How to use FixedThreadCoroutineDispatcherFactory class of io.kotest.engine.concurrency package

Best Kotest code snippet using io.kotest.engine.concurrency.FixedThreadCoroutineDispatcherFactory

FixedThreadCoroutineDispatcherFactory.kt

Source:FixedThreadCoroutineDispatcherFactory.kt

...25 *26 * As factories can be shared across specs, it is possible to create an instance of this factory27 * and assign it to be used by several specs independently of others.28 */29class FixedThreadCoroutineDispatcherFactory(30   threads: Int,31   private val affinity: Boolean,32) : CoroutineDispatcherFactory {33   private val logger = Logger(FixedThreadCoroutineDispatcherFactory::class)34   private val dispatchers = List(threads) { Executors.newSingleThreadExecutor().asCoroutineDispatcher() }35   override suspend fun <T> withDispatcher(testCase: TestCase, f: suspend () -> T): T {36      val resolvedAffinity = testCase.spec.dispatcherAffinity ?: testCase.spec.dispatcherAffinity() ?: affinity37      logger.log { Pair(testCase.name.testName, "affinity=$resolvedAffinity") }38      // if dispatcher affinity is set to true, we pick a dispatcher for the spec and stick with it39      // otherwise each test just gets a random dispatcher40      val dispatcher = when (resolvedAffinity) {41         true -> dispatcherFor(testCase.spec::class)42         else -> dispatchers.random()43      }44      logger.log { Pair(testCase.name.testName, "Switching dispatcher to $dispatcher") }45      return withContext(dispatcher) {46         f()47      }...

coroutineDispatcherFactoryInterceptor.kt

Source:coroutineDispatcherFactoryInterceptor.kt

2import io.kotest.core.concurrency.CoroutineDispatcherFactory3import io.kotest.core.test.TestCase4import io.kotest.core.test.TestResult5import io.kotest.core.test.TestScope6import io.kotest.engine.concurrency.FixedThreadCoroutineDispatcherFactory7import io.kotest.engine.test.scopes.withCoroutineContext8import io.kotest.mpp.Logger9import kotlinx.coroutines.CoroutineDispatcher10import kotlinx.coroutines.test.TestCoroutineDispatcher11import kotlinx.coroutines.test.TestDispatcher12import kotlin.coroutines.coroutineContext13@ExperimentalStdlibApi14internal actual fun coroutineDispatcherFactoryInterceptor(15   defaultCoroutineDispatcherFactory: CoroutineDispatcherFactory16): TestExecutionInterceptor = CoroutineDispatcherFactoryInterceptor(defaultCoroutineDispatcherFactory)17/**18 * Switches execution onto a dispatcher provided by a [CoroutineDispatcherFactory].19 *20 * If the coroutine is an instance of [TestDispatcher] then the coroutine will not be changed.21 */22@ExperimentalStdlibApi23internal class CoroutineDispatcherFactoryInterceptor(24   private val defaultCoroutineDispatcherFactory: CoroutineDispatcherFactory25) : TestExecutionInterceptor {26   private val logger = Logger(CoroutineDispatcherFactoryInterceptor::class)27   override suspend fun intercept(28      testCase: TestCase,29      scope: TestScope,30      test: suspend (TestCase, TestScope) -> TestResult31   ): TestResult {32      val currentDispatcher = coroutineContext[CoroutineDispatcher]33      // we don't override if we've set a test dispatcher on this already34      return if (currentDispatcher is TestDispatcher) {35         test(testCase, scope)36      } else {37         val userFactory = testCase.spec.coroutineDispatcherFactory ?: testCase.spec.coroutineDispatcherFactory()38         val threads = testCase.spec.threads ?: testCase.spec.threads() ?: 139         logger.log { Pair(testCase.name.testName, "userFactory=$userFactory; threads=$threads") }40         val f = when {41            userFactory != null -> userFactory42            threads > 1 -> FixedThreadCoroutineDispatcherFactory(threads, false)43            else -> defaultCoroutineDispatcherFactory44         }45         logger.log { Pair(testCase.name.testName, "Switching dispatcher using factory $f") }46         f.withDispatcher(testCase) {47            test(testCase, scope.withCoroutineContext(coroutineContext))48         }49      }50   }51}...

DefaultCoroutineDispatcherFactory.kt

Source:DefaultCoroutineDispatcherFactory.kt

1package io.kotest.engine.concurrency2import io.kotest.core.concurrency.CoroutineDispatcherFactory3import io.kotest.core.config.ProjectConfiguration4internal actual fun defaultCoroutineDispatcherFactory(configuration: ProjectConfiguration): CoroutineDispatcherFactory =5   FixedThreadCoroutineDispatcherFactory(configuration.parallelism, configuration.dispatcherAffinity)...

FixedThreadCoroutineDispatcherFactory

Using AI Code Generation

1+class FixedThreadCoroutineDispatcherFactoryTest : WordSpec({2+    "FixedThreadCoroutineDispatcherFactory" should {3+        "create fixed thread dispatcher with given number of threads" {4+            val dispatcher = FixedThreadCoroutineDispatcherFactory(4).create()5+        }6+    }7+})8+import io.kotest.core.concurrency.CoroutineDispatcherFactory9+import kotlinx.coroutines.CoroutineDispatcher10+import kotlinx.coroutines.asCoroutineDispatcher11+import java.util.concurrent.Executors12+class SingleThreadCoroutineDispatcherFactory : CoroutineDispatcherFactory {13+    override fun create(): CoroutineDispatcher {14+        return Executors.newSingleThreadExecutor().asCoroutineDispatcher()15+    }16+}17+import io.kotest

FixedThreadCoroutineDispatcherFactory

Using AI Code Generation

1+class MyTest : FunSpec({2+   val dispatcher = FixedThreadCoroutineDispatcherFactory(4).create()3+   val scope = CoroutineScope(dispatcher)4+   test("some test") {5+   }6+})7+class MyTest : CoroutineTest() {8+      get() = TestCoroutineDispatcher()9+   test("some test") {

FixedThreadCoroutineDispatcherFactory

Using AI Code Generation

1    val dispatcher = FixedThreadCoroutineDispatcherFactory(4).create()2    withCoroutineContext(dispatcher) {3    }4    class MySpec : FunSpec({5      listeners(MyListener())6    })7    registerListener(MyListener())

FixedThreadCoroutineDispatcherFactory

Using AI Code Generation

1val dispatcher = FixedThreadCoroutineDispatcherFactory(2)2class MySpec : FunSpec() {3   override fun extensions(): List<Extension> = listOf(4      object : TestContext {5         override fun afterTest(testCase: TestCase, result: TestResult) {6            println(testCase.spec.configuration)7         }8      }9}10class MySpec : FunSpec() {11   override fun extensions(): List<Extension> = listOf(12      object : TestScope {13         override fun beforeEach(testCase: TestCase) {14            println(testCase.spec)15         }16      }17}18class MySpec : FunSpec()

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