Configuring maximum number of tests has no effect in .NET Core

Here’s test pasted from https://fscheck.github.io/FsCheck/RunningTests.html

[Property]
public void Test()
{
	var configuration = Configuration.Quick;
	configuration.MaxNbOfTest = 1000;
	configuration.QuietOnSuccess = true;
	true.ToProperty().Check(configuration);	
}

I’m changing the number assigned to MaxNbOfTest and the flag to true/false, but the test runner always displays Ok, passed 100 tests. The application is targeting .NET Core 2.0:

<TargetFramework>netcoreapp2.0</TargetFramework>
//..
<PackageReference Include="xunit" Version="2.3.1" />
<PackageReference Include="xunit.runner.visualstudio" Version="2.3.1" />
<DotNetCliToolReference Include="dotnet-xunit" Version="2.3.1" />
<PackageReference Include="FsCheck" Version="2.10.6" />
<PackageReference Include="FsCheck.Xunit" Version="2.10.6" />

I was thinking runner itself has something to do with this, but both Resharper and Visual Studio Test Runner in my VS2017 provide same output.

[kurtschelfthout]

Like @ploeh said - that snippet is under the heading “Running a single property from an fsx/csx file or a command line runner”. What is happening is that you are running 100 times 1000 tests. The test method is interpreted as an Fscheck test with default config (there are properties on the PropertyAttribute to change these). Then, the inner test is true.ToProperty().Check which is executed 1000 times but doesn’t print anything on exit as per your config.

See here for xUnit.net examples: https://fscheck.github.io/FsCheck/RunningTests.html#Using-FsCheck-Xunit

EDIT: I noticed there are no C# examples there, here’s one that’s trivial and equivalent to the stand-alone snippet:

[Property(QuietOnSuccess = true, MaxNbOfTests=1000)]
public bool Test() => true

// this one will fail
[Property(QuietOnSuccess = true, MaxNbOfTests=1000)]
public bool Test(int i) => i > 0

[ploeh]

In a unit test, you either need QuickCheckThrowOnFailure as described in https://fscheck.github.io/FsCheck/RunningTests.html, or, if you’re using FsCheck.XUnit, you must return the Property.