Update hilt-2.59.2 to hilt-2.60: compilation error of file that uses @AssistedFactory

[agrahn]

Since tonight's hilt update through Renovate, my project does not compile anymore. I am getting a cannot find symbol error in a generated file:

/home/runner/work/Android-Password-Store/Android-Password-Store/app/build/generated/hilt/component_sources/debug/app/passwordstore/DaggerApplication_HiltComponents_SingletonC.java:15: error: cannot find symbol

import app.passwordstore.data.passfile.PasswordEntry_Factory_Impl;
> Task :app:hiltJavaCompileDebug
                                      ^
  symbol:   class PasswordEntry_Factory_Impl
  location: package app.passwordstore.data.passfile
1 error

The original file, where @AssistedFactory annotation is used, is located here: https://github.com/agrahn/Android-Password-Store/blob/develop/format/common/src/main/kotlin/app/passwordstore/data/passfile/PasswordEntry.kt

Here is some probably relevant code from that file:

package app.passwordstore.data.passfile
...
import dagger.assisted.Assisted
import dagger.assisted.AssistedFactory
import dagger.assisted.AssistedInject
...
public class PasswordEntry @AssistedInject constructor(                                                                         
   private val clock: UserClock,                                                     
   private val totpFinder: TotpFinder,                 
   @Assisted chars: CharArray,                        
) { 
...
  @AssistedFactory
  public interface Factory {
    public fun create(chars: CharArray): PasswordEntry
  }
...
}

What can I do about this? Please help.

[garabais]

Thanks for the code sample @agrahn .

I was able to reproduce the bug, and I'm working on a fix. The issue is caused by a bug in the propagation of the fastInit flag to Hilt's internal compilation tasks.

In the meantime, you can work around this by adding the following to your app-level build file to manually force the flag:

For Kotlin DSL (build.gradle.kts):

tasks.withType<JavaCompile>().configureEach {
    options.compilerArgs.add("-Adagger.fastInit=enabled")
}

For Groovy (build.gradle):

tasks.withType(JavaCompile).configureEach {
    options.compilerArgs.add("-Adagger.fastInit=enabled")
}

Once the next Hilt version is released and you upgrade, you can safely remove this workaround.

Alternatively, if you would like to test the fix sooner, you can use our HEAD-snapshots as soon as the change is merged by following the instructions at https://dagger.dev/dev-guide/versions.

[agrahn]

Thank you so much for looking into this, and also for the suggested temporary fix.

[garabais]

Hi again,

Just a follow up, I've have been investigating further the issue. Specifically why not having fast init caused the compilation issue. After looking into the code the error is exposing an error in your setup. Usually whenever a dagger/hilt specific annotation (like @AssistedFactory) is being used we expect the library to apply the dagger/hilt compiler.

The fact that it used to compile was because of some of fastInit optimizations, which is why enabling it again fixes the build. However, it's not something you should rely on. If you modify your dagger/hilt usage in library it could surface again. We have filled a bug internally about this to keep the behaviour consistent across modes.

We are still fixing the fastInit propagation issue (and you probably want to keep the workaround it until the next release), but the real solution is to apply the compiler to your format/common library.

You can do this by adding KSP and the Hilt compiler to format/common/build.gradle.kts:

  plugins {
    id("com.github.android-password-store.kotlin-jvm-library")
+   alias(libs.plugins.ksp)
  }
 
  dependencies {
    ...
    implementation(libs.dagger.hilt.core)
+   ksp(libs.dagger.hilt.compiler)
    ...
  }