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[Adam Brengesjö <ca.brengesjo@xxxxxxxxx>]

I agree. Breaking changes is a *major* concern.

>Besides that I'm not sure it would be sensible to compare
>DateTimes using a logic different from that of the default .NET
>implementation, it might be confusing for users.

Initially that was my thought too.
But NUnit does other comparisons different from .NET, like when comparing arrays.
.NET will simply evaluate them as different, while NUnit compares each element (which I really love and is one of the features that kicks MSTest's butt....)


I can see your point. And I wish I could provide a more obvious case. I'm just hoping other could benefit from this.

I discovered this after tracking down a bug where (I later concluded)
* a handheld device re-constructed datetimes from the database without setting Kind
* which lead to the communication layer omitting the time offset...
* which caused the server to parse the time as local...
* which led to a incorrect utc time being written to the database...
* which caused the web to supply the browser with a incorrect time...
* which had the web javascript add incorrect time offset when displaying the timestamp...

After I changed well over 2000 DateTime assertions in the test suite,
about 5% of them failed because the the Kind property was not set or not
what was expected.

Of course, this was not caused by NUnit, but as a framework, NUnit should help sloppy (or unknowing) developers from making common, but not so obvious, mistakes.
And this is a rather... unintuitive feature of .NET... which I belive is a case where NUnit could prove very helpful to developers (which NUnit already is btw in so many other cases).

-- 
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Developers, which is subscribed to NUnit V2.
https://bugs.launchpad.net/bugs/1172247

Title:
  Improve DateTime equality assertions to include DateTimeKind

Status in NUnit V2 Test Framework:
  New

Bug description:
  The following test will fail, even if the two DateTime structs are not equal.
  (I know it's because the equality members of the DateTime type does the evaluation which doesn't care of the Kind property)

  [Test]
  public void Foo()
  {
      var localDate = new DateTime(2013, 04, 24, 13, 17, 44, 678, DateTimeKind.Local);
      var systemDate = new DateTime(2013, 04, 24, 13, 17, 44, 678, DateTimeKind.Utc);

      Assert.AreNotEqual(localDate, systemDate);
  }

  But I always extracts my assertions to a helper method which also
  checks the Kind property.

  public static class AssertX
  {
      public static void AreEqual(DateTime expected, DateTime actual)
      {
          Assert.AreEqual(expected, actual);
          Assert.AreEqual(expected.Kind, actual.Kind);
      }
  }

  I would like to have NUnit help me with this instead of always calling
  my own helper class.

  However, I'm not sure how this best could be implemented in NUnit.
  A simple overload of AreEqual(object, object) to AreEqual(DateTime, DateTime) risk breaking compability with existing tests out there.

  One way would be to instead use another name, Assert.Identical or
  similar.

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