Using Microsoft Fakes with factory instance methods

Question

I got a class that looks like this:

public class MyClass
{
    int myNum;

    private MyClass() {}

    public static MyClass CreateInstance()
    {
        MyClass a = new MyClass();
        a.myNum=5;
        return a;
    }

    public bool IsBigger(MyClass b)
    {
        return this.myNum > b.myNum;
    }

}

then, i want to make a shim of it and want to use the IsBigger method, but by default it returns false. How do i call the base method in this instance case ?

The test goes like this:

[TestMethod]
Public void test()
{
 ShimMyClass firstShim = new ShimMyClass();
 firstShim.myNumGet = () => { return 6; }

 ShimMyClass secondShim = new ShimMyClass();
 secondShim.myNumGet = () => { return 7; }

 Assert.IsTrue(secondShim.Instance.IsBiggerThan(firstShim.Instance);
}

Show how you call the IsBigger-method. And what do you mean with base-method? There is no base-method in my opinion... — Abbas, Oct 09 '12 at 12:36
I meN than with unit test i create a shim instance and set the myNum to other numbers. Than i call firstShimMyClass.Instance.IsBiggerThan(otherShimClass), but it returns falls even if i didnt implemented it — Lironess, Oct 09 '12 at 12:39

oberfreak · Answer 1 · 2012-10-10T07:45:19.797

0

Make MyNum a Property:

public class MyClass
{
    public int MyNum { get; private set; }

    private MyClass() {}

    public static MyClass CreateInstance()
    {
        MyClass a = new MyClass();
        a.MyNum=5;
        return a;
    }

    public bool IsBigger(MyClass b)
    {
        return this.MyNum > b.MyNum;
    }

}

Create Shim Context before using the ShimMyClass:

using (ShimsContext.Create())
{ 
    ShimMyClass firstShim = new ShimMyClass();
     firstShim.MyNumGet = () => { return 6; }

     ShimMyClass secondShim = new ShimMyClass();
     secondShim.MyNumGet = () => { return 7; }

     Assert.IsTrue(secondShim.IsBiggerThan(firstShim);
}

Microsoft Fakes on MSDN

edited Oct 10 '12 at 07:45

answered Oct 09 '12 at 12:35

oberfreak

1,799
13
20

From outside. Lets say that i can change it. Its just an example class. – Lironess Oct 09 '12 at 12:37
have you tried debugging it? Because i don't see a problem in your sample class! How do you set it from outside? In the sample it is private – oberfreak Oct 09 '12 at 12:42
i didn't tried it but i think you can remove the "Instance" property access. Maybe it will work then? – oberfreak Oct 10 '12 at 07:46
What is your result from debugging? Are there any exceptions? – oberfreak Oct 11 '12 at 07:42

Using Microsoft Fakes with factory instance methods

1 Answers1