Fixes

kotlinx-coroutines-test/README.md

@@ -114,7 +114,7 @@ suspend fun bar() {}
 ```
 
 `runBlockingTest` will auto-progress virtual time until all coroutines are completed before returning. If any coroutines
-are not able to complete, an [UncompletedCoroutinesError] will be thrown.
+are not able to complete, an `AssertionError` will be thrown.
 
 *Note:* The default eager behavior of [runBlockingTest] will ignore [CoroutineStart] parameters.
 
@@ -148,7 +148,7 @@ suspend fun CoroutineScope.foo() {
 *Note:* `runBlockingTest` will always attempt to auto-progress time until all coroutines are completed just before 
 exiting. This is a convenience to avoid having to call [advanceUntilIdle][DelayController.advanceUntilIdle] 
 as the last line of many common test cases.
-If any coroutines cannot complete by advancing time, an [UncompletedCoroutinesError] is thrown.
+If any coroutines cannot complete by advancing time, an `AssertionError` is thrown.
 
 ### Testing `withTimeout` using `runBlockingTest`
 
@@ -447,7 +447,6 @@ If you have any suggestions for improvements to this experimental API please sha
 
 [setMain]: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-test/kotlinx.coroutines.test/set-main.html
 [runBlockingTest]: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-test/kotlinx.coroutines.test/run-blocking-test.html
-[UncompletedCoroutinesError]: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-test/kotlinx.coroutines.test/-uncompleted-coroutines-error/index.html
 [DelayController]: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-test/kotlinx.coroutines.test/-delay-controller/index.html
 [DelayController.advanceUntilIdle]: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-test/kotlinx.coroutines.test/-delay-controller/advance-until-idle.html
 [DelayController.pauseDispatcher]: https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-test/kotlinx.coroutines.test/-delay-controller/pause-dispatcher.html

kotlinx-coroutines-test/api/kotlinx-coroutines-test.api

@@ -58,10 +58,6 @@ public abstract interface class kotlinx/coroutines/test/TestCoroutineScope : kot
 	public abstract fun getTestScheduler ()Lkotlinx/coroutines/test/TestCoroutineScheduler;
 }
 
-public final class kotlinx/coroutines/test/TestCoroutineScope$DefaultImpls {
-	public static fun getTestScheduler (Lkotlinx/coroutines/test/TestCoroutineScope;)Lkotlinx/coroutines/test/TestCoroutineScheduler;
-}
-
 public final class kotlinx/coroutines/test/TestCoroutineScopeKt {
 	public static final fun TestCoroutineScope (Lkotlin/coroutines/CoroutineContext;)Lkotlinx/coroutines/test/TestCoroutineScope;
 	public static synthetic fun TestCoroutineScope$default (Lkotlin/coroutines/CoroutineContext;ILjava/lang/Object;)Lkotlinx/coroutines/test/TestCoroutineScope;
@@ -92,7 +88,3 @@ public abstract interface class kotlinx/coroutines/test/UncaughtExceptionCaptor
 	public abstract fun getUncaughtExceptions ()Ljava/util/List;
 }
 
-public final class kotlinx/coroutines/test/UncompletedCoroutinesError : java/lang/AssertionError {
-	public fun <init> (Ljava/lang/String;)V
-}
-

kotlinx-coroutines-test/common/src/DelayController.kt

@@ -84,11 +84,11 @@ public interface DelayController {
     /**
      * Call after test code completes to ensure that the dispatcher is properly cleaned up.
      *
-     * @throws UncompletedCoroutinesError if any pending tasks are active, however it will not throw for suspended
+     * @throws AssertionError if any pending tasks are active, however it will not throw for suspended
      * coroutines.
      */
     @ExperimentalCoroutinesApi
-    @Throws(UncompletedCoroutinesError::class)
+    @Throws(AssertionError::class)
     public fun cleanupTestCoroutines()
 
     /**
@@ -123,13 +123,6 @@ public interface DelayController {
     public fun resumeDispatcher()
 }
 
-/**
- * Thrown when a test has completed and there are tasks that are not completed or cancelled.
- */
-// todo: maybe convert into non-public class in 1.3.0 (need use-cases for a public exception type)
-@ExperimentalCoroutinesApi
-public class UncompletedCoroutinesError(message: String): AssertionError(message)
-
 internal interface SchedulerAsDelayController: DelayController {
     public val scheduler: TestCoroutineScheduler
 

kotlinx-coroutines-test/common/src/TestBuilders.kt

@@ -34,7 +34,7 @@ import kotlin.coroutines.*
  *
  * Unhandled exceptions thrown by coroutines in the test will be re-thrown at the end of the test.
  *
- * @throws UncompletedCoroutinesError If the [testBody] does not complete (or cancel) all coroutines that it launches
+ * @throws AssertionError If the [testBody] does not complete (or cancel) all coroutines that it launches
  * (including coroutines suspended on join/await).
  *
  * @param context additional context elements. If [context] contains [CoroutineDispatcher] or [CoroutineExceptionHandler],

kotlinx-coroutines-test/common/src/TestCoroutineScheduler.kt

@@ -24,10 +24,11 @@ import kotlin.jvm.*
  */
 @ExperimentalCoroutinesApi
 // TODO: maybe make this a `TimeSource`?
-public class TestCoroutineScheduler: AbstractCoroutineContextElement(TestCoroutineScheduler), CoroutineContext.Element {
+public class TestCoroutineScheduler : AbstractCoroutineContextElement(TestCoroutineScheduler),
+    CoroutineContext.Element {
 
     /** @suppress */
-    public companion object Key: CoroutineContext.Key<TestCoroutineScheduler>
+    public companion object Key : CoroutineContext.Key<TestCoroutineScheduler>
 
     /** This heap stores the knowledge about which dispatchers are interested in which moments of virtual time. */
     // TODO: all the synchronization is done via a separate lock, so a non-thread-safe priority queue can be used.
@@ -55,7 +56,7 @@ public class TestCoroutineScheduler: AbstractCoroutineContextElement(TestCorouti
         dispatcher: TestDispatcher,
         timeDeltaMillis: Long,
         marker: T,
-        isCancelled : (T) -> Boolean
+        isCancelled: (T) -> Boolean
     ): DisposableHandle {
         require(timeDeltaMillis >= 0) { "Attempted scheduling an event earlier in time (with the time delta $timeDeltaMillis)" }
         val count = count.getAndIncrement()

kotlinx-coroutines-test/common/src/TestCoroutineScope.kt

@@ -11,13 +11,13 @@ import kotlin.coroutines.*
  * A scope which provides detailed control over the execution of coroutines for tests.
  */
 @ExperimentalCoroutinesApi
-public interface TestCoroutineScope: CoroutineScope, UncaughtExceptionCaptor {
+public sealed interface TestCoroutineScope: CoroutineScope, UncaughtExceptionCaptor {
     /**
      * Call after the test completes.
      * Calls [UncaughtExceptionCaptor.cleanupTestCoroutinesCaptor] and [DelayController.cleanupTestCoroutines].
      *
      * @throws Throwable the first uncaught exception, if there are any uncaught exceptions.
-     * @throws UncompletedCoroutinesError if any pending tasks are active, however it will not throw for suspended
+     * @throws AssertionError if any pending tasks are active, however it will not throw for suspended
      * coroutines.
      */
     @ExperimentalCoroutinesApi
@@ -28,8 +28,6 @@ public interface TestCoroutineScope: CoroutineScope, UncaughtExceptionCaptor {
      */
     @ExperimentalCoroutinesApi
     public val testScheduler: TestCoroutineScheduler
-        get() = coroutineContext[TestCoroutineScheduler]
-            ?: throw UnsupportedOperationException("This scope does not have a TestCoroutineScheduler linked to it")
 }
 
 private class TestCoroutineScopeImpl (
@@ -158,3 +156,9 @@ public fun TestCoroutineScope.resumeDispatcher() {
 private val TestCoroutineScope.delayControllerForPausing: DelayController
     get() = coroutineContext.delayController
         ?: throw IllegalStateException("This scope isn't able to pause its dispatchers")
+
+/**
+ * Thrown when a test has completed and there are tasks that are not completed or cancelled.
+ */
+@ExperimentalCoroutinesApi
+internal class UncompletedCoroutinesError(message: String): AssertionError(message)

kotlinx-coroutines-test/common/src/TestDispatcher.kt

@@ -18,7 +18,6 @@ public abstract class TestDispatcher: CoroutineDispatcher(), Delay {
     public abstract val scheduler: TestCoroutineScheduler
 
     /** Notifies the dispatcher that it should process a single event marked with [marker] happening at time [time]. */
-    @ExperimentalCoroutinesApi
     internal abstract fun processEvent(time: Long, marker: Any)
 
     /** @suppress */