Monix BIO usage

Testing Monix BIO programs is very similar to testing regular Monix programs.

Tests must return monix.bio.Task[Expectation] instances.

Note that in Monix BIO Task[A] is an alias for the IO[Throwable, A] effect.

Installation

You'll need to install an additional dependency in order to use weaver to test Monix BIO rograms.

SBT

libraryDependencies +=  "com.disneystreaming" %% "weaver-monix-bio" % "0.6.11" % Test
testFrameworks += new TestFramework("weaver.framework.MonixBIO")

Mill

object test extends Tests {
  def ivyDeps = Agg(
    ivy"com.disneystreaming::weaver-monix-bio:0.6.11"
  )
  def testFrameworks = Seq("weaver.framework.MonixBIO")
}

Usage

For basic usage, simply extend SimpleIOSuite. Porting the example test, for instance:

import monix.bio.Task
import weaver.monixbiocompat._

object MySuite extends SimpleIOSuite {

  val randomUUID = Task(java.util.UUID.randomUUID())  // Use of `Task` instead of `IO`

  test("hello side-effects") {
    for {
      x <- randomUUID
      y <- randomUUID
    } yield expect(x != y)
  }

}

Usage with shared resources

Monix BIO program tests make use of shared resorces in the same way as Cats Effect program tests.

Extend IOSuite, implementing the sharedResource member. For example:

import monix.bio.Task
import weaver.monixbiocompat._
import cats.effect._

// Using http4s
import org.http4s.client.blaze._
import org.http4s.client._

object HttpSuite extends IOSuite {

  // Sharing a single http client across all tests
  override type Res = Client[Task]
  override def sharedResource : Resource[Task, Res] =
    BlazeClientBuilder[Task](scheduler).resource

  // The test receives the shared client as an argument
  test("Good requests lead to good results") { httpClient =>
    for {
      statusCode <- httpClient.get("https://httpbin.org/get"){
        response => Task.pure(response.status.code)
      }
    } yield expect(statusCode == 200)
  }

  test("Bad requests lead to bad results") { httpClient =>
    for {
      statusCode <- httpClient.get("https://httpbin.org/oops"){
        response => Task.pure(response.status.code)
      }
    } yield expect(statusCode == 404)
  }


}