Unreal Engine Issues and Bug Tracker (UE-76380)

Description

Certain Map container calls (e.g. Find, Add) will fail to compile at packaging time if a Blueprint class containing a Map variable with a user-defined enumeration as the key type is nativized.

This is similar to the issue described in [Link Removed].

Suggested workaround: Change the key type from the UserDefinedEnum type to Byte, then fix up connections to existing Map container call nodes.

Steps to Reproduce

Create a new (blank) Blueprint-only project.
Create a new User-Defined Enumeration and add at least one entry. Save.
Create a new Actor-based Blueprint class, double-click to open in the Blueprint editor.
Add a new variable and change its container type to 'Map' with a key type of the User-Defined enumeration created above. The value type can remain as integer (default).
Click over to the Event Graph tab and drag the map variable into the graph. Choose to create a "Get" node.
Drag off the "Get" node and choose the "Find" function. Drag off the Key input pin and choose "Make a Literal NewUserDefinedEnum." Leave the default value as-is.
Drag off the "Find" node's output pin and connect it to a PrintString node.
Connect the PrintString node to the BeginPlay event.
Compile and save the Blueprint class.
In the project settings, change the Blueprint nativization method to "Inclusive."
Choose File->Package Project->Windows->Win64 and wait for packaging to finish. An error will result:

UATHelper: Packaging (Windows (64-bit)):     D:\dev\UE4\Dev-Framework\Engine\Source\Runtime\Engine\Public\GeneratedCodeHelpers.h(427): error C2663: 'TMapBase<KeyType,ValueType,SetAllocator,KeyFuncs>::Find': 2 overloads have no legal conversion for 'this' pointer
UATHelper: Packaging (Windows (64-bit)):             with
UATHelper: Packaging (Windows (64-bit)):             [
UATHelper: Packaging (Windows (64-bit)):                 KeyType=E__NewUserDefinedEnum__pf,
UATHelper: Packaging (Windows (64-bit)):                 ValueType=int32,
UATHelper: Packaging (Windows (64-bit)):                 SetAllocator=FDefaultSetAllocator,
UATHelper: Packaging (Windows (64-bit)):                 KeyFuncs=TDefaultMapHashableKeyFuncs<E__NewUserDefinedEnum__pf,int32,false>
UATHelper: Packaging (Windows (64-bit)):             ]
UATHelper: Packaging (Windows (64-bit)):     D:/dev/local/Projects/NatMapEnumKeyTest/Intermediate/Plugins/NativizedAssets/Windows/Game/Source/NativizedAssets/Private/NewBlueprint__pf1010915279.cpp(472): note: see reference to function template instantiation 'bool FCustomThunkTemplates::Map_Find<E__NewUserDefinedEnum__pf,int32,uint8,int32>(const TMap<E__NewUs
erDefinedEnum__pf,int32,FDefaultSetAllocator,TDefaultMapHashableKeyFuncs<KeyType,ValueType,false>> &,const V &,W &)' being compiled
UATHelper: Packaging (Windows (64-bit)):             with
UATHelper: Packaging (Windows (64-bit)):             [
UATHelper: Packaging (Windows (64-bit)):                 KeyType=E__NewUserDefinedEnum__pf,
UATHelper: Packaging (Windows (64-bit)):                 ValueType=int32,
UATHelper: Packaging (Windows (64-bit)):                 V=uint8,
UATHelper: Packaging (Windows (64-bit)):                 W=int32
UATHelper: Packaging (Windows (64-bit)):             ]

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Fixed

Component	UE - Gameplay - Blueprint
Affects Versions	4.20, 4.21, 4.22, 4.23
Target Fix	4.26

Fix Commit	14219534
Main Commit	14219534

Created	Jun 17, 2019
Resolved	Aug 31, 2020
Updated	Apr 28, 2021

UE-76380

Error during packaging if nativizing a blueprint that contains a TMap with a UserDefinedEnum as a key

Error during packaging if nativizing a blueprint that contains a TMap with a UserDefinedEnum as a key

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