Python: self.assertEqual(a, b, msg) --> I want diff AND msg
<p>If I call it like this, I see a nice diff:</p>

<pre><code>self.assertEqual(a, b)
</code></pre>

<p>If I call it like this, I see the msg only:</p>

<pre><code>self.assertEqual(a, b, msg)
</code></pre>

<p>Is there an easy way to show the diff AND the msg?</p>

<p>Implementing <code>assertEqual()</code> myself would work, but I ask myself if this is really the best way.</p>

<p>Plattform: Python2.7 and pytest 2.6.2.</p>