From b07924624ef29cff971565af59f8f125f087d529 Mon Sep 17 00:00:00 2001
From: Egor Ushakov <egor.ushakov@jetbrains.com>
Date: Tue, 4 Mar 2025 13:49:11 +0100
Subject: [PATCH] [debugger] fixing flaky tests

GitOrigin-RevId: 6325d5f32e460156ad8fa4ab31275233a69903e5
---
 .../engine/DebuggerManagerThreadImpl.kt       |  5 ++-
 .../intellij/debugger/impl/InvokeThread.java  | 37 ++++++++++++-------
 2 files changed, 26 insertions(+), 16 deletions(-)

diff --git a/java/debugger/impl/src/com/intellij/debugger/engine/DebuggerManagerThreadImpl.kt b/java/debugger/impl/src/com/intellij/debugger/engine/DebuggerManagerThreadImpl.kt
index 6592188a864b..b85f41874f89 100644
--- a/java/debugger/impl/src/com/intellij/debugger/engine/DebuggerManagerThreadImpl.kt
+++ b/java/debugger/impl/src/com/intellij/debugger/engine/DebuggerManagerThreadImpl.kt
@@ -166,9 +166,10 @@ class DebuggerManagerThreadImpl @ApiStatus.Internal @JvmOverloads constructor(
         {
           if (currentCommand === myEvents.currentEvent) {
             // if current command is still in progress, cancel it
-            currentRequest.requestStop()
+            val request = currentRequest
+            request.requestStop()
             try {
-              currentRequest.join()
+              request.join()
             }
             catch (_: InterruptedException) {
             }
diff --git a/java/debugger/impl/src/com/intellij/debugger/impl/InvokeThread.java b/java/debugger/impl/src/com/intellij/debugger/impl/InvokeThread.java
index 5ada023b417b..f26020df1c89 100644
--- a/java/debugger/impl/src/com/intellij/debugger/impl/InvokeThread.java
+++ b/java/debugger/impl/src/com/intellij/debugger/impl/InvokeThread.java
@@ -118,7 +118,7 @@ public abstract class InvokeThread<E extends PrioritizedTask> {
 
   protected final EventQueue<E> myEvents;
 
-  private volatile WorkerThreadRequest<E> myCurrentRequest = null;
+  private WorkerThreadRequest<E> myCurrentRequest = null;
 
   public InvokeThread() {
     myEvents = new EventQueue<>(PrioritizedTask.Priority.values().length);
@@ -128,15 +128,19 @@ public abstract class InvokeThread<E extends PrioritizedTask> {
   protected abstract void processEvent(@NotNull E e);
 
   protected void startNewWorkerThread() {
-    assertCurrentThreadIsActive();
+    // myCurrentRequest has to be updated atomically with calling setRequestFuture
+    // otherwise we may have asserts triggering inside workerRequest.requestStop etc.
+    synchronized (this) {
+      assertCurrentThreadIsActive();
 
-    final WorkerThreadRequest<E> workerRequest = new WorkerThreadRequest<>(this);
-    WorkerThreadRequest<E> oldRequest = myCurrentRequest; // just for logging
-    myCurrentRequest = workerRequest;
-    if (LOG.isDebugEnabled()) {
-      LOG.debug("Started new worker thread request " + workerRequest + ", was " + oldRequest);
+      final WorkerThreadRequest<E> workerRequest = new WorkerThreadRequest<>(this);
+      WorkerThreadRequest<E> oldRequest = myCurrentRequest; // just for logging
+      myCurrentRequest = workerRequest;
+      if (LOG.isDebugEnabled()) {
+        LOG.debug("Started new worker thread request " + workerRequest + ", was " + oldRequest);
+      }
+      workerRequest.setRequestFuture(ApplicationManager.getApplication().executeOnPooledThread(workerRequest));
     }
-    workerRequest.setRequestFuture(ApplicationManager.getApplication().executeOnPooledThread(workerRequest));
   }
 
   protected static boolean assertCurrentThreadIsActive() {
@@ -258,18 +262,23 @@ public abstract class InvokeThread<E extends PrioritizedTask> {
   }
 
   protected void switchToRequest(WorkerThreadRequest newRequest) {
-    final WorkerThreadRequest currentThreadRequest = getCurrentThreadRequest();
-    LOG.assertTrue(currentThreadRequest != null);
-    myCurrentRequest = newRequest;
-    if (LOG.isDebugEnabled()) {
-      LOG.debug("Switched current request from " + currentThreadRequest + " to " + newRequest);
+    WorkerThreadRequest currentThreadRequest;
+    synchronized (this) {
+      currentThreadRequest = getCurrentThreadRequest();
+      LOG.assertTrue(currentThreadRequest != null);
+      myCurrentRequest = newRequest;
+      if (LOG.isDebugEnabled()) {
+        LOG.debug("Switched current request from " + currentThreadRequest + " to " + newRequest);
+      }
     }
 
     currentThreadRequest.requestStop();
   }
 
   public WorkerThreadRequest<E> getCurrentRequest() {
-    return myCurrentRequest;
+    synchronized (this) {
+      return myCurrentRequest;
+    }
   }
 
   public static WorkerThreadRequest<?> getCurrentThreadRequest() {