From 9aacd136b88fd41f0bf872a882a6db440a088ca2 Mon Sep 17 00:00:00 2001
From: Simon Walton <simon@highfidelity.io>
Date: Wed, 14 Aug 2019 13:51:40 -0700
Subject: [PATCH] Add blocking to script unload for client entity-scripts

---
 interface/src/Application.cpp                          | 1 -
 libraries/entities-renderer/src/EntityTreeRenderer.cpp | 2 +-
 libraries/script-engine/src/ScriptEngine.cpp           | 5 +++--
 libraries/script-engine/src/ScriptEngine.h             | 3 ++-
 4 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index 481975caac..0df377a4f2 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -2761,7 +2761,6 @@ void Application::cleanupBeforeQuit() {
     }
 
     getEntities()->shutdown(); // tell the entities system we're shutting down, so it will stop running scripts
-    getEntities()->clear();
 
     // Clear any queued processing (I/O, FBX/OBJ/Texture parsing)
     QThreadPool::globalInstance()->clear();
diff --git a/libraries/entities-renderer/src/EntityTreeRenderer.cpp b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
index 305384361d..fd82567a94 100644
--- a/libraries/entities-renderer/src/EntityTreeRenderer.cpp
+++ b/libraries/entities-renderer/src/EntityTreeRenderer.cpp
@@ -253,7 +253,7 @@ void EntityTreeRenderer::clear() {
     // unload and stop the engine
     if (_entitiesScriptEngine) {
         // do this here (instead of in deleter) to avoid marshalling unload signals back to this thread
-        _entitiesScriptEngine->unloadAllEntityScripts();
+        _entitiesScriptEngine->unloadAllEntityScripts(true);
         _entitiesScriptEngine->stop();
     }
 
diff --git a/libraries/script-engine/src/ScriptEngine.cpp b/libraries/script-engine/src/ScriptEngine.cpp
index 5e20f06a7f..6808da2e1a 100644
--- a/libraries/script-engine/src/ScriptEngine.cpp
+++ b/libraries/script-engine/src/ScriptEngine.cpp
@@ -2470,13 +2470,14 @@ QList<EntityItemID> ScriptEngine::getListOfEntityScriptIDs() {
     return _entityScripts.keys();
 }
 
-void ScriptEngine::unloadAllEntityScripts() {
+void ScriptEngine::unloadAllEntityScripts(bool blockingCall) {
     if (QThread::currentThread() != thread()) {
 #ifdef THREAD_DEBUGGING
         qCDebug(scriptengine) << "*** WARNING *** ScriptEngine::unloadAllEntityScripts() called on wrong thread [" << QThread::currentThread() << "], invoking on correct thread [" << thread() << "]";
 #endif
 
-        QMetaObject::invokeMethod(this, "unloadAllEntityScripts");
+        QMetaObject::invokeMethod(this, "unloadAllEntityScripts",
+            blockingCall ? Qt::BlockingQueuedConnection : Qt::QueuedConnection);
         return;
     }
 #ifdef THREAD_DEBUGGING
diff --git a/libraries/script-engine/src/ScriptEngine.h b/libraries/script-engine/src/ScriptEngine.h
index 52ece63dc2..d738b13ecc 100644
--- a/libraries/script-engine/src/ScriptEngine.h
+++ b/libraries/script-engine/src/ScriptEngine.h
@@ -578,9 +578,10 @@ public:
 
     /**jsdoc
      * @function Script.unloadAllEntityScripts
+     * @param {boolean} [blockingCall=false] - Wait for completion if call moved to another thread.
      * @deprecated This function is deprecated and will be removed.
      */
-    Q_INVOKABLE void unloadAllEntityScripts();
+    Q_INVOKABLE void unloadAllEntityScripts(bool blockingCall = false);
 
     /**jsdoc
      * Calls a method in an entity script.