anchor.diff:                let succeeded = runTests asm
                 if not succeeded then yield asm ]
   
  -    if not (List.isEmpty failedTests)
  -    then failwithf "xUnit failed for the following assemblies: %s" (separated ", " failedTests)
  +    if not (List.isEmpty failedTests) then
  +        sprintf "xUnit failed for the following assemblies: %s" (separated ", " failedTests)
  +        |> match parameters.ErrorLevel with
  +           | Error -> failwith
  +           | DontFailBuild -> traceImportant
   
       traceEndTask "xUnit" details
positive.code:       /// If the timeout is reached the xUnit task will be killed. Default is 5 minutes.
        TimeOut: TimeSpan
        /// The output directory. It's the current directoy if nothing else is specified.
        OutputDir: string }
  
  /// The xUnit default parameters
  let XUnitDefaults =
  
negative.code:       Verbose = true;
        XmlOutput = false;
        TimeOut = TimeSpan.FromMinutes 5.
        OutputDir = null
        ErrorLevel = Error }
  
  /// Runs xUnit unit tests in the given assemblies via the given xUnit runner.
  /// Will fail if the runner terminates with non-zero exit code for any of the assemblies.
  