I believe

any<Type>()

works as well

I couldn't find anything about extension properties, neither in the documentation, nor issues on Github, nor stackoverflow, etc. I wonder if this is something so clear for everyone that doesn't need explanation and I'm just missing something

Hi all, how do I mockk a setter? Gettng complaints in test because the setter is called at init time of a mocked object.

every {mocked.myProperty } returns "some"

mockes the getter. How do I do the same for the setter?

Anyone try to mock databinding with mockk?

I believe you can transform a class in a KClass

I was trying to use

answers ManyAnswersAnswer

with a

listOf(ThrowingAnswer(myException), ConstantAnswer(myConstant))

but it doesn't seem to like having 2 types of answers in there

this feels a bit weird to me

"f:can sync" {
  val clock = mockk<Clock>()
  every { clock.instant() } returns YESTERDAY andThen NOW
}

"f:can delete" {
  val clock = mockk<Clock>()
  every { clock.instant() } returns YESTERDAY andThen NOW andThen NOW
}

the first one logs:

10:33:28.099 [kotest-engine-0 @coroutine#2] DEBUG io.mockk.impl.instantiation.AbstractMockFactory - Creating mockk for Clock name=#1
10:33:29.228 [kotest-engine-0 @coroutine#2] DEBUG io.mockk.impl.instantiation.AbstractMockFactory - Creating mockk for Instant name=child of #1#2

the second one

10:33:29.245 [kotest-engine-0 @coroutine#3] DEBUG io.mockk.impl.instantiation.AbstractMockFactory - Creating mockk for Clock name=#3
10:33:29.247 [kotest-engine-0 @coroutine#3] DEBUG io.mockk.impl.instantiation.AbstractMockFactory - Creating mockk for Instant name=child of #3#4

how comes in the first test it takes one second to create a mock?

is this answer still valid? https://stackoverflow.com/a/49819729

Not sure if this was posted here, but it seems that many people are having problems getting

MockK

to run when using

Kotest

4+ and running tests with the Kotest IntelliJ plugin: https://github.com/mockk/mockk/issues/459. I'm not sure if this happens for everyone, but if it does then it is blocking all

Kotest

users from really working with

MockK

in an easy way. It is not clear to me if this is a problem that needs to be fixed on the

Kotest

side or

MockK

side. Did anybody here experience the problem and have any more information or even workarounds? Please help us out in the issue or here on Slack 🙂.

At some point I started seeing debug logs printing from mockk, but can't remember when they started showing up. Is there a way to globally disable them?

Hi, I am pretty new to kotlin and just read a lot about mockk. I used it as well and it does work marvelously. But I am not 100% sure when I should use a slot capturing and when I use just the verify method without it. Can someone help me with giving useCases when I should use these 2 methods?

Testbleeding with @TestFactory: Hi, I am trying to minimize duplications in tests, so I want to Use JUnit5's TestFactory. It works fine for everything, unless it concerns mokk mocks. Example

import io.mockk.every
import io.mockk.mockk
import io.mockk.verify
import org.junit.jupiter.api.DynamicTest
import org.junit.jupiter.api.TestFactory

class Test {

  private val testService: TestService = mockk(relaxed = true)


  private val testStrings = listOf("1", "2")

  class TestService {
    fun test(string: String): String {
      return string
    }
  }

  @TestFactory
  fun tests() = testStrings
      .map { input: String ->
        DynamicTest.dynamicTest("should call service once for '$input'") {
          every {
            testService.test(any())
          } returns "foo"

          testService.test(input)

          verify(exactly = 1) { testService.test(any()) }
        }
      }
}

As you can see in the test, I am calling the mock just once. still, the testoutput is as shown on the screenshot. The second tests always fails. What am I doing wrong here? Can anybody help me? 🙂 I am using mokk 1.10.0, kotlin 1.3.72 and junit 5.6.2

I'm running into some trouble trying to verify that a field was not set, am I using the wrong syntax?

class Foo {
    var field: Int = 0
}

fun main() {
    val foo = spyk<Foo>()

    foo.field = 42

    // This works fine
    verify { foo setProperty "field" value 42 }
    // This should fail, but it throws "io.mockk.MockKException: can't find stub io.mockk.MockKMatcherScope$DynamicSetProperty@64a896b0"
    verify { foo setProperty "field" wasNot Called }
}

Hello I have a problem trying to mock a private method in a sealed class,

io.mockk.MockKException: can't find function someMethod() for dynamic call

sealed class SomeSealed {
    private fun someMethod() = ...

    data class SomeData() : SomeSealed()
}

What is the best way to test abstract class? let’s say I have a class A

abstract class A(param1: Param1, param2: Param2) {
  fun foo() {
    val param1result = param1.get()
    val param2result = param2.get()
    val result = calculateResult(param1result, param2)
  }
  
  abstract fun calculateResult(param1: Param1, param2: Param2): Smth
}

Now, I want to test it. But I can not create an instance of A, since its a abstract class. The only way I managed to make it work is to create a real A class and use spyk function:

class AReal: A {
  override fun calculateResult(...) {
    ...
  }
}

class Test {
  val aReal = spyk(AReal(...., .....))
}

Is there any other better way?

Hello, I have a class like

class MyClass(val dir: File) {

  fun stuff(filesNames: List<String>) {
    ...
    val file = File(dir, fileName)
    if (file.exists())
    ...
  }
}

What would be the right way in order to pass the check

if (file.exists())

?

Hey there! Is there alternative to Mockito’s

clearInvocations

in mockk? (clear invocation log without resetting the stubbing)

Is there somebody who can tell me how to mock/test a coroutine that takes a while to complete, like a network call? I have something like this in a test:

coEvery { mockRepo.saveToServer(mockArgument) } returns myResult

Now this will of course happen immediately. In reality it could take a moment. Now while this call is in flight, I flip a boolean to prevent issuing a second call while the first one is still underway. When it returns, I flip the boolean back. Is there a proper way to unit test this, preferably using

Mockk

, of course...?

Hello, i'm trying to mock Instant but I can't seem to get it to work. My approach:

object MockkInstant {
    var value: Instant = Instant.now()

    fun mock() {
        mockkStatic(Instant::class)

        every {
            Instant.now()
        } answers {
            value.minusMillis(0) // line 22 from stack trace below
        }
    }

    fun clear() {
        clearStaticMockk(Instant::class)
    }

    fun step(duration: Duration = 1.seconds) {
        value = value.add(duration) // extension function defined elsewhere
    }
}

Now in my tests i'm trying to do this:

"fixes calls to Instant.now()" {
    val a = Instant.now()
    delay(1)
    val b = Instant.now()
    a.shouldBe(b)
}

But I'm getting an error from the

answers

block:

Empty list doesn't contain element at index 0.
java.lang.IndexOutOfBoundsException: Empty list doesn't contain element at index 0.
	at kotlin.collections.EmptyList.get(Collections.kt:35)
	at kotlin.collections.EmptyList.get(Collections.kt:23)
	at io.mockk.MockKAnswerScope.getValueAny(API.kt:3834)
	at io.mockk.MockKAnswerScope.getValue(API.kt:2188)
	at io.glimpseprotocol.testing.mockk.MockkInstant$mock$2.invoke(MockkInstant.kt:22)
	at io.glimpseprotocol.testing.mockk.MockkInstant$mock$2.invoke(MockkInstant.kt:13)
	at io.mockk.MockKStubScope$answers$1.invoke(API.kt:2092)
	at io.mockk.MockKStubScope$answers$1.invoke(API.kt:2069)
	at io.mockk.FunctionAnswer.answer(Answers.kt:19)
...

I've seen other people using returns, but afaik that returns the same Instant object whereas I want to create a new one each time Instant.now() is called. Any suggestions?

Hi, i am trying to throw an error using mockk with flow method but is not working.

every { manager.startFunction() } throws(error)

I don´t find any solution, can someone help me please? Thanks.

I am trying to do something like

MockkKt.mockk()

but the

mockk()

function does not exist 🤔

I might already have asked this, but forgot the answer (or never asked)

@Test // <- junit5 annotation
fun publisher() {
    val publisher = mockk<Publisher>(relaxed = true)
    UseCase(publisher).doSomething()
    verify { publisher.publish(any<UseCase.Something>()) }
    verify { publisher.publish(any<String>()) }
}
interface Publisher {
    fun publish(any: Any)
    fun publish(event: Event) {
        publish(event as Any)
    }
    class Event(source: Any)
}
class UseCase(val publisher: Publisher) {
    fun doSomething() {
        publisher.publish(Something(""))
    }
    data class Something(val something: String)
}

the test passes. what am I not seeing?

Yes, in reality I am not devoting my time to mockk. I am persuiting my career. I know that some issues are resolved as PR by volounteers. Happy if community going to grow around mockk, but dont know the way how to achieve this. Again for me it is just time in life to grow professionaly that I cannot miss, so working days/nights and weekends. If some sufficient enough sponsorship also going to happen(through opencollective or other way) I would just hire some devs, but this is not the case now.

Hi, can someone pls explain me the difference between

mockk()

and

any()

. Why when i have smth like

coEvery { foo(any()) } returns SomeObject

it works. But when i replace

any()

with

mockk()

, its print out:

exception=io.mockk.MockKException: no answer found for: SomeClass(#9).foo$domain(ParamType(#5), continuation {})))

Hi. Is there a way to verify a service inside

class RequestSupplier : Supplier<Unit>

(nested class)?

I've finished writing pages on how to learn MockK coming from Mockito: https://notwoods.github.io/mockk-guidebook/docs/mockito-migrate/ Eventually I'm hoping to have something written for all of MockK's features, but I'm happy to have this section done!

hi guys, I have a function that looks like below

interface StorageService {
    fun upload(inputStream: InputStream): String
}

class LocalStorageService: StorageService {

    override upload(inputStream: InputStream): String {
        //Some uploading logic
    }
}

I want to verify that the function was called with the following code

verify {
    storageService.putFile(
        inputStream = withArg { assertEquals("Hello, World!".toByteArray(),it.readBytes())}
    )
}

and I got an error, that my inputStreams byteArray is empty, can anyone help me please

it seems mockk 1.10.3 does not support jdk 1.8. is that by design?

io/mockk/proxy/jvm/dispatcher/JvmMockKDispatcher has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0

Hello folks, I have recently translated the internal of MockK from Japanese (https://zenn.dev/oboenikui/articles/af44c158f9fa35) to English (https://chao2zhang.medium.com/unraveling-mockks-black-magic-e725c61ed9dd). Please take a look and let me know in case of mistakes and errors.