static async Task QueryStudents([NotNull] IExamSystem system, StudentDataRange range) => await Task.Run(() =>
{
for (long studentId = range.FromStudentId; studentId < range.ToStudentId; studentId += 1)
{
for (long courseId = range.FromCourseId; courseId < range.ToCourseId; courseId += 1)
{
system.Contains(studentId, courseId);
}
}
});
static Task RunOperation(Action <long, long> operation, StudentDataRange range)
{
return(Task.Run(() =>
{
for (long studentId = range.FromStudentId; studentId < range.ToStudentId; studentId += 1)
{
for (long courseId = range.FromCourseId; courseId < range.ToCourseId; courseId += 1)
{
operation(studentId, courseId);
}
}
}));
}
public void TestThatReadActionsAndWriteActionsNeverInterfere()
{
ILogger logger = new XmlLogger();
var system = NewExamSystem(logger);
var firstRange = new StudentDataRange(0, 100, 0, 10);
var secondRange = new StudentDataRange(100, 200, 0, 10);
var firstAdder = AddStudents(system, firstRange);
var secondAdder = AddStudents(system, secondRange);
var remover = RemoveStudents(system, firstRange);
var firstQuerier = QueryStudents(system, firstRange);
var secondQuerier = QueryStudents(system, secondRange);
var thirdQuerier = QueryStudents(system, firstRange);
var fourthQuerier = QueryStudents(system, secondRange);
var fifthQuerier = QueryStudents(system, firstRange);
var sixthQuerier = QueryStudents(system, secondRange);
firstAdder.Wait();
secondAdder.Wait();
remover.Wait();
firstQuerier.Wait();
secondQuerier.Wait();
thirdQuerier.Wait();
fourthQuerier.Wait();
fifthQuerier.Wait();
sixthQuerier.Wait();
try
{
// If resulting xml document is valid,
// the algorithm is very likely to be correct
// ReSharper disable once ReturnValueOfPureMethodIsNotUsed
XElement.Parse(logger.Log);
}
catch (Exception)
{
throw new FalseException("Could not parse log as xml", false);
}
}
public void TestConcurrentAddingWorksCorrectly()
{
var system = NewExamSystem();
var firstRange = new StudentDataRange(0, 1000, 0, 10);
var secondRange = new StudentDataRange(1000, 2000, 0, 10);
var thirdRange = new StudentDataRange(0, 1000, 10, 20);
var fourthRange = new StudentDataRange(1000, 2000, 10, 20);
var firstAdder = AddStudents(system, firstRange);
var secondAdder = AddStudents(system, secondRange);
var thirdAdder = AddStudents(system, thirdRange);
var fourthAdder = AddStudents(system, fourthRange);
firstAdder.Wait();
secondAdder.Wait();
thirdAdder.Wait();
fourthAdder.Wait();
var contents = system.Contents;
Assert.True(contents.Keys.Count == 2000);
Assert.True(contents.Values.SelectMany(it => it).Count() == 40000);
}