Don't store the editor in the WingFetcher.

Plugins/UEWingman/Source/UEWingman/Handlers/GraphNode_Remove.h

@@ -53,8 +53,13 @@ public:
 		{
 			// Use the material editor's DeleteNodes to properly remove
 			// both the graph node and the underlying material expression.
-			IMaterialEditor* MatEditor = F.CastEditor<UMaterial, IMaterialEditor>();
+			UMaterial* Material = F.CastAsset<UMaterial>();
-			if (!MatEditor) return;
+			if (!Material) return;
+
+			IAssetEditorInstance* Editor = WingUtils::CheckOpenEditorForAsset(Material, WingOut::Stdout);
+			if (!Editor) return;
+
+			IMaterialEditor* MatEditor = static_cast<IMaterialEditor*>(Editor);
 			MatEditor->DeleteNodes({FoundNode});
 		}
 		else

Plugins/UEWingman/Source/UEWingman/Private/WingFetcher.cpp

@@ -18,7 +18,6 @@
 #include "WidgetBlueprint.h"
 #include "Blueprint/WidgetTree.h"
 #include "Components/Widget.h"
-#include "Subsystems/AssetEditorSubsystem.h"
 #include "WingServer.h"
 #include "WingManual.h"
 
@@ -54,7 +53,6 @@ WingFetcher& WingFetcher::SetError()
 	Obj.Reset();
 	ResultPin = nullptr;
 	OriginalAsset.Reset();
-	Editor = nullptr;
 	return *this;
 }
 
@@ -156,26 +154,20 @@ WingFetcher& WingFetcher::Asset(const FString& PackagePath)
 
 	OriginalAsset.Reset(Obj.Get());
 
-	// Open the editor for this asset (or bring it to front if already open).
+	// If this is a material, open the editor and get the transient copy.
-	UAssetEditorSubsystem* Sub = GEditor->GetEditorSubsystem<UAssetEditorSubsystem>();
+	// If it's not a material, try to open the editor, but it's okay if we can't.
-	if (!Sub || !Sub->OpenEditorForAsset(Obj.Get()))
-	{
-		Errors.Printf(TEXT("ERROR: Could not open editor for '%s'\n"), *PackagePath);
-		return SetError();
-	}
-	Editor = Sub->FindEditorForAsset(OriginalAsset.Get(), false);
-	if (!Editor)
-	{
-		Errors.Printf(TEXT("ERROR: Could not find editor instance for '%s'\n"), *PackagePath);
-		return SetError();
-	}
-
-	// If this is a material, use the editor's transient copy.
 	if (UMaterial* Mat = ::Cast<UMaterial>(Obj.Get()))
 	{
+		IAssetEditorInstance* Editor = WingUtils::CheckOpenEditorForAsset(OriginalAsset.Get(), Errors);
+		if (!Editor) return SetError();
 		IMaterialEditor *MatEditor = static_cast<IMaterialEditor*>(Editor);
 		SetObj(MatEditor->GetMaterialInterface()->GetBaseMaterial());
 	}
+	else
+	{
+		WingUtils::CheckOpenEditorForAsset(OriginalAsset.Get(), nullptr);
+	}
+
 	return *this;
 }
 

Plugins/UEWingman/Source/UEWingman/Private/WingUtils.cpp

@@ -490,6 +490,30 @@ UObject *WingUtils::GetGeneratedCDO(UBlueprint *BP)
 	return BP->GeneratedClass->GetDefaultObject();
 }
 
+// ============================================================
+// Editor helpers
+// ============================================================
+
+IAssetEditorInstance* WingUtils::CheckOpenEditorForAsset(UObject* Asset, WingOut Errors)
+{
+	const FString AssetPath = Asset ? Asset->GetPathName() : TEXT("null");
+	UAssetEditorSubsystem* Sub = GEditor ? GEditor->GetEditorSubsystem<UAssetEditorSubsystem>() : nullptr;
+	if (!Sub || !Sub->OpenEditorForAsset(Asset))
+	{
+		Errors.Printf(TEXT("ERROR: Could not open editor for '%s'\n"), *AssetPath);
+		return nullptr;
+	}
+
+	IAssetEditorInstance* Editor = Sub->FindEditorForAsset(Asset, false);
+	if (!Editor)
+	{
+		Errors.Printf(TEXT("ERROR: Could not find editor instance for '%s'\n"), *AssetPath);
+		return nullptr;
+	}
+
+	return Editor;
+}
+
 // ============================================================
 // Material helpers
 // ============================================================

Plugins/UEWingman/Source/UEWingman/Public/WingFetcher.h

@@ -96,18 +96,6 @@ public:
 		return ::Cast<T>(OriginalAsset.Get());
 	}
 
-	// When an asset is loaded, an editor is automatically
-	// opened.  Get the editor.  You must specify the type
-	// that you expect the asset to be, and the type to cast
-	// the editor to.  Does not generate errors.
-	//
-	template<class AssetType, class EditorType>
-	EditorType* CastEditor()
-	{
-		if (!CheckAssetIsA(AssetType::StaticClass())) return nullptr;
-		return static_cast<EditorType*>(Editor);
-	}
-
 	// Calling SkipNotify disables change notifications
 	// for objects visited by this fetcher.  Useful for
 	// read-only operations that don't modify anything.
@@ -131,9 +119,8 @@ private:
 	TStrongObjectPtr<UObject> Obj;
 	UEdGraphPin* ResultPin = nullptr;
 
-	// The Starting Asset and the Editor we Opened.
+	// The Starting Asset.
 	TStrongObjectPtr<UObject> OriginalAsset;
-	IAssetEditorInstance* Editor = nullptr;
 
 	// True if an error has occurred.
 	bool bError = false;

Plugins/UEWingman/Source/UEWingman/Public/WingUtils.h

@@ -24,6 +24,7 @@ class UAnimStateTransitionNode;
 class IPropertyHandle;
 class UScriptStruct;
 class UEnum;
+class IAssetEditorInstance;
 struct FBPInterfaceDescription;
 struct FWingProperty;
 class IPropertyHandle;
@@ -247,6 +248,9 @@ public:
 	static TArray<UBlueprint*> GetAncestorBlueprints(UBlueprint *BP, bool OldestFirst = false);
 	static UObject *GetGeneratedCDO(UBlueprint *BP);
 
+	// ----- Editor helpers -----
+	static IAssetEditorInstance* CheckOpenEditorForAsset(UObject* Asset, WingOut Errors);
+	
 	// ----- Material helpers -----
 	static void EnsureMaterialGraph(UMaterial* Material);
 
@@ -277,4 +281,3 @@ public:
 	static bool CheckCanRename(UEdGraphNode* Node, const FString &Name, WingOut Errors);
 	static bool CheckNewObjectNotNull(UObject *Obj, const TCHAR *Kind, WingOut Errors);
 };
-