etl4s

Testing

Use etl4s with the testing framework of your choice

Run nodes like normal functions 

import etl4s._

val times5: Transform[Int, Int] = Transform(_ * 5)

times5(5)

You will get: 

25

Run pipelines with unsafeRun:

import etl4s._

val plus2:  Transform[Int, Int] = Transform(_ + 2)
val times5: Transform[Int, Int] = Transform(_ * 5)

val p: Node[Int, Int] = plus2 ~> times5

p.unsafeRun(2)
Gives 
20
If you want to capture failures, wrap the run in your own Try: 
import scala.util.Try

Try(p.unsafeRun(2))
You will get: 
Success(20)

Or run through an effect with .compile[F] - .compile[Try] folds the outcome into a Try for you, which is convenient in assertions:

import etl4s._
import scala.util.Success

val plus2:  Transform[Int, Int] = Transform(_ + 2)
val times5: Transform[Int, Int] = Transform(_ * 5)
val p: Node[Int, Int] = plus2 ~> times5

p.compile[Try].unsafeRun(2)
You will get: 
Success(20)

See Effect polymorphism for the other effects.

Testing config pipelines

For nodes that .requires config, supply it with .provide(cfg) (or its alias .provideContext) before running - swap in test config at the edge:

import etl4s._

case class Cfg(multiplier: Int)

val scaled = Transform[Int, Int].requires[Cfg] { cfg => n => n * cfg.multiplier }

scaled.provide(Cfg(10)).unsafeRun(5)
You will get: 
50