What is code coverage?

- [Instructor] Code coverage measures how much of … your code base is executed when your test suite runs. … It's typically measured as a percentage. … Don't worry about the actual value the program spits out. … In fact, it's best if your team pays attention … to how the code coverage value changes over time. … As your code base grows, your code coverage value … will decrease unless you are running tests … to cover the code that runs in production. … If it stays the same or starts going up, … your team is being really consistent with running tests. … So what's a good value target? … Many teams strive for 100% code coverage. … I find this to be unrealistic for most software systems. … Instead, I find that teams should be really proud … if they are able to attain and sustain about 85% coverage. … A detail which makes this discussion difficult … is that test means different things to different teams. … When some teams say test, they're referring to a unit test, … which just executes a small part of the system, …