title: Rails: Calling URL helpers with string keys controller, action is deprecated. Use symbols instead?
body: <p>Im getting a: </p>
  
  <blockquote>
    <p>"DEPRECATION WARNING: Calling URL helpers with string keys controller,
    action is deprecated. Use symbols instead"</p>
  </blockquote>
  
  <p>When running unit tests, I looked around at this and while im new to rails I haven't exactly nailed down a ton of examples of this. It seems to come from the params symbols usually but a lot of the google results are complaining that this is an erroneous warning?</p>
  
  <p>In my case it's complaining about this particular line:</p>
  
  <pre><code>&lt;%= link_to exports_path(params.merge(format: 'xlsx')), :class =&gt; "btn btn-primary btn-xls" do %&gt;&lt;i class="glyphicon glyphicon-download"&gt;&lt;/i&gt;Export XLXS&lt;/a&gt; &amp;nbsp; &lt;% end %&gt;
  </code></pre>
  
  <p>Im assuming it's complaining about the <code>params.merge(format: 'xlsx'))</code> but I don't understand why? Usually i've seen this error when symbols are used but there are no symbols being used here.</p>