Unit-Testing delegating methods

Is there any point in Unit-Testing a method that the only thing it does is delegate work on another object? Example:

class abc {

    ...

    public void MoveLeft()
    {
        fallingPiece.MoveLeft();
    }

    ...
}

I am doing Unit-Tests for some existing classes I have, for learning purposes. It seems kinda odd to do a Unit-Test for this MoveLeft() method, for example. But I am unsure how would it have been had I开发者_如何学编程 done Test-First.

Thanks

Will your code break if I do this ? If it would, then you need a test to catch it.

class abc {
    ...
    public void MoveLeft()
    {
        // fallingPiece.MoveLeft();
    }
    ...
}

Assumptions: abc is a public / exposed type and fallingPiece is a dependency. If this holds, then you need a test to test the MoveLeft behavior. If it isn't a public type, then you need a test for the public type XYZ that uses abc as a colloborator/dependency. You don't directly test it but it still needs to be tested.

My understanding of unit tests is that they are there to ensure that the logic inside a method stays the same when you didn't intend for it to change, and this method has no logic in it. We have a lot of pass-through methods like that in the code base where I work. Ostensibly, they're "Controller" classes, but in most cases all they do is pass through to the data layer.

Yes, you can unit test them, assuming you have a way to mock fallingPiece. If you actually plan on expanding the MoveLeft method to include logic, it's probably a good idea.

However, to my comment above, it's probably a better move to just inline the method until you actually need to introduce logic around moving left.

One case that this method can fail is when fallingPiece is null when Abc.MoveLeft gets called. Having a test case that builds a legitimate abc and calls abc.MoveLeft might be good idea. something like CanMoveLeft() { Abc abc =new Abc(); abc.MoveLeft(); Assert.That( abc.fallingPice has moved to left) }