useSteps(): only update setStep when needed

[bpierre]

See https://github.com/aragon/aragon/pull/771/files/2907ecbbf266d6d866c874991de468a00fc49ddc#r282035502

[sohkai]

I wanted to avoid making this change until after #768 was merged, so we don't have too many conflicts :).

[bpierre]

Reverted :+1:

[sohkai]

Do we not need to include the reducer's updateStep because it'll never change?

[bpierre]

Exactly, setSomething from useState() and dispatch from useReducer() are both guaranteed to never update [1], and don’t need to be added to the dependencies list.

[1] Search for “guarantees” in these two sections:

https://reactjs.org/docs/hooks-reference.html#usestate
https://reactjs.org/docs/hooks-reference.html#usereducer

[sohkai]

Awesome, sounds like we've learned something new about hooks :).

Although it's still baffling why the little hacks I was doing didn't work specifically for a single case of setting the steps to 1 :(

[bpierre]

Awesome, sounds like we've learned something new about hooks :).
Yes! 👍

Although it's still baffling why the little hacks I was doing didn't work specifically for a single case of setting the steps to 1 :(

Yes and I’m not a big fan of the solution as it is… but at least the complexity stays in the hook itself, which is nice. Maybe we should move every custom hook in its own file, so that reducers, initial states etc. declared outside of the hook itself wouldn’t be in the same module than other hooks.

[sohkai]

Sounds reasonable to have a hooks/ folder to hold all the hooks