title: Sbt: when to use testQuick and how does it determine which tests to skip?
body: <p>According to sbt documentation, when running <code>testQuick</code>, it executes</p>
  
  <ul>
  <li>The tests that failed in the previous run</li>
  <li>The tests that were not run before</li>
  <li>The tests that have one or more transitive dependencies, maybe in a different project, recompiled. </li>
  </ul>
  
  <p>How does sbt determine which tests qualify? If it is based on cached results, where is this cache?</p>