prefer we enable ignoreRestSiblings.

[mcmire]

I looked at the NetworkController example again (now available here). For some reason, my brain wasn't connecting the dots when I looked at that initially, but now I understand. This change makes sense to me and I agree with Erik that the workaround seems annoying.