Service schema getters?

[rulrok]

I find my self in a situation where I had to prepare a method only to support me with unit tests.

I am using typescript and typing was not helping me to for example, access properties from metadata without code repetition.
Further more, I found that I could not store object instances in metadata because it would have problems during serialization among services. Thus, metadata would only work nicely with simple types (strings/number/etc).

One workaround I found was to use a HOF to build the mixin with closure over the complex types I needed to maintain.

E.g:

const mixinBuilder = (objDependency) => {

   const internalMap = new Map();

   return {
      name: 'name',
      created(){ ... },
      methods: {
        mapSize(){
          return internalMap.size;
        }
      }
  }

}

if somehow I could define getters it would be more syntactically meaningful?