Whew! We gave you a lot to chew on in this chapter, from broad advice on test doubles to fine-grained design nuances. Here are just some of the principles we explored over several code examples:
That’s a lot to keep in your head, but we’re definitely not asking you to do that! All of these bits of advice stem from one key practice: constructing your test environment carefully. Remember the laboratory metaphor when you’re writing your specs, and you should be fine.