Lightsaber

Lightsaber is a Dagger 2 plugin that detects unused code in your Modules, Components and Subcomponents

Works with

Dagger 2 (kapt, ksp and javac annotation processor)
Anvil (kapt)

What to expect

/path/module/com/example/MyComponent.java:6:8: e: The @BindsInstance `myInt` declared in `test.MyComponent` is not used. [UnusedBindsInstances]

This plugin contains several rules:

Empty @Component and @Subcomponent
Unused @BindsInstance
Unused @Provides or @Binds inside @Modules
Unused @Component(dependencies)
Unused @Inject
Unused member injection methods (Component.inject(Foo))
Unused @Modules
Unused Scopes (for example: @Singleton)

How to use it

Add the plugin to your project:

// build.gradle.kts
plugins {
    id("io.github.schwarzit.lightsaber") version "0.0.18"
}

And run ./gradlew lightsaberCheck. Lightsaber will check your code and fail if there is any issue.

Configuration

You can change that default for each rule from error to warnings or even ignore it completely like this:

import schwarz.it.lightsaber.gradle.Severity

lightsaber {
  emptyComponents = Severity.Error
  unusedBindsInstances = Severity.Error
  unusedBindsAndProvides = Severity.Error
  unusedDependencies = Severity.Error
  unusedInjects = Severity.Error
  unusedMembersInjection = Severity.Error
  unusedModules = Severity.Error
  unusedScopes = Severity.Error
}

Suppress

Lightsaber supports the @Suppress annotation. If you want to suppress an issue, you only have to add the @Suppress annotation above the reported element with the rule name. Example:

@Module
class MyModule {
    @Suppress("UnusedBindsAndProvides")
    @Provides
    fun providesPotatoes() = "potatoes"
}

How to build it

Clone the repo and execute:

./gradlew build