more deterministic `IntersectionScopeTest.completed child does not le…

…ak through parent`

GitOrigin-RevId: 770b2345eb7ab7a1155eb82d431a5054226b9b6e

platform/platform-tests/testSrc/com/intellij/openapi/application/impl/util.kt

@@ -41,6 +41,12 @@ fun assertReferenced(root: Any, referenced: Any) {
   assertNotNull(foundObjects.find { it === referenced })
 }
 
+fun assertNotReferenced(root: Any, referenced: Any) {
+  LeakHunter.checkLeak(root, referenced::class.java) { potentialLeak ->
+    potentialLeak === referenced
+  }
+}
+
 /**
  * @see com.intellij.util.ui.UIUtil.pump
  */

platform/platform-tests/testSrc/com/intellij/util/IntersectionScopeTest.kt

@@ -1,9 +1,9 @@
 // Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.util
 
+import com.intellij.openapi.application.impl.assertNotReferenced
 import com.intellij.openapi.application.impl.assertReferenced
 import com.intellij.openapi.progress.timeoutRunBlocking
-import com.intellij.testFramework.LeakHunter
 import com.intellij.testFramework.junit5.TestApplication
 import kotlinx.coroutines.*
 import kotlinx.coroutines.sync.Semaphore
@@ -165,14 +165,13 @@ class IntersectionScopeTest {
   @Test
   fun `completed child does not leak through parent`(): Unit = timeoutRunBlocking {
     val parentJob = Job()
-    val childJob = launch(start = CoroutineStart.UNDISPATCHED) {
-      attachAsChildTo(CoroutineScope(parentJob))
-      awaitCancellation()
-    }
+    val childJob = Job()
+    CoroutineScope(childJob).attachAsChildTo(CoroutineScope(parentJob))
     assertReferenced(parentJob, childJob)
+    val childHandleJob = parentJob.children.single()
     childJob.cancel()
-    parentJob.children.single().join() // wait for completion of job which waits for completion of the child
-    LeakHunter.checkLeak(parentJob, childJob::class.java)
+    childHandleJob.join()
+    assertNotReferenced(parentJob, childJob)
   }
 }