kotlin中带命名参数的Dagger 2构造函数注入

I have this dependency:

@Singleton
class SpiceMix @Inject constructor(@field:[Named("oregano")] private val oregano: Spice,
                                   @field:[Named("sage")] private val sage: Spice,
                                   @field:[Named("rosemary")] private val rosemary: Spice) 

以及一个模块来实现其依赖性:

@Module
class SpiceModule {

    @Provides
    @Named("oregano")
    @Singleton
    fun provideOregano(): Spice = Oregano()

    @Provides
    @Named("sage")
    @Singleton
    fun provideSage(): Spice = Sage()

    @Provides
    @Named("rosemary")
    @Singleton
    fun provideRosemary(): Spice = Rosemary()

The SpiceMix is then injected in various locations of my app.

但是，这不会编译，我得到一个错误:

Spice cannot be provided without an @Provides-annotated method

I think the @Named annotations do not quite work in my constructor signature. I am not quite sure how I can make it work.

Note: this compiles fine if I ditch the Named annotations and change the types of the constructor parameters to their concrete forms. However, Spice is an interface, and I need it for mocking purposes in my tests.

我能做什么？