Stuck on an issue?

Lightrun Answers was designed to reduce the constant googling that comes with debugging 3rd party libraries. It collects links to all the places you might be looking at while hunting down a tough bug.

And, if you’re still stuck at the end, we’re happy to hop on a call to see how we can help out.

Failing Mocks of SAM-Converted Objects - JDK 16 + Kotlin 1.5.31

See original GitHub issue

Prerequisites

Please answer the following questions for yourself before submitting an issue.

I am running the latest version
I checked the documentation and found no answer
I checked to make sure that this issue has not already been filed

Expected Behavior

I Expect MockK to still be able to MockK functional Interfaces in Kotlin 1.5.31 and JVM 16.

Current Behavior

Trying to Mock a Function Interface will cause mockK to throw exceptions

Failure Information (for bugs)

When we bumped Kotlin to 1.5.31 and JVM 15 to JVM 16, our Tests do not longer run because MockK fails to mock our functional Interfaces in the new Versions.

Steps to Reproduce

I created you a sample project which you can check out and run - it contains a working example of the Bug.

https://github.com/Staffbase/mockK-bug

Context

Please provide any relevant information about your setup. This is important in case the issue is not reproducible except for under certain conditions.

MockK version: 1.12.0
OS: Dockers ubuntu-latest, Arch Linux x86_64 (Kernel: 5.14.8-arch1-1), macOS
Kotlin version: 1.5.31
JDK version: openjdk 16.0.2 2021-07-20
JUnit version: 5.8.1
Type of test: Unit-Test

Failure Logs

Please include any relevant log snippets or files here.

Stack trace

io.mockk.MockKException: Failed matching mocking signature for
SignedCall(retValue=, isRetValueMock=true, retType=class kotlin.Unit, self=HookConsumer(#1), method=consumeHook(EntityHook), args=[com.staffbase.bugs.HookConsumerTest$sam$com_staffbase_entities_EntityHook$0@7007be6e], invocationStr=HookConsumer(#1).consumeHook(lambda {}))
left matchers: [any()]
	at io.mockk.impl.recording.SignatureMatcherDetector.detect(SignatureMatcherDetector.kt:99)
	at io.mockk.impl.recording.states.RecordingState.signMatchers(RecordingState.kt:39)
	at io.mockk.impl.recording.states.RecordingState.round(RecordingState.kt:31)
	at io.mockk.impl.recording.CommonCallRecorder.round(CommonCallRecorder.kt:50)
	at io.mockk.impl.eval.RecordedBlockEvaluator.record(RecordedBlockEvaluator.kt:63)
	at io.mockk.impl.eval.EveryBlockEvaluator.every(EveryBlockEvaluator.kt:30)
	at io.mockk.MockKDsl.internalEvery(API.kt:92)
	at io.mockk.MockKKt.every(MockK.kt:98)
	at io.mockk.MockKKt.justRun(MockK.kt:106)
	at com.staffbase.bugs.HookConsumerTest.mocking a SAM converted object will fail(HookConsumerTest.kt:30)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:567)
	at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:725)
	at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
	at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:131)
	at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:149)
	at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:140)
	at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:84)
	at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
	at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
	at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
	at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:64)
	at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:45)
	at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:37)
	at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
	at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$7(TestMethodTestDescriptor.java:214)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:210)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:135)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:66)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:151)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
	at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:155)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
	at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:155)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
	at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
	at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:35)
	at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
	at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:54)
	at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:108)
	at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:88)
	at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:54)
	at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:67)
	at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:52)
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:96)
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:75)
	at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.processAllTestClasses(JUnitPlatformTestClassProcessor.java:99)
	at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.access$000(JUnitPlatformTestClassProcessor.java:79)
	at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor.stop(JUnitPlatformTestClassProcessor.java:75)
	at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.stop(SuiteTestClassProcessor.java:61)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:567)
	at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
	at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
	at org.gradle.internal.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:33)
	at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:94)
	at jdk.proxy1/jdk.proxy1.$Proxy2.stop(Unknown Source)
	at org.gradle.api.internal.tasks.testing.worker.TestWorker.stop(TestWorker.java:135)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:567)
	at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
	at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
	at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:182)
	at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:164)
	at org.gradle.internal.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:414)
	at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
	at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:48)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630)
	at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:56)
	at java.base/java.lang.Thread.run(Thread.java:831)

Minimal reproducible code (the gist of this issue)

Please check out the already mentioned Repo I prepared, at: https://github.com/Staffbase/mockK-bug

// -----------------------[ GRADLE DEFINITIONS ] -----------------------
plugins {
    java
    kotlin("jvm") version "1.5.31"
}

group = "com.staffbase"
version = "1.0-SNAPSHOT"

repositories {
    mavenCentral()
}

java {
    toolchain {
        languageVersion.set(JavaLanguageVersion.of(16))
    }
}

tasks.withType<Test> {
    useJUnitPlatform()
}

dependencies {
    implementation(kotlin("stdlib"))

    testImplementation("io.mockk:mockk:1.12.0")
    testImplementation("org.junit.jupiter:junit-jupiter-api:5.8.1")
    testImplementation("org.junit.jupiter:junit-jupiter-engine:5.8.1")
    testImplementation("org.junit.jupiter:junit-jupiter-params:5.8.1")
}


// -----------------------[ YOUR CODE STARTS HERE ] -----------------------
package com.staffbase.bugs

import io.mockk.justRun
import io.mockk.mockk
import org.junit.jupiter.api.Assertions.assertFalse
import org.junit.jupiter.api.Assertions.assertTrue
import org.junit.jupiter.api.Test

class HookConsumerTest {

    interface Entity

    @FunctionalInterface
    fun interface EntityHook<T : Entity>: (T) -> Unit

    class HookConsumer {
        fun consumeHook(hook: EntityHook<User>) {
            hook(User())
        }
    }

    class User : Entity

    @Test
    fun `the hook consumer works`() {
        var testBool = false
        val hook = EntityHook { _: User ->
            testBool = true
        }

        assertFalse(testBool)

        HookConsumer().consumeHook(hook)

        assertTrue(testBool)
    }

    @Test
    fun `mocking a SAM converted object will fail`() {
        val hookConsumer = mockk<HookConsumer>()
        justRun { hookConsumer.consumeHook(any()) }
    }
}
// -----------------------[ YOUR CODE ENDS HERE ] -----------------------

Issue Analytics

State:
Created 2 years ago
Reactions:1
Comments:6

Top GitHub Comments

1reaction

timkantecommented, May 11, 2022

Please reopen - the issue still persists. (JDK 18 and Kotlin 1.6.21)

0reactions

andrashatvanicommented, Oct 14, 2022

If you can go without the syntactic sugar and can access the function object then use Kotlin object lambda objects: Instead of

val hook = EntityHook<User> {  }

use

val hook = object: EntityHook<User> {
    override fun invoke(p1: User) {
        TODO("Not yet implemented")
    }
}

then you can use mockkObject

mockkObject(hook)
every { hook.invoke(any()) } answers {}

Top Results From Across the Web

How to mock objects in Kotlin? - Stack Overflow

I've tried different options like Mockk, How to mock a Kotlin singleton object? and using PowerMock in the same way as in java...

Troubleshoot Live Code

Lightrun enables developers to add logs, metrics and snapshots to live code - no restarts or redeploys required.

Start Free

Top Related Reddit Thread

No results found

Top Related Tweet

No results found

Top Related Dev.to Post

No results found

Failing Mocks of SAM-Converted Objects - JDK 16 + Kotlin 1.5.31

Prerequisites

Expected Behavior

Current Behavior

Failure Information (for bugs)

Steps to Reproduce

Context

Failure Logs

Stack trace

Minimal reproducible code (the gist of this issue)

Issue Analytics

Top GitHub Comments

Top Results From Across the Web

Top Related Medium Post

Top Related StackOverflow Question

Troubleshoot Live Code

Top Related Reddit Thread

Top Related Hackernoon Post

Top Related Tweet

Top Related Dev.to Post

Top Related Hashnode Post

"Duplicate class io.mockk.ValueClassSupportKt found" when using in 1.12.0

Message from Assertk assertions is not printed when using withArg block.