title: How do I make pytest crash on a warning?
body: <p>this is an expansion of <a href="https://stackoverflow.com/questions/54486927/how-do-i-find-where-a-sorting-because-non-concatenation-warning-is-coming-from?noredirect=1#comment95781254_54486927">How do I find where a &quot;Sorting because non-concatenation&quot; warning is coming from?</a>. </p>
  
  <p>I'm still getting the same warning, in my pytest. I've looked at several questions here, and done:</p>
  
  <pre><code>import warnings
  warnings.filterwarnings('error')
  </code></pre>
  
  <p>which is suggested in <a href="https://stackoverflow.com/questions/15933741/how-do-i-catch-a-numpy-warning-like-its-an-exception-not-just-for-testing/15934081#15934081">How do I catch a numpy warning like it&#39;s an exception (not just for testing)?</a></p>
  
  <p>However, when I run pytest, it still gives me the error, but nothing actually errors... </p>