Subcomponent fields are not explicitly sorted, leading to Gradle build cache misses

Here’s a similar issue filed against InflationInject: https://github.com/cashapp/InflationInject/issues/181.

We’ve got the following @Subcomponent declared in our code:

@ActivityScope
@Subcomponent(modules = [MainActivityModule::class])
interface MainActivityComponent : PasscodeView.Injector {
  // other code

  @Subcomponent(modules = [ViewModule::class])
  interface ViewInjector {
    fun inflaterFactory(): InflationInjectFactory
  }
}

On CI, Dagger generates the following code for ViewInjector:

private static final class ViewInjectorImpl implements MainActivityComponent.ViewInjector {
  // other code

  @SuppressWarnings("unchecked")
  private void initialize() {
    this.refundPaymentPresenterProvider = ...
    this.factoryProvider = ...
    this.reportAbusePresenterProvider = ...
    this.factoryProvider2 = ...
    this.mainTabbedScreensPresenterProvider = ...
    this.inAppNotificationPresenterProvider = ...
    this.factoryProvider3 = ...
    this.activityContactPresenterProvider = ...
    this.factoryProvider4 = ...
    this.receiptDetailsPresenterProvider = ...
    this.factoryProvider5 = ...
    this.receiptPresenterProvider = ...
    this.factoryProvider6 = ...
  }
}

And on one of the dev machines the generated code looks like this:

private static final class ViewInjectorImpl implements MainActivityComponent.ViewInjector {
  // other code

  @SuppressWarnings("unchecked")
  private void initialize() {
    this.receiptPresenterProvider = ...
    this.factoryProvider = ...
    this.receiptDetailsPresenterProvider = ...
    this.factoryProvider2 = ...
    this.activityContactPresenterProvider = ...
    this.factoryProvider3 = ...
    this.refundPaymentPresenterProvider = ...
    this.factoryProvider4 = ...
    this.reportAbusePresenterProvider = ...
    this.factoryProvider5 = ...
    this.mainTabbedScreensPresenterProvider = ...
    this.inAppNotificationPresenterProvider = ...
    this.factoryProvider6 = ...
  }
}

The difference is that the fields aren’t declared in the same order, and even though this doesn’t have any effect on code correctness (please correct me if I’m wrong here), Gradle’s input comparison will fail leading to a cache miss.

The solution might be to sort entries before generating code, similar to https://github.com/cashapp/InflationInject/pull/182.

[Chang-Eric]

Cool, thanks for the update, and glad it worked out!

[Egorand]

I’ve got an update: looks like the original source of the issue was the InflationInject bug that I linked - after merging the fix I don’t see any Gradle cache issues in the code that Dagger generates. Given that our @Subcomponent depended on the InflationInjectFactory, it makes sense that the unstable order of entries in the file was propagated to the subcomponent. I’m gonna close this issue as I believe there’s nothing to be done here on the Dagger side, thanks for taking a look!