Wrap class

wrap-class.md

Wrap class.

How to do it:

1. Identify the change point.

2. Create a class that accepts the class we are going to wrap as a constructor argument.

   • If we have trouble creating the original class in a test harness, we might have to use Extract Interface on the wrapped class so that we can instantiate the wrapper.

3. Create a method on the wrapper class with tests, that implements the new behaviour.

   • The old behaviour will be called from the wrapper class.

4. Instantiate the wrapper class in your code in the place where you need to enable the new behavior.