[LYN-2255] Made PrefabTestFixture have the prefab system enabled so that the duplicate tests pass on Jenkins (they rely on the PrefabEditorEntityOwnershipInterface being registered).

Code/Framework/AzToolsFramework/AzToolsFramework/Prefab/PrefabPublicHandler.cpp

@@ -705,7 +705,7 @@ namespace AzToolsFramework
 
                 if (!success)
                 {
-                    return AZ::Failure(AZStd::string("DuplicateEntitiesInInstance"));
+                    return AZ::Failure(AZStd::string("Cannot duplicate multiple entities belonging to different instances with one operation"));
                 }
 
                 // Make a copy of our before instance DOM where we will add our duplicated entities

Code/Framework/AzToolsFramework/AzToolsFramework/UnitTest/AzToolsFrameworkTestHelpers.h

@@ -138,7 +138,7 @@ namespace UnitTest
             if (!GetApplication())
             {
                 // Create & Start a new ToolsApplication if there's no existing one
-                m_app = AZStd::make_unique<ToolsTestApplication>("ToolsApplication");
+                m_app = CreateTestApplication();
                 m_app->Start(AzFramework::Application::Descriptor());
             }
 
@@ -216,6 +216,12 @@ namespace UnitTest
         TestEditorActions m_editorActions;
         ToolsApplicationMessageHandler m_messageHandler; // used to suppress trace messages in test output
 
+        // Override this if your test fixture needs to use a custom TestApplication
+        virtual AZStd::unique_ptr<ToolsTestApplication> CreateTestApplication()
+        {
+            return AZStd::make_unique<ToolsTestApplication>("ToolsApplication");
+        }
+
     private:
         AZStd::unique_ptr<ToolsTestApplication> m_app;
     };

Code/Framework/AzToolsFramework/Tests/Prefab/PrefabTestFixture.cpp

@@ -20,6 +20,17 @@
 
 namespace UnitTest
 {
+    PrefabTestToolsApplication::PrefabTestToolsApplication(AZStd::string appName)
+        : ToolsTestApplication(AZStd::move(appName))
+    {
+    }
+
+    bool PrefabTestToolsApplication::IsPrefabSystemEnabled() const
+    {
+        // Make sure our prefab tests always run with prefabs enabled
+        return true;
+    }
+
     void PrefabTestFixture::SetUpEditorFixtureImpl()
     {
         // Acquire the system entity
@@ -44,6 +55,11 @@ namespace UnitTest
         GetApplication()->RegisterComponentDescriptor(PrefabTestComponent::CreateDescriptor());
     }
 
+    AZStd::unique_ptr<ToolsTestApplication> PrefabTestFixture::CreateTestApplication()
+    {
+        return AZStd::make_unique<PrefabTestToolsApplication>("PrefabTestApplication");
+    }
+
     AZ::Entity* PrefabTestFixture::CreateEntity(const char* entityName, const bool shouldActivate)
     {
         // Circumvent the EntityContext system and generate a new entity with a transformcomponent

Code/Framework/AzToolsFramework/Tests/Prefab/PrefabTestFixture.h

@@ -31,6 +31,16 @@ namespace UnitTest
     using namespace AzToolsFramework::Prefab;
     using namespace PrefabTestUtils;
 
+    class PrefabTestToolsApplication
+        : public ToolsTestApplication
+    {
+    public:
+        PrefabTestToolsApplication(AZStd::string appName);
+
+        // Make sure our prefab tests always run with prefabs enabled
+        bool IsPrefabSystemEnabled() const override;
+    };
+
     class PrefabTestFixture
         : public ToolsApplicationFixture,
           public UnitTest::TraceBusRedirector
@@ -45,6 +55,8 @@ namespace UnitTest
 
         void SetUpEditorFixtureImpl() override;
 
+        AZStd::unique_ptr<ToolsTestApplication> CreateTestApplication() override;
+
         AZ::Entity* CreateEntity(const char* entityName, const bool shouldActivate = true);
 
         void CompareInstances(const Instance& instanceA, const Instance& instanceB, bool shouldCompareLinkIds = true,