Automated integration or performance testing

We can use the unittest package to perform testing that isn't focused on a single, isolated class definition. As noted previously, we can use the unittest automation to test a unit that is an integration of multiple components. This kind of testing can only be performed on software that has passed unit tests on isolated components. There's no point in trying to debug a failed integration test when a component's unit test didn't work correctly.

Performance testing can be done at several levels of integration. For a large application, performance testing with the entire build may not be completely helpful. One traditional view is that a program spends 90 percent of its time executing just 10 percent of the available code. Therefore, we don't often need to optimize an entire application; we only need to locate the small fraction of the program that represents the real performance bottleneck.

In some cases, it's clear that we have a data structure that...