Comparing the MSTest and Nunit Frameworks

  • Article

I haven't seen much information online comparing the similarities and differences between the Nunit and MSTest Frameworks. Here I will define the similarities and some of the differences. If there is anything else which you come upon, please do add it to the comments.

MSTest Attribute

NUnit Attribute

Purpose

[TestMethod]

[Test]

Indentifies of an individual unit test

[TestClass]

[TestFixture]

Identifies of a group of unit tests, all Tests, and Initializations/Clean Ups must appear after this declaration

[ClassInitialize]

[TestFixtureSetUp]

Identifies a method which should be called a single time prior to executing any test in the Test Class/Test Fixture

[ClassCleanup]

[TestFixtureTearDown]

Identifies a method in to be called a single time following the execution of the last test in a TestClass/TestFixture

[TestInitialize]

[SetUp]

Identifies a method to be executed each time before a TestMethod/Test is executed

[TestCleanUp]

[TearDown]

Identifies a method to be executed each time after a TestMethod/Test has executed

[AssemblyInitialize]

 N/A

Identifies a method to be called a single time upon before running any tests in a Test Assembly

[AssemblyCleanUp]

 N/A

Identifies a method to be called a single time upon after running all tests in a Test Assembly

 The order of execution is similar in both frameworks, but there are some differences between the two:

  • In Nunit, tests are not executed in parallel. Rather, it appears that all tests execute on a single thread. In MSTest, each test is instantiated on a separate thread, this results the runs being interleaved. Therefore, if test A depends on test B for its success, it likely will fail as test B will likely start running as test A is running.
  • The time at which ClassCleanUp/TestFixtureTearDown executes is different between the two frameworks. In Nunit, TestFixtureTearDown is executed immediately following the completion of the last test in a TestFixture or after TearDown if the attribute exists for the test in question. In the Whidbey implementation of MsTest, ClassCleanUp executes at the end of a test run, before AssemblyCleanUp but not necessarily immediately after the last test in a TestClass has completed executing.
  • In Whidbey, support for test class inheritance was missing. In Nunit, it is fully supported. This will be rectified in Orcas.

I should also mentioned that in MsTest, TestContext exists for passing information about the test run. There is no equivalent in Nunit tests. This can serve as a handy tool for pulling information from datasources on the disk to the unit tests, as well as other uses. More can be read about it here.

Comments

  • Anonymous
    March 27, 2007
    Are there plans to add support for NUnit's Category attribute? http://nunit.org/index.php?p=category&r=2.4 Buck

  • Anonymous
    March 27, 2007
    Naysawn Naderi has a matrix of attributes between NUnit and MSTest . To balance MbUnit in this matrix,

  • Anonymous
    April 01, 2007
    I just came across a great blog entry that compares the different attributes in both MSTest and NUnit.

  • Anonymous
    April 01, 2007
    The comment has been removed

  • Anonymous
    April 04, 2007
    From Buck: "Are there plans to add support for NUnit's Category attribute?" We have been discussing this.  I think that it would be quite beneficial.  Do you prefer it to the test lists that we have implemented?

  • Anonymous
    May 11, 2007
    The comment has been removed

  • Anonymous
    May 11, 2007
    Now, I'm not claiming to be anything remotely close to a Test-Driven Development expert - heck, I only

  • Anonymous
    July 28, 2007
    I think that [AssemblyInitialize] and [AssemblyCleanUp] in MSTest correspond to [SetUp] and [TearDown] in the [SetUpFixture] of NUnit.

  • Anonymous
    September 18, 2007
    The comment has been removed

  • Anonymous
    September 18, 2007
    The comment has been removed

  • Anonymous
    October 29, 2007
    MBUnit's TestSuiteFixture is a TestClass than can be populated at runtime (e.g. by fetching data from files in folders). Only way I know of doing that with MSTest is by adding an MSBuild task that runs before project compilation, that generates source code (i.e. alla CodeSmith), that will later be compiled by CSC and finally detected as a test by MSTest.

  • Anonymous
    December 17, 2009
    Some major differences in MSTest compared to NUnit is that:

  1. Inheritance is not supported if the base class is in different assembly
  2. ClassInitialize and ClassCleanup attribute methods MUST be static which enforces a lot of restriction in actually using those attributes

  • Anonymous
    August 28, 2010
    Hi. I'm wondering about why support for inheritance of test classes is still not supported?? I wrote a question about it on stackoverflow.com, perhaps somebody reads this and can answer it: stackoverflow.com/.../is-defining-testmethods-in-test-base-classes-not-supported-by-mstest Thanks

  • Anonymous
    August 11, 2011
    This might help: Unit testing frameworks: MSTest v/s NUnit @ http://santats.blogspot.com/

  • Anonymous
    January 21, 2013
    thanks,Actually [TestCleanUp] should be [TestCleanup] and [AssemblyCleanUp] should be [AssemblyCleanup].

  • Anonymous
    July 30, 2013
    Why One Sided review? MSTest still don't have "TestCase" attribute which NUnit has, it makes calling the same test method several times with different parameters, very easy.