KSP up-to-date after changing processor code

[ansman]

I'm working on a small example project where I have 3 Gradle modules:

• api - Contains my annotations
• compiler - Contains my Symbol Processor (and an annotation processor)
• test - Contains some test code

When I make an ABI compatible change in my compiler, kspKotlin is still considered up-to-date and the updated code won't be reflected. KAPT correctly runs again:

$ ./gradlew :test:assemble --console plain
Configuration cache is an incubating feature.
Reusing configuration cache.
> Task :compiler:processResources NO-SOURCE
> Task :api:processResources NO-SOURCE
> Task :api:compileKotlin UP-TO-DATE
> Task :api:compileJava NO-SOURCE
> Task :api:classes UP-TO-DATE
> Task :api:jar UP-TO-DATE
> Task :api:inspectClassesForKotlinIC UP-TO-DATE
> Task :compiler:kaptGenerateStubsKotlin
> Task :compiler:kaptKotlin UP-TO-DATE
> Task :compiler:compileKotlin
> Task :compiler:compileJava NO-SOURCE
> Task :compiler:classes UP-TO-DATE
> Task :compiler:jar
> Task :compiler:inspectClassesForKotlinIC
> Task :test:kspKotlin UP-TO-DATE
> Task :test:processResources NO-SOURCE
> Task :test:kaptGenerateStubsKotlin UP-TO-DATE
> Task :test:kaptKotlin
> Task :test:compileKotlin
> Task :test:compileJava NO-SOURCE
> Task :test:classes UP-TO-DATE
> Task :test:jar
> Task :test:assemble
> Task :test:inspectClassesForKotlinIC

BUILD SUCCESSFUL in 816ms
14 actionable tasks: 8 executed, 6 up-to-date
Configuration cache entry reused.

Notice that kspKotlin is considered UP-TO-DATE here while kaptKotlin runs again.

Here you can see the --info output between KSP and KAPT:

> Task :test:kaptKotlin
Transforming api.jar with StructureTransformAction
Transforming kotlin-stdlib-jdk8-1.8.10.jar with StructureTransformAction
Transforming kotlin-stdlib-jdk7-1.8.10.jar with StructureTransformAction
Transforming kotlin-stdlib-1.8.10.jar with StructureTransformAction
Transforming kotlin-stdlib-common-1.8.10.jar with StructureTransformAction
Transforming annotations-13.0.jar with StructureTransformAction
file or directory '/Users/nicklas/Repositories/example-processor/test/src/main/java', not found
file or directory '/Users/nicklas/Repositories/example-processor/test/src/generatedByKspKotlin/kotlin', not found
file or directory '/Users/nicklas/Repositories/example-processor/test/build/generated/ksp/main/java', not found
Caching disabled for task ':test:kaptKotlin' because:
  Build cache is disabled
Task ':test:kaptKotlin' is not up-to-date because:
  Input property 'kaptClasspath' file /Users/nicklas/Repositories/example-processor/compiler/build/libs/compiler.jar has changed.
The input changes require a full rebuild for incremental task ':test:kaptKotlin'.
Running kapt annotation processing using the Gradle Worker API
Using workers NONE isolation mode to run kapt

> Task :test:kspKotlin UP-TO-DATE
file or directory '/Users/nicklas/Repositories/example-processor/test/src/main/java', not found
file or directory '/Users/nicklas/Repositories/example-processor/test/src/main/java', not found
Caching disabled for task ':test:kspKotlin' because:
  Build cache is disabled
Skipping task ':test:kspKotlin' as it is up-to-date.
Resolve mutations for :test:kaptGenerateStubsKotlin (Thread[Execution worker,5,main]) started.
:test:kaptGenerateStubsKotlin (Thread[Execution worker,5,main]) started.

The change I'm making is changing a string inside the compiler module.
This is using Gradle 7.6, Kotlin 1.8.10, KSP 1.8.10-1.0.9 on Java 18.

I'll try to add a small repro later.

[ansman]

I've attached a test project: ksp-incremental-issue.zip

It contains the following modules:

• compiler - A module with a dummy annotation processor and a dummy symbol processor.
• app - A module with an annotated file.
• test - A module with a test case that shows the issue.

Just run ./gradlew :test:check to run the test.

The test does the following:

1. Copies the compiler and app modules to a temporary directory
2. Runs :app:assemble
3. Checks that the tasks ran. It checks both the kaptKotlin and kspKotlin tasks for parity
4. Runs :app:assemble again
5. Checks that the tasks are up to date
6. Change the compiler to generate slightly different code
7. Runs :app:assemble again
8. Checks that the tasks ran

Step 9 fails as the kspKotlin task is up-to-date

[ting-yuan]

Thanks for reporting and the test case! I've verified the commit with it.