Visual Studio 2010 does not discover new unit tests

Question

I am writing some unit tests in Visual Studio 2010. I can run all tests by using "Run all Tests in Current Context".

However, if I write a new unit test, it does not get picked up by the environment - in other words, I am not able to find it in Test List Editor, by running all tests, or anywhere else. If I unload the project and then reload it; the new test is available to run.

When I am adding a unit test, I simply add a new method to an already existing TestClass and decorating it with [TestMethod] attribute - nothing fancy.

What might be causing this behaviour, and how do I make it work ?

What are the steps you are doing that is causing a problem? There are several ways to run tests, so it is hard to come up with a good answer. — James Black, Apr 25 '10 at 14:13
@James, I use either "Run tests in current context" or "Run all tests in solution" from the toolbar. Normal behavior of these is to include any new tests that I have added. — driis, Apr 26 '10 at 12:34

driis · Accepted Answer · 2014-10-18T13:47:56.227

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I finally figured out the problem. In Options under Test Tools -> Test Project, there is an option "Disable background discovery of test methods". It was turned on - I do not know how that happened, but removing the checkmark and restarting Visual Studio solved the problem.

edited Oct 18 '14 at 13:47

answered Apr 26 '10 at 12:40

driis

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Thank you! This is has been so frustrating since upgrading. Why in the world is discovery disabled by default? – sgwill Jun 12 '10 at 20:19
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Thank you, you saved lot of my time. – Signcodeindie Nov 11 '10 at 08:41
Question is, how come this check box suddently checked itself on? – Johnny5 Feb 29 '12 at 20:20
Awesome! This setting changed as I redid my solutions leaving the test project out of some build configurations. Could that be the cause for anyone else? – strongriley Aug 09 '12 at 01:13
I am sure this is late, but it is because of ReSharper. I had the same issue and your screenshot shows that you have ReSharper installed just like I do. – Issa Fram Sep 30 '13 at 19:16

score 3 · Answer 2 · answered Apr 23 '10 at 21:51

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I've had this problem as well when building in debug mode. When I switched it to build in release mode that fixed it for me.

answered Apr 23 '10 at 21:51

amurra

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score 2 · Answer 3 · edited Apr 09 '15 at 13:54

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I had a similar problem in Visual Studio 2012, however none of the solutions worked. I am developing a 64 bit application and the solution was to choose:-

Test -> Test Settings -> Default Processor Architecture -> X64

edited Apr 09 '15 at 13:54

HaveNoDisplayName

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answered Apr 09 '15 at 13:50

Cookie

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score 0 · Answer 4 · answered Jun 16 '14 at 13:04

I've had this issue and option 2 below fixed it for me.

Remove any app.config file (not sure why, but one of the MS forums has a few of these posts with this solution) and
Ensure that within the configuration properties of the solution the project is set to build!!

Visual Studio 2010 does not discover new unit tests

4 Answers4

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