Why is the Visual Studio 2015/2017/2019 Test Runner not discovering my xUnit v2 tests

Question

UPDATE: Adding a 2019; the discovery/runner integration mechanism is same as per 2017 & 2015, so the key things that can go wrong are the same.

I've read Why is the xUnit runner not finding my tests, which covers reasons xUnit would never be able to find your tests but my problem is different - I'm confident there's nothing subtle going on with my tests; (they have worked in other environments, this seems to be just my machine) - the Visual Studio Test Runner in Visual Studio 2015 [Community Edition] is simply not showing any of my tests. I'm not doing anything remotely exciting; the tests target xUnit.net v2 on the Desktop.

I've looked in the Output window and am not seeing anything in at all under Test in the Show output from tabs.

related: http://stackoverflow.com/questions/16214684/why-is-the-xunit-runner-not-finding-my-tests — Ruben Bartelink, Sep 30 '16 at 11:03
It is just *one* possible problem, but obviously you have to compile the test project before it will be shown in the test explorer. — Niklas Peter, Nov 09 '16 at 11:14
This worked for me - https://stackoverflow.com/questions/42861930/unit-tests-not-discovered-in-visual-studio-2017 — Prisoner ZERO, Jul 12 '18 at 16:08
Installing Xunit.Runner.VisualStudio has resolved my problem — Bendram, Jun 30 '20 at 13:17
I had this problem, by forgetting to make my new test class public. — Divan, Jun 12 '21 at 12:36

score 239 · Answer 1 · edited Jun 23 '22 at 08:53

239

Eliminate discovery exceptions from your inquiries; go to the output Window (Ctrl-Alt-O), then switch the show output from dropdown (Shift-Alt-S) to Tests and make sure there are no discovery exceptions
Test|Test settings|Default processor architecture can help if your tests are x86/x64 specific and discovery is triggering bittedness-related exceptions, i.e. not AnyCpu
As suggested in this answer(upvote it if the technique helps) running the desktop console runner (instructions) can be a good cross check to eliminate other possibilities, e.g. mangled config files:-

> packages\xunit.runner.console.2.2.0\tools\xunit.console <tests.dll>

NOTE The xunit.runner.console package is deprecated - when you get stuff working in VS, you'll be able to have dotnet test run them in CI contexts too

Go read the documentation - it's comprehensive, up to date, includes troubleshooting info and takes PRs:-

Important note: If you've previously installed the xUnit.net Visual Studio Runner VSIX (Extension), you must uninstall it first. The Visual Studio runner is only distributed via NuGet now. To remove it, to go Tools > Extensions and Updates. Scroll to the bottom of the list, and if xUnit.net is installed, uninstall it. This will force you to restart Visual Studio.

If you're having problems discovering or running tests, you may be a victim of a corrupted runner cache inside Visual Studio. To clear this cache, shut down all instances of Visual Studio, then delete the folder %TEMP%\VisualStudioTestExplorerExtensions. Also make sure your project is only linked against a single version of the Visual Studio runner NuGet package (xunit.runner.visualstudio).

The following steps worked for me:

(Only if you suspect there is a serious mess on your machine - in general the more common case is that the visual studio integration is simply not installed yet)

Do the DEL %TEMP%\VisualStudioTestExplorerExtensions as advised :-

PS> del $env:TEMP\VisualStudioTestExplorerExtensions

Install the NuGet Package xunit.runner.visualstudio in all test projects
- Paket:
```
  .paket\paket add nuget xunit.runner.visualstudio -i
```
  You need to end up with the following in your paket.dependencies:
```
nuget xunit.runner.visualstudio version_in_path: true
```
  Note the version_in_path: true bit is important
- Nuget: Go to Package Manager Console (Alt-T,N,O) and
```
Install-Package xunit.runner.visualstudio
```
Rebuild to make sure xunit.runner ends up in the output dir
Close Test Explorer <- this was the missing bit for me
Re-open Test Explorer (Alt-S,W,T)
Run All tests (Ctrl R, A)

edited Jun 23 '22 at 08:53

Ian Kemp

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answered Jan 30 '16 at 15:55

Ruben Bartelink

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"Close Test Explorer <- this was the missing bit for me" This is the most important step that I missed as well and spent 5 hours to figure out. Thank you, I should have paid attention to the steps :) – Esen Aug 13 '16 at 18:26
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the xunit VS runner was working for my sln. However, it had stopped showing up one day. Found out that I did not installed the VS running, and it was working probably because of the cache, left by the other sln which has the runner installed. After installing the runner, things work fine again. So don't forget to install the runner for every sln. – ZZZ May 17 '17 at 04:30
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This is unbelievable. Deleting the folder that had three other empty folders in it fixed the issue. – t3chb0t Jun 26 '17 at 10:07
@t3chb0t It probably had 50 hidden files and a wierd permission ;) (maybe it was created by a different user identity?) – Ruben Bartelink Jun 26 '17 at 15:13
Your first sentence was the key for me. The Test window showed I had the wrong version of NUnit. – Tony D Jul 05 '17 at 19:14
I missed the public keyword on my test class -_- – MartinJH Jul 21 '17 at 12:27
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@martinJH I have a self answered one for that (Linked in OP) :- https://stackoverflow.com/questions/16214684/why-is-the-xunit-runner-not-finding-my-tests/ ;) Not revealing how I discovered that though – Ruben Bartelink Jul 21 '17 at 14:30
C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\devenv /resetuserdata could also fix your problem in my experience – sebas2day Jul 25 '17 at 17:06
@seb2day not seeing any info re that suggesting a direct connection so will not edit in for now (it seems TFS Cache related https://blogs.msdn.microsoft.com/ejarvi/2005/07/14/vsts-tip-devenv-resetuserdata/ and is not documented in 2015 or 2017 anymore, although there is a *`resetsettings`* https://learn.microsoft.com/en-gb/visualstudio/ide/reference/resetsettings-devenv-exe ) – Ruben Bartelink Jul 26 '17 at 06:11
Closing and reopening Test Explorer helped me, but it didn't work the first time. I can usually get test explorer to discover tests but I haven't figured out what consistently works. – Rich Sep 05 '17 at 16:28
Removing %TEMP%\VisualStudioTestExplorerExtensions did it for me – Vanice Nov 10 '17 at 09:48
3

Really weird stuff, but deleting `%TEMP%\VisualStudioTestExplorerExtensions` and restarting VS finally worked! – Hinrich Jul 19 '18 at 15:20
Thanks mate! My issues solved by Point 3. I can't believe that the testing framework won't change accordingly. – Danny Su Oct 29 '18 at 05:43
For some reason I had to use the keyboard shortcut to run all tests (`Ctrl`+`R`,`A`) before the Test Explorer would recognize my tests. For some reason clicking the Run All button with the mouse wouldn't find any tests. – deadlydog Sep 12 '19 at 18:59
Note that on my machine with VS 2019 pro there was no `%TEMP%\VisualStudioTestExplorerExtensions` folder. Instead I had to delete `.vs\` in the solution root – Sebastian Dec 16 '19 at 22:35
Unfortunately I don't have the rep to post an answer. However, I just want to say that I encounter this issue intermittently. I did a Close Solution, then I reopened the solution, and my tests were discovered. So that's one more thing for people to try if this is just happening intermittently. – John Mar 22 '22 at 19:52

score 39 · Answer 2 · edited Sep 25 '19 at 16:00

39

None of the above solutions worked for me (dotnetcore 1.1, VS2017). Here's what fixed it:

Add NuGet Package Microsoft.TestPlatform.TestHost
Add NuGet Package Microsoft.NET.Test.Sdk

Those are in addition to these packages I installed prior:

xunit (2.3.0-beta1-build3642)
xunit.runner.visualstudio (2.3.0-beta1-build1309)

edited Sep 25 '19 at 16:00

ΩmegaMan

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answered Apr 18 '17 at 19:48

Arman Peiravi

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This helped me, i was missing xunit.runner.visualstudio package. – Ognjen Babic May 29 '17 at 07:15
My .NET 4.72 MS Test project needed `TestPlatform.TestHost` only when migrating from VS 2017 to VS 2019. – ΩmegaMan Sep 25 '19 at 16:02
This solved it for me. In the Output window, select Tests from the drop down => see message "missing TestHost" message. – datchung Jun 10 '20 at 17:01
Microsoft.NET.Test.Sdk worked for me. I didn't need to add Microsoft.TestPlatform.TestHost – KrimblKrum Oct 19 '22 at 18:13

score 36 · Answer 3 · answered Jun 13 '17 at 11:40

36

I had to change the Test Settings after changing the test projects CPU to x64. Then the tests where detected again.

answered Jun 13 '17 at 11:40

Max

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Did you see a message before that in the test discovery output? – Ruben Bartelink Jun 13 '17 at 14:57
No I didn't see any errors, it took a while to figure out. – Max Jun 14 '17 at 18:03
hmm; strange (see top of my answer - it explains where to look; normally this is flagged (though there are def cases where there simply are no messages anywhere)) – Ruben Bartelink Jun 14 '17 at 22:06
This fixed it for me. I don't know why this helps, but it does. – VSO Dec 14 '17 at 18:50
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I had to clean --> rebuild after changing. – user2023861 Apr 20 '18 at 13:01

score 27 · Answer 4 · answered Oct 31 '17 at 13:13

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Install xunit.runner.visualstudio package for the test project

answered Oct 31 '17 at 13:13

Chris Aelbrecht

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Already installed, but upgrading the version through nuget got it working again. – Alex Ayscough Mar 08 '21 at 14:58
Precise solution, works for VS 2019 – lyolikaa Dec 22 '21 at 10:23
Also works on VS 2022 – foyss Nov 30 '22 at 16:20

shaeed · Answer 5 · 2020-01-17T01:59:05.410

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Make sure that your test class is public.

edited Jan 17 '20 at 01:59

answered Oct 21 '19 at 10:40

shaeed

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thats explicitly addressed in the first proviso (I link t another question that covers that case); this Q+A is only about troubleshooting how how normally OK tests that work in other places dont work for someone righjt now in a given environment. For me this answer just confuses matters as it dilutes that distinctino. – Ruben Bartelink Oct 21 '19 at 11:03

score 15 · Answer 6 · edited Oct 16 '17 at 09:35

15

Follow this steps :

Update your MsTest.TestAdapter and MsTest.TestFramework dll's from nugget package manager.
Clean your solution
Build your solution.

edited Oct 16 '17 at 09:35

Marian Nasry

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answered Oct 16 '17 at 08:21

Venkat Ramanan

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Can you open a clone of this question and self answer please as I have done? This one is about xUnit v2 and later. Even xUnit v1 answers have no place here. You can link to it with a see also at the top of the question, or I can link to it in the question – Ruben Bartelink Oct 17 '17 at 01:42
This solution works.. Otherwise everytime i had to remove `%TEMP%\VisualStudioTestExplorerExtensions` and still sometimes i had to run the tests from console. – Venkata Dorisala Oct 19 '17 at 11:25
I am using NUnit and I solved this issue by updating NUnit3TestAdapter to the latest version via NuGet. – dpberry178 Feb 07 '18 at 00:09
Thanks for this - in my instance just had to Update-Package -reinstall MSTest.TestAdapter and the tests got picked up. – Rob Mar 05 '18 at 05:15

Tom Makin · Answer 7 · 2016-11-02T11:08:17.530

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I've been struggling with this all afternoon whilst working with an ASP Core project and xUnit 2.2.0. The solution for me was adding a reference to Microsoft.DotNet.InternalAbstractions

I found this out when trying to run the test project manually with dotnet test which failed but reported that InternalAbstractions was missing. I did not see this error in the test output window when the auto discovery failed. The only info I saw in the discovery window was a return code, which didn't mean anything to me at the time, but in hindsight was probably indicating an error.

edited Nov 02 '16 at 11:08

answered Nov 01 '16 at 21:30

Tom Makin

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"but reported a useful error" ... which was ? Also can you verify it was definitely not listed in the discovery errors window as stated in the OP - i.e. can you confidently state "I've looked in the Output window and am not seeing anything in at all under Test in the Show output from tabs." ? – Ruben Bartelink Nov 02 '16 at 03:10
1

See updated answer, I will post the return code info later on in case it is relevant. – Tom Makin Nov 02 '16 at 11:14

score 11 · Answer 8 · answered Mar 21 '17 at 16:13

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It's happened to me a couple of times - when I Clean the project and Build it again it tends to be fine.

answered Mar 21 '17 at 16:13

Liam

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any telltale messages when you look in the output window with Tests selected in the dropdown? – Ruben Bartelink Mar 21 '17 at 16:45
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None at all, it just says No tests found – Liam Mar 22 '17 at 10:10
In my case, Test Explorer was hanging on a previously failed test. If I browsed to it and tried to right click -> Run or anything then the whole VS would hang. Just doing a Clean and Rebuild cleared the test status and fixed the issue for me. – Piedone Dec 27 '19 at 20:45
May I add that simply building (i.e. F6) won't help, you need to right-click on the solution in VS Solution Explorer and click Rebuild Solution. – Piedone Dec 27 '19 at 23:18

Chamila Maddumage · Answer 9 · 2019-05-05T11:21:53.527

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I had the same issue with Visual Studio 2019. Just Installed the following NuGet packages and the issue was solved.

1). xUnit

2). xunit.runner.visualstudio

3). Microsoft.TestPlatform.TestHost

4). Microsoft.NET.Test.Sdk

edited May 05 '19 at 11:21

answered May 05 '19 at 10:57

Chamila Maddumage

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score 8 · Answer 10 · answered Jun 18 '17 at 20:33

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After spending 2 days... none of the above worked for me. The only "solution" was: Go to project properties -> Build Tab. Then click Advanced button on the right bottom corner of the pane. Change "Debug Info:" to "full" and click OK.

Here are the screen shots:

answered Jun 18 '17 at 20:33

curiousBoy

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sounds painful. Thanks for sharing and hope it helps someone some day. However I have to say: I can't think of any reason for the debug info level to affect the discovery process so I can only say "I don't think that was what actually shot the bear" - let's hope I'm wrong though ;) – Ruben Bartelink Jun 19 '17 at 18:38
@RubenBartelink completely agree with you, that is why I mentioned "solution" in a quote :) but weird enough, it worked right away once I did this. – curiousBoy Aug 18 '17 at 04:04
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Thank you very much. This was also the fix for me :) – Babulaas Jan 15 '18 at 11:10

score 7 · Answer 11 · edited Feb 25 '18 at 08:04

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The reason in my case was the target build was not the same between project debugger and test runner. To unify those elements:

Test>Test Settings>Default Processor Architecture. then select either X64 or X86.
Project>(your project)Properties>Build(tab)>platform target.

After they are identical, rebuild your solution then test methods will appear for you.

edited Feb 25 '18 at 08:04

Ruben Bartelink

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answered Feb 25 '18 at 07:28

Jawad Sabir

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score 6 · Answer 12 · answered Sep 07 '17 at 05:18

I am using xUnit 2.2.0.

My issue was my solution was not able to find certain dlls and app.config was trying to resolve them. The error was not showing up in the test output window in Visual Studio.

I was able to identify the error when I installed xunit.runner.console and tried to run the tests through command line.

How to run xunit tests in CLI.

score 5 · Answer 13 · answered Mar 05 '18 at 12:16

I can provide a solution for an edge case I ran into a few days ago. It's not gonna be the solution that fits all of the scenarios described above, however, for the edge case I had it fixed it.

I had the same issue with most recent VS 2017 (version 15.5.7) and XUnit 2.3.1. The xunit.runner.visualstudio package was installed, however, the tests didn't show up in VisualStudio's built-in test explorer.

I was working on a legacy project that was targeting .NET framework 4.5. However, beginning with version 2.2. XUnit does not support .NET frameworks lower thant 4.5.2 (see Release Notes - XUnit 2.2: February 19, 2017

Changing the test project's target framework to a version >= 4.5.2 worked for me. You don't have to change the project's version that you're testing, it's just about the test project itself.

score 3 · Answer 14 · answered Jul 14 '17 at 09:35

3

This can also be due to the build check box not being ticked for the current platform project in the build configuration. Click Build | Configuration manager, then make sure the test projects have a tick in the build column for the platform that you're using (for example 'x86').

This was definitely the solution that worked for me.

answered Jul 14 '17 at 09:35

cd747

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I would upvote this if it was on https://stackoverflow.com/questions/16214684/why-is-the-xunit-runner-not-finding-my-tests/ as this is not xunit2 specific and a good checklist element – Ruben Bartelink Jul 14 '17 at 10:56

vullnetyy · Answer 15 · 2021-05-15T20:12:06.167

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Do make sure that you haven't written your unit tests in a .NET Standard 2.0 Class Library. The visualstudio runner does not support running tests in netstandard2.0 class libraries at the time of this writing.

Check here for the Test Runner Compatibility matrix:

https://xunit.net

edited May 15 '21 at 20:12

answered Sep 05 '17 at 09:29

vullnetyy

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Both links are dead. – joelmdev May 14 '21 at 19:45

score 3 · Answer 16 · answered Oct 01 '17 at 23:45

3

Ran into a similar problem with VS not discovering test methods. In my case I had the static keyword with the method, which I removed and it worked.

[TestMethod]

Before: public static void Test1()

After: public void Test1()

answered Oct 01 '17 at 23:45

live-love

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I'd really prefer if this was not here as this is about otherwise correct tests that can't be found in a particular instance of VS. I have a self-answered one re why an xunit test can't be discovered: https://stackoverflow.com/questions/16214684/why-is-the-xunit-runner-not-finding-my-tests. May I suggest you create a why cant my MSTest test be picked up (by VS if you want). (As you prob know, this particular concern does not even apply to xUnit which is another reason why, helpful as it is, your answer does not belong here) – Ruben Bartelink Oct 02 '17 at 07:46
MSTest did not find my tests because the class access modifier was internal. – Abdul Saboor Feb 13 '20 at 10:36

stakx - no longer contributing · Answer 17 · 2017-05-07T18:36:33.983

There is one other reason that can cause Test Explorer not showing any tests, and it has to do with the new portable .pdb file format introduced with Visual Studio 2017 / for .NET Core which can break some VS tooling. (Background: See the bug report "Mono.Cecil causes OutOfMemoryException with new .csproj PDBs".)

Are your tests not found because of the new portable `.pdb` (debug symbols) format?

Open the Output window.
Change drop-down selection for Show output from to Tests.
If you see output like to the following (possibly repeated once for each of your tests), then you've got the problem described in this answer:
```
Exception System.OutOfMemoryException, Exception converting <SignatureOfYourTestMethod>
Array dimensions exceeded supported range.
```

If yes, do this to resolve the problem:

Open your test project's Properties (select the test project in Solution Explorer and press Alt+Enter).
Switch to the Build tab.
Click on the Advanced... button (located at the very end of that tab page).
In the drop-down labelled Debugging information, choose none, pdb-only, or full, but NOT portable. It is this last setting that causes the tests to not be found.
Click OK and clean & rebuild your project. If you want to be extra sure, go to your test project's output directory and clean all .pdb files before rebuilding. Now your tests should be back.

score 2 · Answer 18 · answered Aug 24 '17 at 17:50

In my case, I had 2 different test projects in the solution. Project 1 tests could be found, but Project 2 tests could not. I found that first Unloading the test Project 1, then closing VS > clearing my temp files > re-open solution > rebuild, allowed VS to discover my Project 2 tests.

I'm assuming something must be conflicting between the two test projects and this was the quickest way to get me up and running in a few minutes. The kinks can be worked out later :).

score 2 · Answer 19 · answered Feb 01 '18 at 12:52

I tried most of the suggestions above and nothing worked. In my case, I'm on a team and tests were appearing for other devs for the same solution. So, I attempted just deleting my .vs folder, but no luck there either.

I ended up deleting my local folder entirely and re-cloning the repo. That solved it for me.

score 2 · Answer 20 · answered Feb 20 '18 at 09:34

I was suffering from this problem for long times.

I had about 100 projects different version was deployed in different server.
Updating xunit from 2.2.0 to 2.3.1 was not a solution because build was failing in 2.3.1.

Then I just updated xunit.runner.visualstudio to 2.3.1 and everything started to work fine. I have used this command in my package manager console to updated my xunit.runner.visualstudio package

Get-Project ComapanyName.ProjectName.*.Tests | Install-Package xunit.runner.visualstudio -Version 2.3.1

score 2 · Answer 21 · answered May 15 '19 at 03:20

2

Close all Visual Studio instances
Go to %TEMP%\VisualStudioTestExplorerExtensions\
Delete specrun related folders
Try again

let me know, thanks

answered May 15 '19 at 03:20

alvarodoune

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score 2 · Answer 22 · answered Nov 10 '21 at 08:37

2

I hope my answer will be helpful for some of you: In most of the cases when my unit tests were not discovered I had to change the the test class access modifier to public. When add a new class (Shift+Alt+C) the default access modifier is internal and most of the time I forget to change it.

answered Nov 10 '21 at 08:37

Catalin Enache-Stoian

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This set of reasons, which will make them not work on anyone's machine anywhere (except TestDriven.net will half-run them) is covered under the question linked to in the OP: https://stackoverflow.com/questions/16214684/why-is-the-xunit-runner-not-finding-my-tests/ – Ruben Bartelink Nov 10 '21 at 12:16
Please don't add "thank you" as an answer. Once you have sufficient [reputation](https://stackoverflow.com/help/whats-reputation), you will be able to [vote up questions and answers](https://stackoverflow.com/help/privileges/vote-up) that you found helpful. - [From Review](/review/late-answers/30303954) – Bakar Nov 10 '21 at 13:35

score 1 · Answer 23 · answered Apr 03 '17 at 15:45

The most common culprit for me has been Visual Studio trying to run the tests using a different architecture than the library it's testing. Unfortunately there are multiple places where it seems this can go wrong.

In VS 2017, try creating a Run Settings file, e.g. Default.runsettings in your test project. If your main lib is x64, the contents should be:

<?xml version="1.0" encoding="utf-8"?>
<RunSettings>
  <RunConfiguration>
    <TargetPlatform>x64</TargetPlatform>
  </RunConfiguration>
</RunSettings>

Then choose this file from Test -> Test Settings -> Select Test Settings File.

Then, under Test -> Test Settings, Default Processor Architecture, choose the correct architecture again.

Be sure to Clean and Build the entire solution. You may need to close and reopen the Test Explorer window. Look for any additional errors in the Output -> Test window, for more clues about incorrect architecture types.

FYI additional Test Settings entries can be found here.

score 1 · Answer 24 · answered Jun 20 '17 at 13:30

Happend to me when i took my first first walking attempts with IntelliTest in VS 2017.

Sometimes, when the test project gets auto-created by IntelliTest, the assembly reference to Microsoft.ExtendedReflection (...\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\Common7\IDE\Extensions\Microsoft\Pex\Microsoft.ExtendedReflection.dll) is missing. When added, the generated Tests will show up in test explorer after recompile.

score 1 · Answer 25 · answered Jun 20 '17 at 14:22

1

Disclaimer: it is not about xunit with visual studio 2015, but Visual Studio 2017 with a UWP unit test application (MSTest). I got to this thread searching the same thing so maybe someone else will do the same :)

The solution for me was to update the nuget packages for MSTest.TestAdapter and MSTest.TestFramework. It seems that when you create a unit test app for UWP you don't automatically get the latest versions.

answered Jun 20 '17 at 14:22

Alex Albu

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I'd suggest asking a self answered question as I did is the best way to sequester such info - feel free to copy paste my entire question and s/xUnit/MSTest/ if you think it makes sense ;) – Ruben Bartelink Jun 20 '17 at 23:28

score 1 · Answer 26 · answered Oct 15 '17 at 09:11

1

My problem was resolved by installing the nuget xunit.runner.visualstudio

answered Oct 15 '17 at 09:11

kDar

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score 1 · Answer 27 · answered Nov 30 '17 at 03:54

In my case I have multiple test projects in the same solution, and only one of the projects was not displaying the "Test Explorer"

I went to the "Manage Nuget Package for Solution" by right-clicking on the solution.

I noticed under the "Consolidate" tab there was some "Test" nuget packages that were out of sync between the projects. I clicked on "Install" and my missing tests showed up.

score 1 · Answer 28 · edited Mar 25 '19 at 07:48

1

Here is the solution that worked for us. Not the best but maybe one can benefit.

Background:

Our scripts were developed with VS 2013 and used NUnit VS Adapter 2.1..
Recently we migrated to VS 2017 and when open the same solution - test wouldn't show in the Test Explorer

Upon Build we would see this message:

[Informational] NUnit Adapter 3.10.0.21: Test discovery starting
[Informational] Assembly contains no NUnit 3.0 tests: C:\ihealautomatedTests\SeleniumTest\bin\x86\Debug\SeleniumTest.dll
[Informational] NUnit Adapter 3.10.0.21: Test discovery complete

Solution (temporary):

Uninstall NUnit Adapter 3.10...
Install NUnit VS Adapter 2.1..

Now the Tests are shown.

edited Mar 25 '19 at 07:48

Zoe

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answered May 29 '18 at 17:30

Andrew Homsky

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Please extract your (at least seemingly) new question to its own post to make this a clear answer :) – geisterfurz007 May 29 '18 at 18:51
... Entitled "why is the NUnit TestAdapter v3 not seeing my NUnit v2 tests? and a) ping here b) an put a "see also " at top (even if it is slightly tenuous), but I'd like this answer removed as it does not fit well with the `xUnit v2 tests` in the title. – Ruben Bartelink May 30 '18 at 02:02

score 0 · Answer 29 · answered Jul 17 '17 at 15:54

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Also check if a completely empty app.config file (completely blank with absolutely no markup) is within the test project. This was the culprit in my case.

answered Jul 17 '17 at 15:54

Gopal Krishnan

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score 0 · Answer 30 · answered Jul 20 '17 at 16:09

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In my case, I created a new "Solution Configuration" like shown in the image. So when I select my custom one as "Prod", it doesnt recognize TestMehods for some reason. Changing back to "Debug" solves the problem

answered Jul 20 '17 at 16:09

Emil

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score 0 · Answer 31 · answered Jul 20 '17 at 21:49

0

I don't know if some of you also use JustMock, but I had to disable the profiler in VS 2017 for test detection to work.

answered Jul 20 '17 at 21:49

chrisdrobison

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Hmmm. If you turn it back on, does it immediately fail again? – Ruben Bartelink Jul 21 '17 at 05:32
Yep. If I close the solution, turn on the profiler and get back in, test detection fails. – chrisdrobison Jul 24 '17 at 18:38

score 0 · Answer 32 · answered Oct 30 '17 at 13:26

0

I had many projects of different type in my solution and I could not run the Xunit test project. I unloaded all of them except my Xunit project and then rebuild the solution the tests appeared in visual studio and I could run them.

answered Oct 30 '17 at 13:26

Youcef Kelanemer

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Using Visual studio 2017 and after upgrading package to xunit.runner.visualstudio.2.3.1, Xunit tests appeared next to Unittests. – Youcef Kelanemer Nov 01 '17 at 13:18

score 0 · Answer 33 · answered Nov 08 '17 at 07:00

0

You need to update your all packages when you are move VS2015 to VS2017 for discover test in test explorer.

answered Nov 08 '17 at 07:00

Sachin

1
1

score 0 · Answer 34 · answered Dec 05 '17 at 04:18

0

I Cleared Temp, %Temp% and Prefetch. Then tried reopening VS and was able to find the test methods

answered Dec 05 '17 at 04:18

Venkat Ramanan

217
2
8

score 0 · Answer 35 · answered Jan 17 '18 at 13:10

0

I have test project A and B. Tests in Project A where discovered but the Discovery never stopped for B. I had to manually kill TestHost to make stop.

I did a lot of things this page describes even to the point that I'm unsure as to wheter this was the solution.

Now it worked and the thing I did was to open the Solution and NOT have the Test Explorer up. Instead I just checked the Output window for Tests and I could see the discovery process end and the number of test where equal to A+B. After this, I opened the Test Explorer and then both A and B where present. So:

Uninstall and Install the latest xUnit stuff correctly. Delete the %temp% as mentioned above, Add NuGet Package "Microsoft.TestPlatform.TestHost" Add NuGet Package "Microsoft.NET.Test.Sdk", restart but only check the Tests Output. If it works u'll see

answered Jan 17 '18 at 13:10

Tomas Hesse

385
3
10

Oh, and check the Test target Architecture. x86 or x64 and make sure project and references are inline with your choisce – Tomas Hesse Jan 17 '18 at 13:12
Hm, not sure I buy the uninstalling and reinstalling packages or the need for `Microsoft.TestPlatform.TestHost` or `Microsoft.NET.Test.Sdk` but I appreciate the frustration, the documenting of stuff you did in order to reach the endline in your context (will +1 should I manage to verify this as a specific step that makes a difference) – Ruben Bartelink Jan 17 '18 at 13:57
Can you mention your VS version in this ? While I'm trying to keep the question and my self-answer version-independent, I suspect anyone reading this and guessing whether it's worth a shot would benefit from that context being edited into your answer. – Ruben Bartelink Jan 17 '18 at 13:58
I can add that today it DID NOT work at all!! It is VS 2017 Enterprise. I gave it up today. I unloaded the project and the test will not be run. There is probably something wrong with the project itself. Read somewhere it could be due to async tests in combination with exceptions (NotImplemented) maybe but I'm done with it. There's no valueable info.It just hangs on discovery and some times I have seen the test but not today. – Tomas Hesse Jan 18 '18 at 14:56
That sound like a proper pain. If discovery is actually hanging (ie. Test window of Output panel is showing no completion and no errors), it may be useful to attach another copy of VS (via attach to process, Ctrl-Alt-P) to the vstest.discovery.exe host exe within which that takes place. However I suspect that there should be some form of timeout and have not ever heard of anyone actually doing something like this. I hope your problems get simpler some time soon :( – Ruben Bartelink Jan 18 '18 at 21:13

score 0 · Answer 36 · answered Jul 03 '20 at 08:49

0

Make your test class as public and add annotation as [TestClass]

answered Jul 03 '20 at 08:49

Raunak Mali

42
2

1

Please remove - this question is about xunit, and even if it mentioned the Xunit attributes, that's excluded in the question – Ruben Bartelink Jul 03 '20 at 12:07

score 0 · Answer 37 · answered Oct 19 '21 at 22:27

0

Right click on Test project and select Properties. Change Target framework property from 1.1 to something else (I used 3.1) and everything will run as 1.1 isnt covered anymore :P

answered Oct 19 '21 at 22:27

Andrew Day

563
10
23

Thanks, I will check it out as soon as I get the opportunity. If it works will let you know. – yogibear Oct 20 '21 at 11:52

score 0 · Answer 38 · answered Nov 03 '21 at 19:03

Open Outputs -> Tests and see what the error is. In my case, I had this error message:

The framework 'Microsoft.AspNetCore.App', version '5.0.0' (x64) was not found.

After installing .Net SDK 5.0, tests worked immediately: https://dotnet.microsoft.com/download/dotnet/thank-you/sdk-5.0.402-windows-x64-installer

score 0 · Answer 39 · answered Mar 10 '23 at 15:51

0

Make sure your project is not open as a "folder" instead, click the .sln file within the folder.

Once the project is opened using the .sln file, you should be able to build then subsequently run the xUnit tests.

answered Mar 10 '23 at 15:51

Max Alexander Hanna

3,388
1
25
35

score -1 · Answer 40 · answered Jan 12 '21 at 14:44

-1

It was that easy for me - the class which contains the test methods must be public. :)

answered Jan 12 '21 at 14:44

Anna Nikolova

57
2
8

This solution has already been posted [on this page](https://stackoverflow.com/a/58484586/2227743). Please don't add duplicates. – Eric Aya Jan 12 '21 at 16:46
Hi, I excluded this reason in at the start of the question - this one: https://stackoverflow.com/questions/16214684/why-is-the-xunit-runner-not-finding-my-tests/ is a similar one about why it doesn't work _for anyone_. This question is about "why is in not working on my machine, it normally works" ?! – Ruben Bartelink Jan 13 '21 at 09:50

score -1 · Answer 41 · answered Jun 14 '21 at 06:38

-1

check the type of test.cs files in property window and it is c# compiler. in my case i have accidentally changed it to the embedresource and faced this issue.

answered Jun 14 '21 at 06:38

Ajay Kopperla

199
2
5

1

This would prevent it working on any machine (the OP excludes such reasons); such reasons are catalogued in https://stackoverflow.com/questions/16214684/why-is-the-xunit-runner-not-finding-my-tests/ - can you place the answer there instead please? – Ruben Bartelink Jun 14 '21 at 08:25
I agree, but this is what i faced in my scenario and none of them worked for me and finally realized that i had accidentally changed. i know this is very rare case but happened to me – Ajay Kopperla Jun 17 '21 at 09:40
Yes, but please log that as an answer to the other question linked in this question! It answers that question, it does not answer this. This question says "it works for everyone but be, what could it be". The other one says "my test wont work no matter what I do" – Ruben Bartelink Jun 18 '21 at 08:02

Why is the Visual Studio 2015/2017/2019 Test Runner not discovering my xUnit v2 tests

41 Answers41

Are your tests not found because of the new portable .pdb (debug symbols) format?

If yes, do this to resolve the problem:

Linked

Are your tests not found because of the new portable `.pdb` (debug symbols) format?