High Cost Tests and High Value Tests

There is a value in writing tests and there is also a cost. The currency is time. The trade-offs are difficult to evaluate because the cost and value are often seen by different people. The writer of the test bears much of the short term cost while long term benefits and cost are borne by the rest of the team. By planning around both the the cost and value of your tests, you’ll improve your tests and your code. How much do slow tests cost? When is it worth it to test an edge case? How can you tell if testing is helping? Here are some strategies to improve your tests and code.