Take number of CPU cores into account in BlockingCoroutineDispatcherTest (#2737)

Author: qwwdfsad

kotlinx-coroutines-core/jvm/test/scheduling/BlockingCoroutineDispatcherTest.kt

@@ -101,7 +101,7 @@ class BlockingCoroutineDispatcherTest : SchedulerTestBase() {
         firstBarrier.await()
         secondBarrier.await()
         blockingTasks.joinAll()
-        checkPoolThreadsCreated(21..22)
+        checkPoolThreadsCreated(21 /* blocking tasks + 1 for CPU */..20 + CORES_COUNT)
     }
 
     @Test
@@ -122,7 +122,7 @@ class BlockingCoroutineDispatcherTest : SchedulerTestBase() {
         barrier.await()
         blockingTasks.joinAll()
         // There may be race when multiple CPU threads are trying to lazily created one more
-        checkPoolThreadsCreated(104..120)
+        checkPoolThreadsCreated(101..100 + CORES_COUNT)
     }
 
     @Test

kotlinx-coroutines-core/jvm/test/scheduling/SchedulerTestBase.kt

@@ -39,14 +39,6 @@ abstract class SchedulerTestBase : TestBase() {
             )
         }
 
-        /**
-         * Asserts that any number of pool worker threads in [range] exists at the time of method invocation
-         */
-        fun checkPoolThreadsExist(range: IntRange) {
-            val threads = Thread.getAllStackTraces().keys.asSequence().filter { it is CoroutineScheduler.Worker }.count()
-            assertTrue(threads in range, "Expected threads in $range interval, but has $threads")
-        }
-
         private fun maxSequenceNumber(): Int? {
             return Thread.getAllStackTraces().keys.asSequence().filter { it is CoroutineScheduler.Worker }
                 .map { sequenceNumber(it.name) }.maxOrNull()