AUT - Application Under Test

Given the following module with two functions, how can we verify that these functions work properly.

The mymath.py file contains the following:

def add(x, y):
    return x * y

def multiply(x, y):
    return x + y

# Yes, I know there are bugs in this code!

You probably noticed that the operators in our functions are incorrect. The function called add is expected to add two numbers, but the implementation has a bug. It actually multiplies the two numbers. The function called multiply on the other hand actuall adds the operands together.

I know it is a very obvious issue, but it is great as it allows us to see the mechanics of testing without getting distracted by a complex implementation and a complex problem.

Rest assured, the mechanism of the testing would be the same even if our function was calculating the moon-landing trajectory.

Testing is not rocket science.