macOS 10.12 auto-layout issues
<p>There are several huge changes in 10.12, but in my opinion the biggest is the new auto-layout system (or modified/rewritten old one ... who knows). I have prepared a simple project to demonstrate the issue. It's related with collapsing a split view item via a button. It happens only on 10.12. All you need to do is to compile the project and click the button. An error will be presented:</p>

<blockquote>
  <p>2016-10-04 15:10:28.284296 test-12[64932:7425277] [Layout] Detected missing constraints for .  It cannot be placed because there are not enough constraints to fully define the size and origin. Add the missing constraints, or set translatesAutoresizingMaskIntoConstraints=YES and constraints will be generated for you. If this view is laid out manually on macOS 10.12 and later, you may choose to not call [super layout] from your override. Set a breakpoint on DETECTED_MISSING_CONSTRAINTS to debug. This error will only be logged once.</p>
</blockquote>

<p>After setting a breakpoint we can find out that the problematic view is:</p>

<pre><code>(lldb) po $arg1
&lt;NSSplitDividerView: 0x618000161980&gt;
</code></pre>

<p>Am I completely wrong or there is a definite problem with 10.12? And please advice how to prevent such type of errors if possible. </p>

<p>The project can be downloaded from <a href="https://github.com/ivailon/test-12">github</a></p>

<p>Once again thank you for the help.</p>

<p>I. Nikolov</p>