How to use TestDispatcherInterceptor class of io.kotest.engine.test.interceptors package

Best Kotest code snippet using io.kotest.engine.test.interceptors.TestDispatcherInterceptor

TestCaseExecutor.kt

Source:TestCaseExecutor.kt

...19import io.kotest.engine.test.interceptors.SoftAssertInterceptor20import io.kotest.engine.test.interceptors.SupervisorScopeInterceptor21import io.kotest.engine.test.interceptors.TestCaseExtensionInterceptor22import io.kotest.engine.test.interceptors.TestCoroutineInterceptor23import io.kotest.engine.test.interceptors.TestDispatcherInterceptor24import io.kotest.engine.test.interceptors.TestFinishedInterceptor25import io.kotest.engine.test.interceptors.TestPathContextInterceptor26import io.kotest.engine.test.interceptors.TimeoutInterceptor27import io.kotest.engine.test.interceptors.blockedThreadTimeoutInterceptor28import io.kotest.engine.test.interceptors.coroutineDispatcherFactoryInterceptor29import io.kotest.engine.test.interceptors.coroutineErrorCollectorInterceptor30import io.kotest.mpp.Logger31import kotlin.time.Duration32import kotlin.time.TimeSource33/**34 * Executes a single [TestCase].35 *36 * Uses a [TestCaseExecutionListener] to notify callers of events in the test lifecycle.37 *38 */39@OptIn(ExperimentalKotest::class)40class TestCaseExecutor(41   private val listener: TestCaseExecutionListener,42   private val defaultCoroutineDispatcherFactory: CoroutineDispatcherFactory = NoopCoroutineDispatcherFactory,43   private val configuration: ProjectConfiguration,44) {45   private val logger = Logger(TestCaseExecutor::class)46   suspend fun execute(testCase: TestCase, testScope: TestScope): TestResult {47      val timeMark = TimeSource.Monotonic.markNow()48      val interceptors = listOfNotNull(49         TestPathContextInterceptor,50         TestFinishedInterceptor(listener),51         InvocationCountCheckInterceptor,52         SupervisorScopeInterceptor,53         if (platform == Platform.JVM) coroutineDispatcherFactoryInterceptor(defaultCoroutineDispatcherFactory) else null,54         if (platform == Platform.JVM) coroutineErrorCollectorInterceptor() else null,55         TestCaseExtensionInterceptor(configuration.registry),56         EnabledCheckInterceptor(configuration),57         LifecycleInterceptor(listener, timeMark, configuration.registry),58         AssertionModeInterceptor,59         SoftAssertInterceptor(),60         CoroutineLoggingInterceptor(configuration),61         if (platform == Platform.JVM) blockedThreadTimeoutInterceptor(configuration, timeMark) else null,62         TimeoutInterceptor(timeMark),63         TestInvocationInterceptor(configuration.registry, timeMark),64         InvocationTimeoutInterceptor,65         if (platform == Platform.JVM && testCase.config.testCoroutineDispatcher) TestDispatcherInterceptor() else null,66         if (platform == Platform.JVM && testCase.config.coroutineTestScope) TestCoroutineInterceptor() else null,67         CoroutineDebugProbeInterceptor,68      )69      val innerExecute: suspend (TestCase, TestScope) -> TestResult = { tc, scope ->70         logger.log { Pair(testCase.name.testName, "Executing test") }71         tc.test(scope)72         try {73            TestResult.Success(timeMark.elapsedNow())74         } catch (e: Throwable) {75            TestResult.Success(Duration.ZERO) // workaround for kotlin 1.576         }77      }78      return interceptors.foldRight(innerExecute) { ext, fn ->79         { tc, sc -> ext.intercept(tc, sc, fn) }...

TestDispatcherInterceptor.kt

Source:TestDispatcherInterceptor.kt

...18 * If the current dispatcher is already a [TestDispatcher] then this interceptor is a no-op.19 */20@ExperimentalCoroutinesApi21@ExperimentalStdlibApi22actual class TestDispatcherInterceptor : TestExecutionInterceptor {23   private val logger = Logger(TestDispatcherInterceptor::class)24   override suspend fun intercept(25      testCase: TestCase,26      scope: TestScope,27      test: suspend (TestCase, TestScope) -> TestResult28   ): TestResult {29      return when (coroutineContext[CoroutineDispatcher]) {30         is TestDispatcher -> test(testCase, scope)31         else -> {32            val dispatcher = UnconfinedTestDispatcher()33            logger.log { Pair(testCase.name.testName, "Switching context to StandardTestDispatcher: $dispatcher") }34            withContext(dispatcher + CoroutineName("wibble")) {35               test(testCase, scope.withCoroutineContext(dispatcher))36            }37         }...

TestCoroutineDispatcherInterceptorTest.kt

Source:TestCoroutineDispatcherInterceptorTest.kt

...7import io.kotest.core.test.TestCase8import io.kotest.core.test.TestResult9import io.kotest.core.test.TestType10import io.kotest.core.test.testCoroutineScheduler11import io.kotest.engine.test.interceptors.TestDispatcherInterceptor12import io.kotest.engine.test.scopes.NoopTestScope13import io.kotest.matchers.booleans.shouldBeTrue14import io.kotest.matchers.nulls.shouldNotBeNull15import kotlinx.coroutines.ExperimentalCoroutinesApi16import kotlin.time.Duration.Companion.milliseconds17@ExperimentalStdlibApi18@ExperimentalCoroutinesApi19class TestCoroutineDispatcherInterceptorTest : FunSpec() {20   init {21      test("TestCoroutineDispatcherInterceptor should install a DelayController") {22         val tc = TestCase(23            InvocationCountCheckInterceptorTest::class.toDescriptor().append("foo"),24            TestName("foo"),25            InvocationCountCheckInterceptorTest(),26            {},27            sourceRef(),28            TestType.Test,29         )30         var fired = false31         TestDispatcherInterceptor().intercept(tc, NoopTestScope(tc, coroutineContext)) { _, context ->32            context.testCoroutineScheduler.shouldNotBeNull()33            fired = true34            TestResult.Success(0.milliseconds)35         }36         fired.shouldBeTrue()37      }38   }39}

TestDispatcherInterceptor

Using AI Code Generation

1val listener = object : TestEngineListener {2override fun engineFinished(t: List<Throwable>) {3println("Engine finished with $t")4}5override fun engineStarted(classes: List<KClass<*>>) {6println("Engine started with $classes")7}8override fun specFinished(kclass: KClass<*>, t: Throwable?, results: Map<TestCase, TestResult>) {9println("Spec finished with $t")10}11override fun specStarted(kclass: KClass<*>) {12println("Spec started with $kclass")13}14}15val engine = TestEngine(listOf(TestDispatcherInterceptor()))16engine.execute(listOf(MySpec::class), listener)

TestDispatcherInterceptor

Using AI Code Generation

1    interceptors(TestDispatcherInterceptor)2    interceptors(TestCoroutineDispatcherInterceptor)3    interceptors(TestCoroutineExceptionHandlerInterceptor)4    interceptors(TestCoroutineScopeInterceptor)5    interceptors(TestDslStateInterceptor)6    interceptors(TestTimeoutInterceptor)7    interceptors(TestWithConfigInterceptor)8    interceptors(TestWithExtensionsInterceptor)9    interceptors(TestWithInvocationInterceptor)10    interceptors(TestWithLifecycleInterceptor)11    interceptors(TestWithProjectConfigInterceptor)12    interceptors(TestWithTestNameInterceptor)13    interceptors(TestWithTestCaseConfigInterceptor)14    interceptors(TestWithTestContextInterceptor)15    interceptors(TestWithTestDslStateInterceptor)16    interceptors(TestWithTestScopeInterceptor)

TestDispatcherInterceptor

Using AI Code Generation

1val engine = TestEngineLauncher()  2.withTestEngine(KotestEngine())  3.withInterceptor(TestDispatcherInterceptor())  4.withListener(TestEngineListener())  5.build()  6engine.execute(listOf(MySpec::class))

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