title: Integration and Unit tests
body: <p>In the last days I studied about tests with Jest, but i don't understood the next.
  When I have integration tests I don't use mock? Mock are used just on unit tests?</p>
  <p><strong>UPDATE</strong>
  Today, in my company, the approach that we follow is: Unit tests always mock all external access data, and integration tests should not mock.</p>
  <p>Is interesting, associate integration tests with hlg environment, because you can discovery easily what and where broke software</p>