<p>Is it possible for <code>SelectNodes()</code> called on an <code>XmlDocument</code> to return null?</p>

<p>My predicament is that I am trying to reach 100% unit test code coverage; ReSharper tells me that I need to guard against a null return from the <code>SelectNodes()</code> method, but I can see no way that an XmlDocument can return null (and therefore, no way to test my guard clause and reach 100% unit test coverage!)</p>

Is it necessary to reach 100% code coverage? Indeed, is it even possible under normal (i.e. controllable, testable) circumstances?
We often find that using "syntactic sugar" constructions like the
```
using {}
```
block, there are "hidden" code paths created (most likely
```
finally {}
```
or
```
catch {}
```
blocks) that can't be exercised unless some environmental condition (like a broken socket or broken disk) gets in the way.