'explodeCodeSourceDebug' uses this output of task 'generateDebugProto' without declaring an explicit or implicit dependency after Gradle update to 8.0.2

[ivanalvarado]

We're experiencing the following error after updating gradle from 7.6.1 -> 8.0.2

A problem was found with the configuration of task ':my-library:generateDebugProto' (type 'GenerateProtoTask').
  - Gradle detected a problem with the following location: '/path/to/MyProject/my-library/build/generated/source/proto/debug'.
    
    Reason: Task ':my-library:explodeCodeSourceDebug' uses this output of task ':my-library:generateDebugProto' without declaring an explicit or implicit dependency. This can lead to incorrect results being produced, depending on what order the tasks are executed.
    
    Possible solutions:
      1. Declare task ':my-library:generateDebugProto' as an input of ':my-library:explodeCodeSourceDebug'.
      2. Declare an explicit dependency on ':my-library:generateDebugProto' from ':my-library:explodeCodeSourceDebug' using Task#dependsOn.
      3. Declare an explicit dependency on ':my-library:generateDebugProto' from ':my-library:explodeCodeSourceDebug' using Task#mustRunAfter.
    
    Please refer to https://docs.gradle.org/8.0.2/userguide/validation_problems.html#implicit_dependency for more details about this problem.

This appears like a misconfiguration at the plugin level, but not entirely sure.

We've added a workaround by adding the following to the affected module:

afterEvaluate {
    tasks.forEach {task ->
        if (task.name.contains("explodeCodeSourceDebug")) {
            task.dependsOn("generateDebugProto")
        }
        if (task.name.contains("explodeCodeSourceRelease")) {
            task.dependsOn("generateReleaseProto")
        }
    }
}

[JamesXNelson]

We're seeing a similar-ish issue on gradle 8.9:

FAILURE: Build failed with an exception.

* What went wrong:
A problem was found with the configuration of task ':proto:dh-protodoc:processResources' (type 'ProcessResources').
  - Gradle detected a problem with the following location: '/home/bender/dev/deephaven/iris/sanluis/proto/dh-protodoc/src/main/proto'.
    
    Reason: Task ':proto:dh-protodoc:processResources' uses this output of task ':proto:dh-protodoc:getProtos' without declaring an explicit or implicit dependency. This can lead to incorrect results being produced, depending on what order the tasks are executed.
    
    Possible solutions:
      1. Declare task ':proto:dh-protodoc:getProtos' as an input of ':proto:dh-protodoc:processResources'.
      2. Declare an explicit dependency on ':proto:dh-protodoc:getProtos' from ':proto:dh-protodoc:processResources' using Task#dependsOn.
      3. Declare an explicit dependency on ':proto:dh-protodoc:getProtos' from ':proto:dh-protodoc:processResources' using Task#mustRunAfter.

Worked around it via:

tasks.named('processResources') {
  dependsOn('getProtos')
}

For posterity, we have other proto builds that work fine. The one that is breaking is only doing protodocs:

We added a new task to sync all available .proto files into a single project to build a single page doc:

// Register a sync task to synchronize proto files
tasks.register('getProtos', Sync).configure {
  Sync getProtos ->
    getProtos.destinationDir = new File(projectDir, 'src/main/proto')
    getProtos.from(project(':proto').subprojects.findAll{ it.name.startsWith('proto-') }*.file('src/main/proto'))
}

Complete proto-related wiring here:

// Configure the Protobuf plugin
protobuf {
  protoc { artifact = "com.google.protobuf:protoc:${protocVersion}" }
  plugins {
    doc {
      artifact = "io.github.pseudomuto:protoc-gen-doc:1.5.1"
    }
  }

  // Configure tasks for generating Protobuf files
  generateProtoTasks {
    all().each {
      generateProtoTask ->
        generateProtoTask.dependsOn ':proto:dh-protodoc:getProtos'
        generateProtoTask.doFirst {
          project.configurations.names.findResults { it.startsWith('protobufToolsLocator') ? it : null }.each {
            String name ->
              project.configurations.findByName(name).files.each {
                File f ->
                  f.setExecutable(true, true)
              }
          }
        }
        generateProtoTask.doFirst {
          delete generateProtoTask.outputs
        }
        generateProtoTask.builtins {
          remove java
        }
        // Use proto-gen-doc to generate docs into a single html file at proto/dh-protodoc/build/docs/index.html
        generateProtoTask.plugins {
          doc {
            option 'html,index.html'
          }
        }
    }
  }
}

It looks like the generateProtoTask.dependsOn we added which was fine in gradle 7.X is no longer happy in 8.X.

Is there maybe something that changed such that src/main/proto has become a dependency of processResources, and our generateProtoTask.dependsOn 'getProtos' should have been processResources.dependsOn instead?