Nested enum reducer error: cannot be constructed because it has no accessible initializers

[larryonoff]

Description

The case is pretty simple. The error occurs if you have nested macro-generated enum reducer (e.g. Feature1) in another macro-generated enum reducer (.e.g. Feature2).

Looks that issue occurs since Reducer macro doesn't take into account that macro-generated enum Reducers don't have inits.

Checklist

• [X] I have determined whether this bug is also reproducible in a vanilla SwiftUI project.
• [X] If possible, I've reproduced the issue using the main branch of this package.
• [X] This issue hasn't been addressed in an existing GitHub issue or discussion.

Expected behavior

No error occurs.

Actual behavior

Compiler reports an error: 'Type' cannot be constructed because it has no accessible initializers

Steps to reproduce

See the code below.

@Reducer(state: .equatable)
enum Feature1 {
 case a
 case b
}

@Reducer(state: .equatable)
enum Feature2 {
 case feature1(Feature1)
}

The Composable Architecture version information

1.10.2

Destination operating system

No response

Xcode version information

Version 15.3 (15E204a)

Swift Compiler version information

swift-driver version: 1.90.11.1 Apple Swift version 5.10 (swiftlang-5.10.0.13 clang-1500.3.9.4)
Target: arm64-apple-macosx14.0

[stephencelis]

@larryonoff This feature was added recently: https://github.com/pointfreeco/swift-composable-architecture/pull/2814

The macro has no knowledge of what the type of reducer being fed to a case is, so outside the default, you must specify the exact reducer kind and how to construct it using a default argument:

@Reducer(state: .equatable)
enum Feature2 {
  case feature1(Feature1.Body = Feature1.body)
}

Does this work for you?

[larryonoff]

@stephencelis thank you! it works like a charm!

Is it in the docs already?

[stephencelis]

@larryonoff I don't believe it's documented yet, but we'll PR some later today!