title: How to group an array of objects by name and sum
body: <p>For example:</p>
  <pre><code>        [Test(count: 5, name: &quot;Ivan&quot;, innerNumber: &quot;123123&quot;),
           Test(count: 5, name: &quot;Ivan&quot;, innerNumber: &quot;123123&quot;),
           Test(count: 10, name: &quot;Miko&quot;, innerNumber: &quot;4312432&quot;),
           Test(count: 10, name: &quot;Miko&quot;, innerNumber: &quot;4312432&quot;)]
  </code></pre>
  <p>I want to group an array by <code>name</code> field and sum by <code>count</code> field</p>
  <p>As a result, I want an array in the form:</p>
  <pre><code>        [Test(count: 10, name: &quot;Ivan&quot;, innerNumber: &quot;123123&quot;),
           Test(count: 20, name: &quot;Miko&quot;, innerNumber: &quot;4312432&quot;)]
  </code></pre>