Cats Integration

Scala3Mock comes with a Cats integration that provides a withExpectations function that work with a MonadError[?, Throwable] instead of the simple value that the default library provide. This is pretty useful if your tests are defined in term of monads (Cats-Effect's IO, Scala's Future via alleycats, etc…).

You'll need to add a new dependency to your build.sbt:

libraryDependencies += "eu.monniot" %% "scala3mock-cats" % "0.6.6" % Test

Once added, simply replace the ScalaMocks import with the Cats one:

- import eu.monniot.scala3mock.ScalaMocks.*
+ import eu.monniot.scala3mock.cats.ScalaMocks.*

You can then use the library like usual, with the value passed to withExpectations being a monad instead of any values.

import eu.monniot.scala3mock.cats.ScalaMocks.*
import cats.effect.SyncIO

val fa = withExpectations() {
    val fn = mockFunction[Int, String]
    fn.expects(*).returns("Hello reader")

    SyncIO(fn(2))
}
// fa: SyncIO[String] = FlatMap(
//   ioe = Suspend(
//     hint = Delay,
//     thunk = repl.MdocSession$MdocApp$$Lambda$11913/0x0000000103003440@40e2b75e
//   ),
//   f = eu.monniot.scala3mock.cats.ScalaMocks$package$$$Lambda$11914/0x0000000103007040@2ed1fe14
// )

fa.unsafeRunSync()
// res0: String = "Hello reader"