[Bug]: Mock a class with its constructor calling a mocked method result in Null MockEngine exception

[elTRexx]

Description

When mocking a class which have its constructor calling a method that itself is also mocked (being virtual / abstract), cause the MockEngine _engine field in the generated mock implementation not being set in time when already calling the base() constructor that in turn call the mocked method :

Expected Behavior

The MockEngine _engine field should be set before calling base() constructor

Actual Behavior

The base() constructor is called before MockEngine _engine field have been set.

Steps to Reproduce

public class MyClass
{
  public MyClass() 
  {
    A();
  }

  public virtual void A()
  { }
}

[Test]
public async Task MyTest()
{
  var mock = MyClass.Mock();

  mock.Object.A();

  await Assert.That(mock.A).WasCalled();
}

See in debugging steps that in source generated file sealed class StateTests_MyClassMockImpl file
its constructor

1. call the base() constructor
2. MyClass constructor call A()
3. mocked StateTests_MyClassMockImpl.A() method is then called
4. NullReferenceException is thrown on _engine field

TUnit Version

1.65.68

.NET Version

.Net 9.0 C#14 preview

Operating System

Windows

IDE / Test Runner

Visual Studio

Error Output / Stack Trace

[Null Reference] Object reference not set to an instance of an object.

Additional Context

No response

IDE-Specific Issue?

• I've confirmed this issue occurs when running via dotnet test or dotnet run, not just in my IDE