Generating objects for combination approval tests

[ragunathjawahar]

Folks, curious to find out if there's a way to do this with Approvals or a different 3rd party library. I checked the public APIs, I wasn't able to find anything. I found a function 9 variation but not the others.

I have an object with x number of parameters and there are y number of objects. How do I generate inputs for them to use with combination approvals. For instance,

My classes

data class Coffee(
  val estate: String,
  val roast: Roast,
  val grindSize: GrindSize
)

enum class Roast {
  Light, Medium, Dark
}

enum class GrindSize {
  Fine, MediumFine, Medium, Coarse
}

Expected

Coffee(estate = Attikan, roast = Light, grindSize = Fine)
Coffee(estate = Attikan, roast = Light, grindSize = MediumFine)
Coffee(estate = Attikan, roast = Light, grindSize = Medium)
Coffee(estate = Attikan, roast = Light, grindSize = Coarse)
Coffee(estate = Attikan, roast = Medium, grindSize = Fine)
Coffee(estate = Attikan, roast = Medium, grindSize = MediumFine)
Coffee(estate = Attikan, roast = Medium, grindSize = Medium)
Coffee(estate = Attikan, roast = Medium, grindSize = Coarse)
Coffee(estate = Attikan, roast = Dark, grindSize = Fine)
Coffee(estate = Attikan, roast = Dark, grindSize = MediumFine)
Coffee(estate = Attikan, roast = Dark, grindSize = Medium)
Coffee(estate = Attikan, roast = Dark, grindSize = Coarse)

[LarsEckart]

How about this:

import org.approvaltests.combinations.CombinationApprovals;
import org.junit.jupiter.api.Test;

public class CoffeeTests {

  @Test
  void testAllCombinations() {
    String[] estates = new String[]{"Attikan", "Other"};
    CombinationApprovals.verifyAllCombinations(this::applesauce, estates, Roast.values(),
        GrindSize.values());
  }

  private String applesauce(String estate, Roast roast, GrindSize grindSize) {
    Barista barista = new Barista();
    Coffee coffee = new Coffee(estate, roast, grindSize);
    return barista.make(coffee);
  }

  class Barista{

    public String make(Coffee coffee) {
      return "preparing ... " + coffee + " ... done";
    }
  }

  record Coffee(
      String estate,
      Roast roast,
      GrindSize grindSize) {
  }

  enum Roast {
    Light, Medium, Dark
  }

  enum GrindSize {
    Fine, MediumFine, Medium, Coarse
  }

}

[ragunathjawahar]

Right, this works for simple objects and I use this. What happens when one of the input values to verifyAllCombinations is a List<Coffee>, List<Location>, and List<Cafe>. And each of these objects have 3, 4, 5 properties each? That would total to 12 parameters and verifyAllCombinations takes in 9 parameters at most. If I am not wrong.

[LarsEckart]

ah, so you rather have a separate Combinator and the result of that as 2nd argument then?

List<Coffee> listOfAllCombinations = whatYouWant(String type, Roast roast, List<Ingridient> ingrediants ....);
CombinationApprovals.verifyAllCombinations(this::applesauce, listOfAllCombinations);

[ragunathjawahar]

I wrote a simple class that can do this at the moment,

val coffee = ObjectStream
  .of(Coffee::class)
  .property("estate", "Attikan")
  .property("roast", Roast.Light, Roast.Medium, Roast.Dark)
  .property("grindSize", GrindSize.Fine, GrindSize.MediumFine, GrindSize.Medium, GrindSize.Coarse)
  .generate()

coffee.onEach(::println)

Coffee(estate = Attikan, roast = Light, grindSize = Fine)
Coffee(estate = Attikan, roast = Light, grindSize = MediumFine)
Coffee(estate = Attikan, roast = Light, grindSize = Medium)
Coffee(estate = Attikan, roast = Light, grindSize = Coarse)
Coffee(estate = Attikan, roast = Medium, grindSize = Fine)
Coffee(estate = Attikan, roast = Medium, grindSize = MediumFine)
Coffee(estate = Attikan, roast = Medium, grindSize = Medium)
Coffee(estate = Attikan, roast = Medium, grindSize = Coarse)
Coffee(estate = Attikan, roast = Dark, grindSize = Fine)
Coffee(estate = Attikan, roast = Dark, grindSize = MediumFine)
Coffee(estate = Attikan, roast = Dark, grindSize = Medium)
Coffee(estate = Attikan, roast = Dark, grindSize = Coarse)

I want to make sure that I am not wasting my time reinventing the wheel here. Thoughts?

[ragunathjawahar]

This way I can configure each individual object and pass them down stream to verifyAllCombinations 🤔

[ragunathjawahar]

More concrete example, how do we bring functions like these under test, when we have more than 9 input parameters. Assignment and Briefing themselves are complex objects. Combination approvals could work here, but it would hit the limits when we have more complex objects.

[ragunathjawahar]

@LarsEckart and @isidore, curious to find out if I am missing something obvious here. If yes, can you folks point me in the right direction?