I've got a large acceptance test (~10 seconds per test) test suite written using NUnit. I would like to make use of the fact that my machines are all multiple core boxes. Ideally, I'd be able to have one test running per core, independently of other tests.
There is PNUnit, but it's designed for testing for threading synchronization issues and things like that, and I didn't see an obvious way to accomplish this.
Is there a switch/tool/option I can use to run the tests in parallel?
If you want to run NUnit tests in parallel, there are at least 2 options:
NCrunch offers it out of the box (without changing anything, but is a commercial product)
NUnit 3 offers a Parallelizable attribute, which can be used to denote which tests can be run in parallel
NUnit version 3 will support running tests in parallel:
Adding the attribute to a class: [Parallelizable(ParallelScope.Self)] will run your tests in parallel.
• ParallelScope.None indicates that the test may not be run in parallel
with other tests.
• ParallelScope.Self indicates that the test
itself may be run in parallel with other tests.
• ParallelScope.Children indicates that the descendants of the test may
be run in parallel with respect to one another.
• ParallelScope.Fixtures indicates that fixtures may be run in parallel
with one another.
NUnit Framework-Parallel-Test-Execution
If your project contains multiple test DLLs you can run them in parallel using this MSBuild script. Obviously you'll need to tweak the paths to suit your project layout.
To run with 8 cores run with: c:\proj> msbuild /m:8 RunTests.xml
RunTests.xml
<?xml version="1.0" encoding="utf-8"?>
<Project DefaultTargets="RunTestsInParallel" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
<Import Project="$(MSBuildExtensionsPath)\MSBuildCommunityTasks\MSBuild.Community.Tasks.Targets"/>
<PropertyGroup>
<Configuration Condition=" '$(Configuration)' == '' ">Release</Configuration>
<Nunit Condition=" '$(Nunit)' == '' ">$(MSBuildProjectDirectory)\..\tools\nunit-console-x86.exe</Nunit>
</PropertyGroup>
<!-- see http://mikefourie.wordpress.com/2010/12/04/running-targets-in-parallel-in-msbuild/ -->
<Target Name="RunTestsInParallel">
<ItemGroup>
<TestDlls Include="..\bin\Tests\$(Configuration)\*.Tests.dll" />
</ItemGroup>
<ItemGroup>
<TempProjects Include="$(MSBuildProjectFile)" >
<Properties>TestDllFile=%(TestDlls.FullPath)</Properties>
</TempProjects>
</ItemGroup>
<MSBuild Projects="#(TempProjects)" BuildInParallel="true" Targets="RunOneTestDll" />
</Target>
<Target Name="RunOneTestDll">
<Message Text="$(TestDllFile)" />
<Exec Command="$(Nunit) /exclude=Integration $(TestDllFile) /labels /xml:$(TestDllFile).results.xml"
WorkingDirectory="$(MSBuildProjectDirectory)\..\bin\Tests\$(Configuration)" />
</Target>
</Project>
Update
If I were answering this question now I would highly recommend NCrunch and its command line test running tool for maximum test run performance. There's nothing like it and it'll revolutionise your code-test-debug cycle at the same time.
As an alternative to adding the Parallelizable attribute to every test class:
Add this into the test project AssemblyInfo.cs class for nunit3 or greater:
// Make all tests in the test assembly run in parallel
[assembly: Parallelizable(ParallelScope.Fixtures)]
In this article it is mentioned that in order to speed up tests the poster runs multiple instances of NUnit with command parameters specifying which tests each instance should run.
FTA:
I ran into an odd problem.
We use nunit-console to run test on
our continuous integration server.
Recently we were moving from Nunit
2.4.8 to 2.5.5 and from .Net 3.5 to 4.0. To speed up test execution we run multiple instances of Nunit in
parallel with different command line
arguments
We have two copies of our test assemblies and the nunit binaries in
folder A and B.
In folder A we execute
nunit-console-x86.exe Model.dll
Test.dll /exclude:MyCategory
/xml=TestResults.xml
/framework=net-4.0 /noshadow
In folder B we execute
nunit-console-x86.exe Model.dll
Test.dll /include:MyCategory
/xml=TestResults.xml
/framework=net-4.0 /noshadow
If we execute the commands in sequence
both run successfully. But if we
execute them in parallel only one
succeeds. As far as I can tell it's
the one that first loads the test
fixtures. The other fails with the
message "Unable to locate fixture".
Is this problem already known? I could
not find anything related in the bug
list on launchpad. BTW Our server runs
Windows Server 2008 64-bit. I could
also reproduce the problem on Windows
7 64-bit.
Assuming this bug is fixed or you are not running the newer version(s) of the software mentioned you should be able to replicate their technique.
Update
TeamCity looks like a tool you can use to automatically run NUnit tests. They have an NUnit launcher discussed here that could be used to launch multiple NUnit instances. Here is a blog post discussing the mergind of multiple NUnit XML results into a single result file.
So theoretically you could have TeamCity automatically launch multiple NUnit tests based on however you want to split up the workload and then merge the results into a single file for post test processing.
Is that automated enough for your needs?
Just because PNUnit can do synchronization inside test code doesn't mean that you actually have to use that aspect. As far as I can see there's nothing to prevent you from just spawning a set and ignoring the rest till you need it.
BTW I don't have the time to read all of their source but was curious to check out the Barrier class and it's a very simple lock counter. It just waits till N threads enter and then sends the pulse for all of them to continue running at the same time. That's all there is to it - if you don't touch it, it won't bite you.
Might be a bit counter intuitive for a normal threaded development (locks are normally used to serialize access - 1 by 1) but it is quite a spirited diversion :-)
You can now use NCrunch to parallelize your unit tests and you can even configure how many cores should be used by NCrunch and how many should be used by Visual Studio.
plus you get continuous testing as a bonus :)
It would be a bit of a hack, but you could split the unit tests into a number of categories. Then, start up a new instance of NUnit for each category.
Edit: It looks like they have added a /process option to the console app. The command-line help states this is the "Process model for tests: Single, Separate, Multiple". The test runner also appears to have this feature.
Edit 2: Unfortunately, although it does create separate processes for each assembly, the process isolation option (/process from the command line) runs the agents one at a time.
Since the project hasn't been mentioned here, I would like to bring up NUnit.Multicore. I haven't tried the project myself, but it seems to have an interesting approach to the parallel test problem with NUnit.
You can try my small tool TBox or console parallel Runner or even plugin to do distributed calulations, which also can run unit tests on the set of PCs SkyNet
TBox is created to simplify work with big solutions, which contains many projects. It supports many plugins and one of them provide ability to run NUnit tests in parallel. This plugin does not require any changes to your existing tests.
Also it support:
Cloning of the folder with unit test (if your tests changes local data),
Synchronizations of the tests (for example if your tests on
testfixtureteardown kills all dev servers or chromerunner for qunit )
x86 mode and Admin privileges to run tests
Batch run - you can run tests for many assemblies in parallel
Even for single thread run, works faster than standart nunit runner, if you have much small tests.
Also this tool supports command line tests runner (for parallel run) and you can use it with continuous integration.
I have successfully used NUnit 3.0.0 beta-4 to run tests in parallel
Runs on build server
Runs Selenium tests
Has Visual Studio support
no Resharper support yet
Thanks for peers answer.
Gotchas:
Parallelizable attribute is not inherited, so it has to be specified on the test class.
You can use following PowerShell command (for NUnit3, for NUnit2 change runner name):
PS> nunit3-console (ls -r *\bin\Debug\*.Tests.dll | % FullName | sort-object -Unique)
Presented command runs all test assemblies in single nunit instance, which allows to leverage engine built-in parallel test run.
Remarks
Remember to tweak directory search pattern. Given example runs only assemblies ending with .Tests.dll and inside \bin\Debug directories.
Be aware of Unique filtering - you may not want to have it.
To achieve level of parallelism ensure to do these two:
1)Nunit Explorer - Settings - Run tests in parallel
2)LevelOfParallelism
This is an assembly-level attribute used to specify the level of parallelism, that is, the maximum number of worker threads executing tests in the assembly.
In Assemblyinfo.cs, set
[assembly:LevelOfParallelism(N)] => here N is number
Related
I have a TeamCity build configuration that builds a C# project, runs some unit tests, and then does some extra things. My question is: Can I get information about my unit test run stored into build configuration variables (i.e. how many tests were run, how many were successful, how many failed, how many were skipped) so that I can then check these variables in a PowerShell script in later build steps and perform different actions depending on how many tests have passed?
AFAIK the best way is to ask these information directly to teamcity server using its REST API (pay attention, maybe the build locator could be a little be tricly to be found, if the build is still running).
By other hand, you can parse your NUnit test result file (or files if you run more than one NUnit test runner step in your build) inside your build agent machine.
Currently, for our selenium UI tests, we are reading the available selenium server browsers to decide on the number of threads we will run our tests with and we pass the "workers" parameter when starting nunit console runner.
I am now migrating our automation to .net core. Unfortunately nunit console does not support .net core yet and we are now using "dotnet test" command to run the tests, which still runs the nunit tests.
I searched a lot, but could not find how to pass the "workers" parameter to nunit? There are other parameters for "dotnet test" for threads, but they do not allow you to run with more threads than there are cpu cores. Please note that I don't want to hardcode the number of threads in the assemblyInfo, since we often use different number of threads per our runs, depending on the selenium server against which the tests are run.
I tried using the .runsettings settings file when running the test command, but it seemed the parameter was not detected there too. What I end up with is a test run with threads equal to the number of cpu cores on the machine, but I need a lot more threads than that.
Versions:
.net core 2.2
NUnit 3.11
NUnit3TestAdapter 3.12
According to https://github.com/nunit/docs/wiki/Tips-And-Tricks#NumberOfTestWorkers you can set number of workers using setting NumberOfTestWorkers.
You can do it in two ways: set it in .runsetting file and pass it with --settings option, or you can pass key-value pair right in a command line after "--" separator.
dotnet test Project.csproj -- NUnit.NumberOfTestWorkers=10
I tried using the .runsettings settings file when running the test command, but it seemed the parameter was not detected there too.
To get it working you just need to check that your project references NUnit3TestAdapter and that your .runsettings file has proper structure like this.
<?xml version="1.0" encoding="utf-8"?>
<RunSettings>
<NUnit>
<NumberOfTestWorkers>10</NumberOfTestWorkers>
</NUnit>
</RunSettings>
I'm using VS 2013 and NUnit.
I'm running my tests in Resharpers's TestRunner GUI - this thing:
I have multiple projects (Solution.Foo, Solution.Bar, etc), and tests for each project in Solution.Foo.Tests, Solution.Bar.Tests, etc.
One of my tests in Foo.Tests is accessing a file, located in the Solution.Foo.Tests Folder.
I use TestContext.CurrentContext.TestDirectory to locate it and when I run that test it all works just fine.
If I run the whole suite of tests in Foo.Tests, (i.e. click on Solution.Foo.Tests in the Runner GUI and run) then it's fine.
But if I select one test from Bar.Tests and my file-reading test from Foo.Tests, then it fails, because suddenly TestDirectory is set to a path in Bar.Tests.
It's as if NUnit set TestDirectory once when it starts running a collection of tests, determined by where the first test is and then never updates it again.
Any ideas what's going on and how to fix it?
ReSharper has an optimisation for speed, by sharing an AppDomain across multiple assemblies. The downside to this is that it will pick an arbitrary assembly to be the main one, which means the directory can be wrong (and it might not pick up the correct app.config, too).
You can disable the optimisation in ReSharper → Options → Unit Testing, by checking the "Use separate AppDomain for each assembly with tests".
Is it possible to run NCover automatically from code instead of running NCover manually or via command line?
Here is the scenario, I have written a few tests, I execute all the tests and after the tests are completed, NCover should run automatically for that particular test project and store the coverage report as an XML in a location.
Is this possible to do? Kindly help.
Running NCover from the command line was the only option with NC3. When we updated NC4 the default works like this --> you create a project, the NCover service watches for a process to start that meets the match rules defined in the project, and then collects coverage on it.
This doc may be of some help: http://www.ncover.com/support/docs/desktop/user-guide/coverage_scenarios/how_do_i_collect_data_from_nunit
If you have more questions, please reach out to us at support#ncover.com.
I have 13 separate but related architecture assemblies, and 13 separate NUnit test assemblies, each one containing all the test fixtures for its matching architecture assembly. I am using NUnit 2.5.2 (latest version currently).
I can run each test assembly separately in the NUnit GUI and all the tests pass. However, when I come to combine them into a single NUnit project file, NUnit insists on applying a single config file to the whole test run. This won't work because each test assembly requires different config. I can't merge them into one "uber-config" file because some of the sections are mutually exclusive. I have tried running each assembly in the project in separate AppDomains, and also separate processes, but in both cases it fails to use the DLL-specific config file, so all the tests crash and burn.
I have done a Google search but so far I have not found any indication that NUnit supports this scenario. Am I right, or have I missed something?
I have tried my hardest to re-architecture the tests so that they could share the same config file, but I've had to admit defeat on that front.
NUnit 2.5 has as setting where you can enable each assembly to run in a separate AppDomain. By doing this, NUnit will load the config for the assembly and not the one for the .nunit project.
For more info, see here:
http://nunit.org/index.php?p=settingsDialog&r=2.5
In the past I've done this with a batch file running each assembly through the nunit console independently. At one point I had something that merged the xml output together. It might be in the CruiseControl.Net code.
I haven't worked on the NUnit project for a while. I only have the older code in my head. But the issue is that you get one config per AppDomain and NUnit loads all the test assemblies into one AppDomain.
You might want to try alternate runners such as Resharper or TestDriven.net