Replace Console.WriteLine in NUnit

Question

I haven't done much with NUnit before, but I just wanted to dump some text to a window in a console type fashion. For example:

Console.WriteLine("... some information...");

That won't work of course because NUnit is driving things.

I'm in the middle of building some unit tests and want to dump a list of variable values for inspection during debug. It isn't strictly a unit test if I need to do this, I admit that, but it would be convenient.

For one of the answers, it is the same as in *[How do I get nunit3-console to output my debug to screen?](https://stackoverflow.com/questions/46405753/how-do-i-get-nunit3-console-to-output-my-debug-to-screen-on-a-windows-box)* - *"in NUnit 3, you should use TestContext.WriteLine(...) in your tests"*. It [works on Linux](https://stackoverflow.com/questions/46405753/how-do-i-get-nunit3-console-to-output-my-debug-to-screen-on-a-windows-box#comment110657051_46407376) as well. — Peter Mortensen, Jul 10 '23 at 09:35

score 72 · Answer 1 · edited Jul 27 '20 at 15:08

72

In NUnit v3, you can also write to the test results output for debugging with

TestContext.Out.WriteLine("Message to write to log");

edited Jul 27 '20 at 15:08

Peter Mortensen

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answered Aug 03 '17 at 19:25

Ashitakalax

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This is the type of functionality I was looking for. Works in Debug *and* Release. Visual Studio 2017(15.8.7) – Aaron Jordan Oct 19 '18 at 21:26
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Even better is TestContext.Progress.WriteLine(string) for continuous output to the Output window of Visual Studio 2017. – Pebermynte Lars Oct 03 '19 at 15:43
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I don't get anything in output window when running a unit test nor in the output log – John Demetriou May 06 '20 at 12:07
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Or, even shorter [`TestContext.Write(...)`](https://docs.nunit.org/articles/nunit/writing-tests/TestContext.html#write) and [`TestContext.WriteLine(...)`](https://docs.nunit.org/articles/nunit/writing-tests/TestContext.html#writeline). – nevermind Mar 15 '21 at 12:24
Where the output will show in VS Code? – tarekahf Mar 19 '22 at 04:22
I'm not sure on VS Code, this was focused on Visual Studio's. However, you may check the Test Explorer log. That might have it, or some similar option. – Ashitakalax Mar 21 '22 at 21:05

score 56 · Accepted Answer · edited Dec 30 '20 at 00:23

56

You can see the console output. You just have to select the "Text Output" tab in the NUnit GUI runner.

Enter image description here

If you are using the ReSharper test runner, the console output should be displayed. Ensure that the test runner output window is displayed by clicking the "Show Output" button in the test runner tool bar:

Enter image description here

You should then get something as follows:

Enter image description here

edited Dec 30 '20 at 00:23

Pang

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answered Jul 26 '11 at 16:46

Tim Lloyd

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thanks for pointing this out. I now realise that I need to have nunit installed. Currently it is running via an assembly reference that came with the project, and I think resharper has hooks into it. – sgtz Jul 26 '11 at 17:07
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@sgtz Are you running your NUnit tests via the ReSharper test runner? If so, the output should be in the output window of the test runner. Please see my update. – Tim Lloyd Jul 26 '11 at 17:12

score 35 · Answer 3 · answered Jul 26 '11 at 16:46

35

Try using System.Diagnostics.Debug.WriteLine instead.

answered Jul 26 '11 at 16:46

Paul Creasey

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This applied only in Debug Mode. In Release Mode it's not working. – M.Hassan Mar 08 '17 at 20:10
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``System.Diagnostics.Trace.WriteLine`` will output in release builds as well. – codeape Nov 01 '18 at 13:21

score 15 · Answer 4 · edited Jul 27 '20 at 15:12

15

In Visual Studio 2017, in the Test Explorer window, there is a link, Output, in the lower Test pane. This brings up anything written to the console during that unit test.

edited Jul 27 '20 at 15:12

Peter Mortensen

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answered Nov 16 '17 at 23:53

LostNomad311

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Nop, nothing there for me, nothing of my writeline content at least – John Demetriou May 06 '20 at 12:08

MrClan · Answer 5 · 2022-05-12T15:18:25.300

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Use the Test-Output view.

Steps:

Open Test Explorer
Select any particular test
Run it if it has never been run.
Click on the output link on the test results pane.

There is no need to replace Console.WriteLine with anything as this view logs messages from:

Console.WriteLine

Trace.WriteLine

Debug.WriteLine

TestExplorer.Out.WriteLine

edited May 12 '22 at 15:18

answered Mar 07 '19 at 09:07

MrClan

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This is only applicable for failing tests, how about for passing tests? – Mark Aug 30 '19 at 23:46
@Mark I see it for passing tests too. Maybe your issue is somewhere else? – Pebermynte Lars Sep 13 '19 at 10:31
Is "Test-Output" literal? – Peter Mortensen Jul 27 '20 at 15:19
@PeterMortensen No. As highlighted in the screenshot, it is the **output** button inside the view where test's output/results are displayed. – MrClan May 12 '22 at 15:17

Replace Console.WriteLine in NUnit

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