http://ayende.comAyende @ RahienCopyright (C) Ayende Rahien 2004 - 2021 (c) 202660>> That's nothing compared to my bug of the day: >> try running this piece of code in the immediate window and then in the body of a funcion. >> bool a = object.ReferenceEquals("A","A") a would be true as the compiler would have inturned the string "A" http://ayende.com/3395/bug-of-the-day#comment8http://ayende.com/3395/bug-of-the-day#comment8Thu, 03 Jul 2008 10:37:15 GMTThat's nothing compared to my bug of the day: try running this piece of code in the immediate window and then in the body of a funcion. bool a = object.ReferenceEquals("A","A") http://ayende.com/3395/bug-of-the-day#comment7http://ayende.com/3395/bug-of-the-day#comment7Wed, 02 Jul 2008 14:28:02 GMTThat's because GUIDs are so unique that even two identical GUIDs are not quite equal. Duh. http://ayende.com/3395/bug-of-the-day#comment6http://ayende.com/3395/bug-of-the-day#comment6Wed, 02 Jul 2008 09:19:13 GMTMaybe it been updated since the version I'm running (1.0.2700) but the real problem I see is that AreEqual(object, object) uses the object's Equals() methods (via ObjectsEqual) which is customized to the class, while AreNotEqual just uses !(obj==obj) which ultimately just Object.ReferenceEquals. http://ayende.com/3395/bug-of-the-day#comment5http://ayende.com/3395/bug-of-the-day#comment5Wed, 02 Jul 2008 00:46:02 GMTThanks Oren, I'll need to investigate this more but I think in the absence of an assert for Guid that MbUnit is casting to object and then equating as a null. The AreNotEqual has this gem. if (expected == null ^ actual == null) return; As both become null in the cast it passes. Thats a complete guess at the moment until I can investigate more. Always fun. Andy http://ayende.com/3395/bug-of-the-day#comment4http://ayende.com/3395/bug-of-the-day#comment4Tue, 01 Jul 2008 22:02:47 GMTIt's funny that I have stumbled in the exactly same bug today. Well, seems almost no one is actually using AreNotEqual if this lived to the 2.4. http://ayende.com/3395/bug-of-the-day#comment3http://ayende.com/3395/bug-of-the-day#comment3Tue, 01 Jul 2008 22:01:49 GMTYep, ran into that one a while ago... http://code.google.com/p/mb-unit/issues/detail?id=114 http://ayende.com/3395/bug-of-the-day#comment2http://ayende.com/3395/bug-of-the-day#comment2Tue, 01 Jul 2008 22:00:14 GMTwell that's helpful http://ayende.com/3395/bug-of-the-day#comment1http://ayende.com/3395/bug-of-the-day#comment1Tue, 01 Jul 2008 21:02:53 GMT