ExpectGet (in Mock class) equivalent in AAA API

Getting the hang of AAA API is very easy - it replaces the old record/replay model, and allows you to set and verify your expectations easily. I suggest you read our "Getting Started with AAA API" to learn how to use it.

As to your question, suppose you have a class with a get property, like:

public class Person
{
    private string person;

    public string Name { get { return person; } }
}

In order to have the property return a value you want, simply use "WhenCalled" and "WillReturn":

Person person = ...
Isolate.WhenCalled(() => person.Name).WillReturn("David");

...
Assert.AreEqual("David", person.Name);