Unit testing
As we explained in the previous section, as part of unit testing, we test isolated units and a unit can be as small as a function or as big as a component. In C, it can be a function or a whole component written in C. The same discussion can be applied to C++ as well, but there we can have other units like classes.
The most important thing about unit testing is that units should be tested in isolation. For example, if the target function depends on the output of another function, we need to find a way to test the target function in isolation. We are going to explain this using a real example.
Example 22.1 prints the factorials of even numbers less than 10, but not in the usual way. The code is well-organized in one header and two source files. The example is about two functions; one of them generates the even numbers less than 10 and the other function receives a function pointer and uses it as a source for reading an integer number, and finally calculates...
