Array of objects doesnt update state

[yixe]

Hi guys, I have a simple state:

struct AppState: Equatable {
  var collection: [Single] = []
 }

struct Single: Equatable {
  var name: String
  var value: Int
 }

Whenever I send an action to update the value on an Item in the Array the value updates but isn't reflected in the view. I've tried using ForEachStore etc but nothing seems to work

[lukeredpath]

You'll need to share a bit more code to help us debug what's happening but assuming you have some kind of child reducer that operates on Single value types, remember that the child reducer is going to be mutating a copy of each element in the array. Swift arrays are not reference types, and you can demonstrate the problem more generally:

var collection: [Single] = [
  .init(name: "one", value: 1),
  .init(name: "two", value: 2)
]

var first = collection[0]
first.name = "one modified"

print(collection[0]) // => Single(name: "one", value: 1)

[lukeredpath]

@RabugenTom in my orthopaedic shoes, I stand corrected.

Then it's not immediately clear to me from the code that's been posted what is going wrong, I feel like we need to see a more complete example from OP to help.

[yixe]

@RabugenTom @lukeredpath I've been trying to debug this for a few days now, Whats bizarre to me is when you log the output of state, the value in fact changes.

case .changeValue(let index):
  state.collection[index].value +=  1
  dump(state.collection[index])  <-- outputs a Single with the +1 change
  return .none

but the view is stuck on the old value, @lukeredpath this seems to happen even when you make Single a class

Text("\(viewStore.collection[index].value)")

[yixe]

@RabugenTom Following your recommendation, It seems I might have figured out the problem
If I add my own Equatable conformance like so or make Single a class the issue occurs. Quite confusing.

  static func == (lhs: Single, rhs: Single) -> Bool {
    lhs.name == rhs.name && lhs.value == rhs.value
  }

[RabugenTom]

I would absolutely recommend to use value types for your state. This is only a logic-less container for your data so you shouldn't have to use a class if you're are not forced to by a very specific reason. The same for automatic Equatable and Hashable conformances.
Your Equatable implementation is most likely similar to the one the compiler would generate so maybe this is only the expression of a deeper issue somewhere else.
Good luck!

[konrain]

Thanks for your help