Parsing ESPMode::ThreadSafe as Template Argument in Version 18.0.1

[Liangjia0411]

I am encountering an issue while parsing code with ESPMode::ThreadSafe as a template argument using version 18.0.1. The problematic code snippet is as follows:

struct MONOSAMPLE_API FAuto_ExportProperty
{
    TSharedPtr<FKey, ESPMode::ThreadSafe> a;
};

In this code, ESPMode is an enumeration and ESPMode::ThreadSafe is used as a template argument for TSharedPtr. However, when I parse this code with version 18.0.1, ESPMode::ThreadSafe is incorrectly interpreted as a parameter pack, leading to subsequent parsing errors.

This issue does not occur when I parse the same code with version 16.0.0.

Could you please look into the differences between these two versions? I suspect this might be a bug in the new version.

This code is written based on the UE4.27 engine.