Should the CustomEventArgs method implement another Interface? - unit-testing

Hi I am using test driven development and seem to be in an area I am not familiar. Could you Please check and let me know what changes I should make in my code to make it "unit testable" ?
Code to be tested:
public void PurchaseItemList()
{
//call methods to checkavailablility
If(!productAvailable)
{
purchaseItemEventArgs.IsSuccessfull = false;
}
else
{
purchaseItemEventArgs.IsSuccessfull = true;
// code to update model.
purchaseItemEventArgs.ItemsPurchased = GetItemsPurchased()
}
}
Now the issue I face is that I cannot mock the purchaseItemEventArgs class as it does not implement any interface. I am using moq for testing. Any advise on the code changes to make it unit testable would be very helpfull.
Thanks

Since GetItemsPurchased() is a method of your class, you could make it protected virtual. So you could then define a test class like this:
class TestableMyClass : MyClass{
private Items _items;
public TestableMyClass(Items items) : base() {
_items = items;
}
protected Items GetItemsPurchased(){
return _items;
}
}
And then, in your tests, replace new MyClass by new TestableMyClass(myItems).
This way, your actual GetItemsPurchased() won't be called in your tests, and you can inject the items you want.

Related

Is there a better solution to test getters with the Google Test Framework

I am testing the getters of a class. Each getter has some regex code to validate the input.
I use the Google Test Framework to write the unit tests.
Every time I want to test a new getter I need to expand the parameters of the constructor. I need to update the code of the previous tests to not break the previous tests.
Like this:
TEST_F(wsRecordTest,DoesItThrowExceptionWhenWrongCitynameIsProvided)
{
weatherdayRecord wsRecord{"!#Delft$*"}; --> has to be: weatherdayRecord wsRecord{"!#Delft$*","2020-10-03"};
ASSERT_THROW(wsRecord.getCity(),std::invalid_argument);
}
// Test accessor getDate() and constructor
TEST_F(wsRecordTest,DoIGetTheRightDateFromTheConstructor)
{
weatherdayRecord wsRecord{"Delft","2020-10-03"};
ASSERT_EQ(wsRecord.getDate(),"2020-10-03");
}
Is there a way to avoid this?
How about adding a SetUp functionality to your fixture?
class wsRecordTest : public ::testing::Test {
protected:
std::unique_ptr<weatherdayRecord> record;
void SetUp() override {
record = std::make_unique<weatherdayRecord>("Delft", "2020-10-03");
}
}
TEST_F(wsRecotdTest, CheckDate) {
ASSERT_EQ(record->getDate(), "2020-10-03");
}
Not sure though why you want to test your getters if the classes are just holders for data..

Create a Partial Stub in Microsoft Moles

I am pulling my hair out with this one. I have looked and cannot find a simple, clear example of creating and using a partial stub with Microsoft Moles. Maybe I'm missing somethimg, or have my code architected poorly, but I can't seem to get this to work.
Here's my class (simplified):
public class AccountService : IAccountService {
private readonly webServiceProxy IExternalWebServiceProxy;
public AccountService(IExternalWebServiceProxy webServiceProxy) {
this.webServiceProxy = webServiceProxy;
}
public List<AccountModel> GetAccounts(string customerId) {
var returnList = new List<AccountModel>();
var xmlResponse = webServiceProxy.GetAllCustomerAccounts(customerId);
var accountNodes = xmlResponse.SelectNodes("//AccountNodes");
if (accountNodes != null)
{
foreach (XmlNode node in accountNodes)
{
var account = this.MapAccountFromXml(node);
if (!string.IsNullOrEmpty(account.AccountNumber))
{
returnList.Add(account);
}
}
}
return returnList;
}
public AccountModel MapAccountFromXml(XmlNode node) {
if (!IsValidAccount(node) {
return null;
}
// This performs a lot of XML manipulation getting nodes based on attributes
// and mapping them to the various properties of the AccountModel. It's messy
// and I didn't want it inline with the other code.
return populatedAccountModel;
{
public bool IsValidAccount(XmlNode node)
{
var taxSelectValue = node.SelectSingleNode("//FORMAT/Field[#taxSelect='1']").First().Value;
var accountStatus = // similar to first line in that it gets a single node using a specific XPath
var maturityDate = // similar to first line in that it gets a single node using a specific XPath
var maturityValue = // similar to first line in that it gets a single node using a specific XPath
return taxSelectValue != string.Empty && taxSelectValue != "0" && (accountStatusValue != "CL" || (maturityDate.Year >= DateTime.Now.AddYears(-1).Year));
}
}
What I want to do is test my GetAccounts() method. I can stub out the IExternalWebServiceProxy call and return fake XML, but I have internal calls happening in my service since my GetAccounts() method calls MapAccountFromXml() which in turn calls IsValidAccount().
Perhaps the solution is to not worry about breaking out the long and involved MapAccountFromXml() and IsValidAccount() code and just put them inline into the GetAccount() call, but I would rather leave them broken out for code readability.
I have my Moles assembly created, and know I can create a stub version of my class like this
var stubWebService = SIExternalWebServiceProxy {
GetAllCustomerAccounts = delegate {
return SomeHelper.GetFakeXmlDocument();
}
}
var stubAccountService = new SAccountService() { callsBase = true; }
My problem is I don't know how to then override the internal calls to MapAccountFromXml and IsValidAccount and I don't want my Unit Test to be testing thos methods, I'd like to isolate GetAccounts for the test. I read somewhere the methods need to be virtual to be overriden in a partial stub, but could not find anything that then showed how to create a stub that overrides a few methods while calling the base for the one I want to test.
Peer put me on the right track, thank you.
It turned out that what I was looking for is called Detours in Moles. Rather than stub an interface using
var stubAccountService = new SIAccountService();
what I needed to do was create an instance of my AccountService and then detour all calls to the methods I wanted to mock, like this
var accountService = new AccountService();
MAccountService.AllInstances.MapAccountFromXmlXmlNode = delegate {
return new AccountModel();
};
The MAccountService is provided by Moles when you Mole your assembly. The only missing piece to this is that for this to work you need to add the following attribute to your test method:
[HostType("Moles")]
This worked for me locally, but in the end I had trouble getting TFS to do automated builds
UPDATE
I just stumbled on another way of doing this, while looking at Rhino Mocks. If the methods in the class being mocked are virtual then you can override them in the mock, like this:
var accountService = new SAccountService();
accountService.MapAccountFromXmlXmlNode = delegate
{
return new AccountModel();
}
Now I can call
accountService.GetMemberAccounts();
and when accountService makes its call to MapAccountFromXml it will be caught by the stub and processed as I deem necessary. No messing with HostType and it works like a charm.
To test methods in you class in issolation you do this with moles by making a mole for the IsValidAccount and MapAccountFromXml methods. Or make a stub implementation with stubs where you let the stub call the orriginal methode using base. Or what I think is a nicer solution, make a test class which overrides the methods you do want to stub (this is the same what a stub would do, except you see all what is happening in your own code):
public class TestHelperAccountService : AccountService {
public override AccountModel MapAccountFromXml(XmlNode node) {
return new AccountModel(){
//Accountmodelstub
};
{
public override bool IsValidAccount(XmlNode node)
{
return true;
}
}
This way you can do your test for the GetAccount method on your TestHelperAccountService class where you GetAccount method runs in full issolation. You can do the same for the methods like MapAccountFromXml to test them seperatly.

mocking a method while calling a method in same service class groovy grails

im looking for something similar to what i would do with rhino mocks but in groovy.
i sometimes use partial mocks as well.
in ASP -- Rhino mocks
const string criteria = "somecriteriahere";
ISomeRepository mockSomeRepository = MockRepository.GenerateStrictMock<SomeRepository>();
mockSomeRepository.Expect(m => m.GetSomesByNumber(criteria)).Return(new List<Some>() { });
mockSomeRepository.Expect(m => m.GetSomesByName(criteria)).Return(new List<Some>() { });
mockSomeRepository.Expect(m => m.GetSomesByOtherName(criteria)).Return(new List<Some>() { });
mockSomeRepository.SearchForSomes(criteria);
mockSomeRepository.VerifyAllExpectations();
--------note the virtual -------
public class SomeRepository : ISomeRepository {
public virtual IEnumerable<Some> GetSomesByNumber(string num)
{
//some code here
}
public virtual IEnumerable<Some> GetSomesByName(string name)
{
//some code here
}
public virtual IEnumerable<Some> GetSomesByOtherName(string name)
{
//some code here
}
public IEnumerable<Some> SearchForSomes(string criteria) {
this.GetSomesByNumber(criteria); //tested fully seperatly
this.GetSomesByName(criteria); //tested fully seperatly
this.GetSomesByOtherName(criteria); //tested fully seperatly
//other code to be tested
}
}
GetSomesByNumber, GetSomesByName, GetSomesByOtherName would be tested fully seperatly. If i actually provided values and went into those functions, to me, that seems like in integration test where im testing multiple functionalities and not one unit of work.
So, SearchForSomes i would only be testing that method and mocking away all other dependencies.
In Grails
class XService {
def A() {
}
def B() {
def result = this.A()
//do some other magic with result
}
}
I have tried this -- but failed
def XServiceControl = mockFor(XService)
XServiceControl.demand.A(1..1) { -> return "aaa" }
// Initialise the service and test the target method.
//def service = XServiceControl.createMock();
//def service = XServiceControl.proxyInstance()
// Act
//def result = XServiceControl.B(_params);
XServiceControl.use {
new XService().B(_params)
}
Ive got no idea how to do this, does any one know how?
Thanks
If you're using groovy MockFor (e.g. groovy.mock.interceptor.MockFor), then you need to enclode the usage in a .use{} block.
However, it looks like you are calling mockFor from within a grails.test.GrailsUnitTestCase. In that case, there's no need for the .use{} block: the scope of the mock is the whole test.
thanks for your reply ataylor
seem what i was trying to accomplish is something called partial/half mocking. Here are some links.
http://www.gitshah.com/2010/05/how-to-partially-mock-class-and-its.html
http://mbrainspace.blogspot.com/2010/02/partial-half-mocks-why-theyre-good-real.html
https://issues.apache.org/jira/browse/GROOVY-2630
https://issues.apache.org/jira/browse/GROOVY-1823
http://java.dzone.com/articles/new-groovy-171-constructor
I didnt accomplish this, i ended up extracting B() into its own class and injecting a mock of XService into B's class -- Dependency Injection. I was also informed that extracting away dependencies is a better practice for testing. So, i am now very carefull when using this.() :D

Unit Testing abstract classes and or interfaces

I'm trying to start using Unit Testing on my current project in Visual Studio 2010. My class structure, however, contains a number of interface and abstract class inheritance relationships.
If two classes are derived from the same abstract class, or interface I'd like to be able to share the testing code between them. I'm not sure how to do this exactly. I'm thinking I create a test class for each interface I want to test, but I'm not sure the correct way to feed my concrete classes into the applicable unit tests.
Update
OK here's an example. Say I have an interface IEmployee , which is implemented by an abstract class Employee, which is then inherited by the two concrete classes Worker and Employee. (Code show below)
Now say I want to create tests that apply to all IEmployees or Employees. Or alternatively create specific tests for specific types of Employees. For example I may want to assert that setting IEmployee.Number to a number less then zero for any implementation of IEmployee throws an exception. I'd prefer to write the tests from the perspective of any IEmployee and then be able to use the tests on any implementation of IEmployee.
Here's another example. I may also want to assert that setting the vacation time for any employee to a value less then zero throws and error. Yet I may also want to have different tests that apply to a specific concrete version of Employee. Say I want to test that Worker throws an exception if they are provided more then 14 days vacation, but a manager can be provided up to 36.
public interface IEmployee
{
string Name {get; set;}
int Number {get; set;}
}
public abstract class Employee:IEmploee
{
string Name {get; set;}
int Number {get;set;}
public abstract int VacationTime(get; set;)
}
public abstract class Worker:IEmployee
{
private int v;
private int vTime;
public abstract int VacationTime
{
get
{
return VTime;
}
set
{
if(value>36) throw new ArgumentException("Exceeded allowed vaction");
if(value<0)throw new ArgumentException("Vacation time must be >0");
vTime= value;
}
}
public void DoSomWork()
{
//Work
}
}
public abstract class Manager:IEmployee
{
public abstract int VacationTime
{
get
{
return VTime;
}
set
{
if(value>14) throw new ArgumentException("Exceeded allowed vaction");
if(value<0)throw new ArgumentException("Vacation time must be >0");
vTime= value;
}
}
public void DoSomeManaging()
{
//manage
}
}
So I guess what I'm looking for is a work flow that will allow me to nest unit tests. So for example when I test the Manager class I want to first test that it passes the Employee and IEmployee tests, and then test specific members such as DoSomeManaging().
I guess I know what you mean. I had the same issue.
My solution was to create a hierarchy also for testing. I'll use the same example you show.
First, have an abstract test class for the base IEmployee.
It has two main things:
i. All the test methods you want.
ii. An abstract method that returns the desired instance of the IEmployee.
[TestClass()]
public abstract class IEmployeeTests
{
protected abstract GetIEmployeeInstance();
[TestMethod()]
public void TestMethod1()
{
IEmployee target = GetIEmployeeInstance();
// do your IEmployee test here
}
}
Second, you have a test class for each implementation of IEmployee, implementing the abstract method and providing appropriate instances of IEmployee.
[TestClass()]
public class WorkerTests : IEmployeeTests
{
protected override GetIEmployeeInstance()
{
return new Worker();
}
}
[TestClass()]
public class ManagerTests : IEmployeeTests
{
protected override GetIEmployeeInstance()
{
return new Manager();
}
}
You can see everything works as expected and VS gives you the expected test methods for each WorkerTests and ManagerTests classes in the TestView window.
You can run them and have the test results for each implementation of the IEmployee interface, having to create the tests only in the base IEmployeeTests class.
You can always add specific test for the derived WorkerTests and ManagerTests classes.
The question would be now, what about classes that implement multiple interfaces, let's say EmployedProgrammer?
public EmployedProgrammer : IEmployee, IProgrammer
{
}
We don't have multiple inheritance in C#, so this is not an option:
[TestClass()]
public EmployedProgrammerIEmployeeTests : IEmployeeTests, IProgrammerTests
{
// this doesn't compile as IEmployeeTests, IProgrammerTests are classes, not interfaces
}
For this scenario, a solution is to have the following test classes:
[TestClass()]
public EmployedProgrammerIEmployeeTests : IEmployeeTests
{
protected override GetIEmployeeInstance()
{
return new EmployedProgrammer();
}
}
[TestClass()]
public EmployedProgrammerIProgrammerTests : IProgrammerTests
{
protected override GetIProgrammerInstance()
{
return new EmployedProgrammer();
}
}
with
[TestClass()]
public abstract class IProgrammerTests
{
protected abstract GetIProgrammerInstance();
[TestMethod()]
public void TestMethod1()
{
IProgrammer target = GetIProgrammerInstance();
// do your IProgrammerTest test here
}
}
I'm using this with good results.
Hope it helps.
Regards,
Jose
What I think you want to do is create unit tests for methods in abstract classes.
I'm not sure it makes sense to want to test a protected method on an abstract class, but if you insist simply extend the class in a class used exclusively for unittesting. That way you can expose the protected methods on the abstract class you want to test through public methods on the extending class that simply call through to the method on the abstract class.
If you have methods in abstract classes that you want unittested, I suggest refactoring them into separate classes and simply expose them as public methods and put those under test. Try looking at your inheritance tree from a 'test-first' perspective and I'm pretty sure you'll come up with that solution (or a similar one) as well.
It seems that you have described "composite unit testing" which is not supported by Visual Studio 2010 unit tests. Such things can be done in MbUnit according to this article. It is possible to create abstract tests in Visual Studio 2010 which is probably not exactly what you want. Here is description how to implement abstract tests in VS (Inheritance Example section).
Use microsoft moles for better testing. so you can mock the abstract base class / static methods etc easily. Please refer the following post for more info
detouring-abstract-base-classes-using-moles
BenzCar benzCar = new BenzCar();
new MCar(benzCar)
{
Drive= () => "Testing"
}.InstanceBehavior = MoleBehaviors.Fallthrough;
var hello = child.Drive();
Assert.AreEqual("Benz Car driving. Testing", hello);
The desire to run the same test against multiple classes usually means you have an opportunity to extract the behavior you want to test into a single class (whether it's the base class or an entirely new class you compose into your existing classes).
Consider your example: instead of implementing vacation limits in Worker and Manager, add a new member variable to Employee, 'MaximumVacationDays', implement the limit in the employee class' setter, and check the limit there:
abstract class Employee {
private int maximumVacationDays;
protected Employee(int maximumVacationDays) {
this.maximumVacationDays = maximumVacationDays
}
public int VacationDays {
set {
if (value > maximumVacationDays)
throw new ArgumentException("Exceeded maximum vacation");
}
}
}
class Worker: Employee {
public Worker(): Employee(14) {}
}
class Manager: Employee {
public Manager(): Employee(36) {}
}
Now you have only one method to test and less code to maintain.

Unit test complex classes with many private methods

I've got a class with one public method and many private methods which are run depending on what parameter are passed to the public method so my code looks something like:
public class SomeComplexClass
{
IRepository _repository;
public SomeComplexClass()
this(new Repository())
{
}
public SomeComplexClass(IRepository repository)
{
_repository = repository;
}
public List<int> SomeComplexCalcualation(int option)
{
var list = new List<int>();
if (option == 1)
list = CalculateOptionOne();
else if (option == 2)
list = CalculateOptionTwo();
else if (option == 3)
list = CalculateOptionThree();
else if (option == 4)
list = CalculateOptionFour();
else if (option == 5)
list = CalculateOptionFive();
return list;
}
private List<int> CalculateOptionOne()
{
// Some calculation
}
private List<int> CalculateOptionTwo()
{
// Some calculation
}
private List<int> CalculateOptionThree()
{
// Some calculation
}
private List<int> CalculateOptionFour()
{
// Some calculation
}
private List<int> CalculateOptionFive()
{
// Some calculation
}
}
I've thought of a few ways to test this class but all of them seem overly complex or expose the methods more than I would like. The options so far are:
Set all the private methods to internal and use [assembly: InternalsVisibleTo()]
Separate out all the private methods into a separate class and create an interface.
Make all the methods virtual and in my tests create a new class that inherits from this class and override the methods.
Are there any other options for testing the above class that would be better that what I've listed?
If you would pick one of the ones I've listed can you explain why?
Thanks
You don't need to change your interface to test these methods. Simply test the public interface thoroughly to ensure that all the private methods are tested:
void Test1()
{
new SomeComplexClass(foo).SomeComplexCalcualation(1);
}
void Test2()
{
new SomeComplexClass(foo).SomeComplexCalcualation(2);
}
and so on...
You can use a coverage tool (e.g. NCover for .NET) to ensure that all the code you wanted to test has actually been tested.
How about OptionCalculators, to which the original class dispatches the work? Each would have just one method, CalculateOption, and of course it would be public, and therefore readily testable.
You should only need to test the public methods of the Class/Interface.
You just need to be sure you have enough Unit test cases to thoroughly test all the different behaviors of those public methods (which would excersise the private methods appropriately).
If each of those computations is that complex, is each one really a single method? If those computations share code, or should be multiple methods each, it's an argument for the interface/Strategy approach you mention, so you can test each of those steps.
Another thing to consider: thoroughly exercising the one public method is testing two things
a) that the ComputeOptionN code is working, AND
b) that the option checking is working properly.
Not a problem if you're literally passing in ints, but not ideal, especially if the comparison could ever get more complicated, or if it might change around.
#Carl is right. This is nothing more than utilizing a strategy pattern. Store all the calculators in an array inject the array into SomeComplexClass. This will allow you to unit test each calculator by itself and the SomeComplexClass. Now you can do this:
public List<int> SomeComplexCalcualation(int option)
{
return calculator.find(option);
}
Very easy to mock calculator