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VB -> C#: CType(Nothing, <Nullable>?) returns default instead of null

See original GitHub issue

VB.Net input code

Imports System

Public Class VisualBasicClass
    Dim SomeDate As String = "2022-01-01"
    Dim SomeDateDateParsed As Date? = If(String.IsNullOrEmpty(SomeDate), CType(Nothing, Date?), DateTime.Parse(SomeDate))
    Dim SomeDateDateNothing As Date? = If(String.IsNullOrEmpty(SomeDate), Nothing, DateTime.Parse(SomeDate))
End Class

Erroneous output

using System;

public partial class VisualBasicClass
{
    private string SomeDate = "2022-01-01";
    private DateTime? SomeDateDateParsed;
    private DateTime? SomeDateDateNothing;

    public VisualBasicClass()
    {
        SomeDateDateParsed = string.IsNullOrEmpty(SomeDate) ? default : DateTime.Parse(SomeDate);
        SomeDateDateNothing = string.IsNullOrEmpty(SomeDate) ? default : DateTime.Parse(SomeDate);
    }
}

Expected output

using System;

public partial class VisualBasicClass
{
    private string SomeDate = "2022-01-01";
    private DateTime? SomeDateDateParsed;
    private DateTime? SomeDateDateNothing;

    public VisualBasicClass()
    {
        SomeDateDateParsed = string.IsNullOrEmpty(SomeDate) ? null: DateTime.Parse(SomeDate);
        SomeDateDateNothing = string.IsNullOrEmpty(SomeDate) ? default : DateTime.Parse(SomeDate);
    }
}

Details

Product in use: both
Version in use: e.g. 9.1.3.577
Did you see it working in a previous version, which? No
Any other relevant information to the issue, or your interest in contributing a fix. I know it’s tricky in VB with Nothing, but I think in this scenario it should be null, not default. Please check the fiddle: https://dotnetfiddle.net/PwEL1D