From bcfe903c871f30242d0be298fb6655d57e89bfeb Mon Sep 17 00:00:00 2001
From: Nikolay Rykunov <nikolay.rykunov@jetbrains.com>
Date: Thu, 10 Oct 2024 11:21:39 +0200
Subject: [PATCH] [debugger-rd] IJPL-160146: Wrap XStackFrame in Ref, so
 StateFlow will use reference equity

GitOrigin-RevId: 6523a64381f2ba92e46d435a84cc24478df7f1f3
---
 .../xdebugger/impl/XDebugSessionImpl.java     | 27 +++++++++----------
 .../impl/XDebuggerActiveSessionController.kt  |  3 ++-
 2 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java
index 14704feffb00..55adb44cdd2a 100644
--- a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java
+++ b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java
@@ -27,6 +27,7 @@ import com.intellij.openapi.ui.MessageType;
 import com.intellij.openapi.util.Comparing;
 import com.intellij.openapi.util.Disposer;
 import com.intellij.openapi.util.Pair;
+import com.intellij.openapi.util.Ref;
 import com.intellij.platform.util.coroutines.CoroutineScopeKt;
 import com.intellij.ui.AppUIUtil;
 import com.intellij.util.EventDispatcher;
@@ -56,10 +57,7 @@ import com.intellij.xdebugger.stepping.XSmartStepIntoHandler;
 import com.intellij.xdebugger.stepping.XSmartStepIntoVariant;
 import kotlin.coroutines.EmptyCoroutineContext;
 import kotlinx.coroutines.CoroutineScope;
-import kotlinx.coroutines.flow.FlowKt;
-import kotlinx.coroutines.flow.MutableStateFlow;
-import kotlinx.coroutines.flow.StateFlow;
-import kotlinx.coroutines.flow.StateFlowKt;
+import kotlinx.coroutines.flow.*;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.Nls;
 import org.jetbrains.annotations.NotNull;
@@ -113,7 +111,7 @@ public final class XDebugSessionImpl implements XDebugSession {
   private final List<AnAction> myExtraActions = new SmartList<>();
   private ConsoleView myConsoleView;
   private final Icon myIcon;
-  private final MutableStateFlow<@Nullable XStackFrame> myCurrentStackFrame = createMutableStateFlow(null);
+  private final MutableStateFlow<@NotNull Ref<@Nullable XStackFrame>> myCurrentStackFrame = createMutableStateFlow(Ref.create(null));
 
   private volatile boolean breakpointsInitialized;
   private long myUserRequestStart;
@@ -269,14 +267,15 @@ public final class XDebugSessionImpl implements XDebugSession {
     return myPaused.get();
   }
 
+  // returns Ref to skip StateFlow's equals check
   @ApiStatus.Internal
-  public StateFlow<XStackFrame> getCurrentStackFrameFlow() {
+  public StateFlow<Ref<XStackFrame>> getCurrentStackFrameFlow() {
     return myCurrentStackFrame;
   }
 
   @Override
   public @Nullable XStackFrame getCurrentStackFrame() {
-    return myCurrentStackFrame.getValue();
+    return myCurrentStackFrame.getValue().get();
   }
 
   public @Nullable XExecutionStack getCurrentExecutionStack() {
@@ -290,7 +289,7 @@ public final class XDebugSessionImpl implements XDebugSession {
 
   @Override
   public @Nullable XSourcePosition getCurrentPosition() {
-    return getFrameSourcePosition(myCurrentStackFrame.getValue());
+    return getFrameSourcePosition(myCurrentStackFrame.getValue().get());
   }
 
   @Override
@@ -672,7 +671,7 @@ public final class XDebugSessionImpl implements XDebugSession {
   private void clearPausedData() {
     mySuspendContext = null;
     myCurrentExecutionStack = null;
-    myCurrentStackFrame.setValue(null);
+    myCurrentStackFrame.setValue(Ref.create(null));
     myTopStackFrame = null;
     clearActiveNonLineBreakpoint();
     updateExecutionPosition();
@@ -687,8 +686,8 @@ public final class XDebugSessionImpl implements XDebugSession {
     // allowed only for the active session
     if (myDebuggerManager.getCurrentSession() == this) {
       boolean isTopFrame = isTopFrameSelected();
-      XSourcePosition mainSourcePosition = getFrameSourcePosition(myCurrentStackFrame.getValue(), XSourceKind.MAIN);
-      XSourcePosition alternativeSourcePosition = getFrameSourcePosition(myCurrentStackFrame.getValue(), XSourceKind.ALTERNATIVE);
+      XSourcePosition mainSourcePosition = getFrameSourcePosition(myCurrentStackFrame.getValue().get(), XSourceKind.MAIN);
+      XSourcePosition alternativeSourcePosition = getFrameSourcePosition(myCurrentStackFrame.getValue().get(), XSourceKind.ALTERNATIVE);
       myExecutionPointManager.setExecutionPoint(mainSourcePosition, alternativeSourcePosition, isTopFrame, navigationSourceKind);
       updateExecutionPointGutterIconRenderer();
     }
@@ -717,9 +716,9 @@ public final class XDebugSessionImpl implements XDebugSession {
   public void setCurrentStackFrame(@NotNull XExecutionStack executionStack, @NotNull XStackFrame frame, boolean isTopFrame) {
     if (mySuspendContext == null) return;
 
-    boolean frameChanged = myCurrentStackFrame.getValue() != frame;
+    boolean frameChanged = myCurrentStackFrame.getValue().get() != frame;
     myCurrentExecutionStack = executionStack;
-    myCurrentStackFrame.setValue(frame);
+    myCurrentStackFrame.setValue(Ref.create(frame));
     myIsTopFrame = isTopFrame;
 
     if (frameChanged) {
@@ -942,7 +941,7 @@ public final class XDebugSessionImpl implements XDebugSession {
     mySuspendContext = suspendContext;
     myCurrentExecutionStack = suspendContext.getActiveExecutionStack();
     XStackFrame newCurrentStackFrame = myCurrentExecutionStack != null ? myCurrentExecutionStack.getTopFrame() : null;
-    myCurrentStackFrame.setValue(newCurrentStackFrame);
+    myCurrentStackFrame.setValue(Ref.create(newCurrentStackFrame));
     myIsTopFrame = true;
     myTopStackFrame = newCurrentStackFrame;
     XSourcePosition topFramePosition = getTopFramePosition();
diff --git a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebuggerActiveSessionController.kt b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebuggerActiveSessionController.kt
index c1750f8590df..a8d72ef6bf8d 100644
--- a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebuggerActiveSessionController.kt
+++ b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebuggerActiveSessionController.kt
@@ -103,7 +103,8 @@ internal fun synchronizeActiveSessionWithDb(coroutineScope: CoroutineScope, proj
 
 private suspend fun synchronizeSessionEvaluatorWithDb(session: XDebugSessionImpl, sessionEntity: XDebuggerActiveSessionEntity) {
   // NB!: we assume that the current evaluator depends only on the current StackFrame
-  session.currentStackFrameFlow.collect { stackFrame ->
+  session.currentStackFrameFlow.collect { stackFrameRef ->
+    val stackFrame = stackFrameRef.get()
     withKernel {
       change {
         val currentEvaluator = stackFrame?.evaluator