lift value out of / or into ZIO to assert it - zio

Question

I have a ZIO that looks like this:
ZIO[transactor.Transactor[Task], Serializable, String]
and I need to assert the String, that is in that ZIO with another plain String.
So my question is:
How can I assert the plain String, with the String in the ZIO, or
can I lift the String into that same ZIO, to assert it with this one:
ZIO[transactor.Transactor[Task], Serializable, String]
I´m working with ZIO-Test as my testing framework.

Answer 1

I got this based on the rock the jvm zio course. Important things are highlighted in the comments
package com.w33b
import zio.test._
import zio._
object ZIOAssert extends ZIOSpecDefault {
class ATask
abstract class Transact[ATask] {
def get(): String
def put(ATask: ATask): ATask
}
// This is the mock service that we will use to create a ZLayer
val mockTransact = ZIO.succeed(new Transact[ATask] {
override def get(): String = "hello"
override def put(aTask: ATask): ATask = new ATask
})
// This is the method we are testing and we need a service (Zlayer) associated with it.
// We then use the service to invoke a method to get our return value
def methodUnderTest: ZIO[Transact[ATask], Serializable, String] = {
for {
trans <- ZIO.service[Transact[ATask]]
tVal = trans.get()
} yield tVal
}
def spec = suite("Let's test that ZIO lift")(
test("lets test that lift") {
assertZIO(methodUnderTest)(Assertion.equalTo("hello"))
}
).provide(ZLayer.fromZIO(mockTransact)) // Important to provide the layer or we can't test
}

Answer 2

with ZIO 2.x
val spec = suite("tetst")(
test("whatever"){
val effect: ZIO[transactor.Transactor[Task], Serializable, String] = ???
val expected: String = ???
for {
value <- effect
} yield assertTrue(value == expected)
}
)
In general, you just create here a ZIO with the assertion in the success channel.