core

Provides utilities for declaring command line processors and plugin registrars.

BaseCommandLineProcessor and CompilerOptionsHost

CompilerOptionsHost is a base class for an object that declares the compiler plugin's CLI and compiler configuration options.

For example:

object MyPluginOptions : CompilerOptionsHost {
    val isExperimentalTransformEnabled by flag("experimental-transform", "Enable experimental transform")
    val packageToTransform by singularString("package", "<package FQN>", "Package to transform")
}

class MyCliProcessor : BaseCommandLineProcessor(MyPluginOptions) {
    override val pluginId: String = "my-plugin"
    override val options: CompilerOptionsHost = MyPluginOptions
}

This takes care of parsing the command line arguments and adding them to the compiler configuration. The properties can be used to access the configuration, e.g. compilerConfiguration[MyPluginOptions.packageToTransform].

BaseSpecCompilerPluginRegistrar

BaseSpecCompilerPluginRegistrar is a base class for a compiler plugin registrar that uses a two-step process to create a spec object from compiler configuration, and then create extensions from that spec object. This is useful for clarity, but also because the spec can easily be set in tests - that way you don't need to muck around with individual compiler argument strings.