Reasons for 'DependencyClient' macro not working

[iharandreyev]

Hello everyone.

I'm stuck in a situation where DependencyClient macro does not work.
It does not generate any code, and Expand Macro menu item does nothing.

When I create a new file, and paste the following code into it:

import ComposableArchitecture

@DependencyClient
struct SomeDependency {
  let doSomething: () -> Int
}

@ObservableState
struct SomeState {
  let value: Int
}

ObservableState macro does work, and it expands as expected.
But DependencyClient does not.
As soon a I click Expand Macro, I hear a click sound, observe no UI changes in Xcode, and when I try again, it's just stuck on Hide Macro Expansion

expand-macro-xcode-issue.mp4

I have a feeling that I've messed up my Xcode installation.

Any ideas?

[mbrandonw]

Hi @iharandreyev, just because the macro isn't expanding it doesn't mean the macro isn't working. Xcode may be having problems displaying the expansion, but I'm certain that the macro is still working.

Do you have evidence that shows that the macro is definitely not working? Like a compilation error somewhere? Any code you can share?

[iharandreyev]

@mbrandonw no parameter init for RemoteValueRepo in the video above is not synthesized by the macro.
let a = Self() does not compile
That's the reason I went asking for help

[mbrandonw]

And you have enabled the macro in Xcode? Are you able to provide a minimal project that demonstrates the problem you are seeing?

[iharandreyev]

Yes, I did enable the macro.
Otherwise the project would not compile at all. Now it compiles if I remove no parameter init attempt.

Here's a sample project.
RemoteValueApp.zip
One would be interested in FailingMacro.swift

[mbrandonw]

Thanks for that. The issue is the let. If you change it to a var it should work.

Currently lets are omitted from the initializer because they are given a default value (one that throws the Unimplemented error), and so Swift would not be able to set that variable again. We do have some changes planned for the macro that would make this possible, but it's just not how it is today.