[KSP][Android] Delete a hilt view model breaks incremental compilation in ksp

[ZhaohuaZeng-at]

Hi team,

Congrats on the KSP release!
After migrating to KSP, I found that there is an issue related to @HiltViewModel in my Android project. If I delete the view model, the incremental compilation will break in KSP, with the following message:

/Users/zhaohua.zeng/AndroidStudioProjects/testhiltviewmodel/app/build/generated/ksp/debug/java/com/example/testhiltviewmodel/ProfileScreenViewModel_HiltModules_KeyModule_ProvideFactory.java:34: error: package ProfileScreenViewModel_HiltModules does not exist
    return Preconditions.checkNotNullFromProvides(ProfileScreenViewModel_HiltModules.KeyModule.provide());

I also created a simple repository to demonstrate this issue: https://github.com/ZhaohuaZeng-at/dagger-demo-viewmodel-bug-ksp
Overview of the repo branches:

• main: use KSP for dagger and hilt. Has one hilt view model ProfileScreenViewModel
• remove_viewmodel: In this branch, I remove the ProfileScreenViewModel
• kapt: Use Kapt instead for dagger and hilt.
• kapt-remove-viewmodel: Same as the remove_viewmodel branch but use kapt

Here is the steps to reproduce:

1. build project in main branch via "run app"
2. git checkout remove_viewmodel, build project incrementally via "run app"
3. see the compilation fails.

If I do a clean build in remove_viewmodel, build can succeed, but this is annoying.
This error is not reproducible with the kapt and kapt-remove-viewmodel branches.

[ansman]

I saw this too when I deleted an @AutoBind annotated object (this annotation is provided by auto-dagger)

[bcorso]

This looks like an issue in KSP. I've filed a bug here: google/ksp#1554.