Question

How do you verify the number of elements in a set in Easymock? The class I’m testing should call a method, passing in a set with n elements. Right now, I’m matching any object for the list:

    mockFooSetReceiver.saveFooSet(eq(name), 
            (List<IFooSet>) anyObject());
    replay(mockFooSetReceiver);

What I’d like to specify the number of elements in the set:

    mockFooSetReceiver.saveFooSet(eq(name), 
            setOfNObject(100));
    replay(mockFooSetReceiver);

Or better yet, match the elements in the set:

    mockFooSetReceiver.saveFooSet(eq(name), 
            setEq(ecpectedSet));
    replay(mockFooSetReceiver);

Do I have to roll my own matcher, of is there one built in? Or does someone have a setOfNObject or setEq matcher that they’d like to share?

Answer 1

As Sets must implement equals(..) according to this contract:

Compares the specified object with this set for equality. Returns
true if the specified object is also a set, the two sets
have the same size, and every member of the specified set is
contained in this set (or equivalently, every member of this set is
contained in the specified set). This definition ensures that the
equals method works properly across different implementations of the
set interface.

a simple EasyMock.eq(ecpectedSet) does the job.

If it’s only the size of the set @Guillaume’s answer is the way to go.