title: XCTestAssertNil crash due to "nil" parameter
body: <p>I'm using XCTest to write unit tests in my project, and when using the <code>XCAssertNil()</code> or <code>XCAssertNotNil()</code> methods, XCTest framework crashes.</p>
  
  <p>Here's my test:</p>
  
  <pre><code>XCTAssertNotNil(messageCollection.fieldName, "field_name must be not-nil")
  </code></pre>
  
  <p>Here's the stack trace:</p>
  
  <pre><code>2015-06-22 17:05:17.629 xctest[745:8747] *** Assertion failure in void _XCTFailureHandler(XCTestCase *, BOOL, const char *, NSUInteger, NSString *, NSString *, ...)(), /SourceCache/XCTest_Sim/XCTest-7701/XCTestFramework/OtherSources/XCTestAssertionsImpl.m:41
  Test Case '-[Wakanda_iOS_Framework_Tests.WAKAdapterTest testEntityCollectionParsing]' started.
  2015-06-22 17:05:17.631 xctest[745:8747] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Parameter "test" must not be nil.'
  </code></pre>
  
  <p><strong>It seems that XCTest has a parameter named <em>test</em> which cannot be nil</strong>, strange for a method expected to check for nil (or non-nil) values... Does anyone else got this problem and solved it?</p>