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mock - testing if a method is called without specifying arguments

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This would be a correct rebinding:

from django.core
import mail
mail.send_mail = Mock()

but it's easier to use the patch() context manager / decorator:

with patch('django.core.mail.send_mail') as mocked_send_mail:
   # run your tests
self.assertTrue(mocked_send_mail.called)

Suggestion : 2

Mock Testing If A Method Is Called Without Specifying Arguments,I get an error, as the called attribute is still False. How can I test if a method has been called without having to specify attributes. , If you want to test that a certain method was called (or in some instances NOT called) you will need to use a mocking library. When writing C#, Moq is a great tool. Moq provides a method called Verify () that will allow you to test if a mocked object has been used in an expected way. , Mock testing is an approach to unit testing that lets you make assertions about how the code under test is interacting with other system modules. In mock testing, the dependencies are replaced with objects that simulate the behaviour of the real ones. 


from django.core.mail
import send_mail send_mail = Mock()

from django.core
import mail mail.send_mail = Mock()
from django.core.mail
import send_mail send_mail = Mock()
self.assertEqual(send_mail.called, True)
from django.core
import mail mail.send_mail = Mock()
with patch('django.core.mail.send_mail') as mocked_send_mail: # run your testsself.assertTrue(mocked_send_mail.called)

Suggestion : 3

Mock - testing if a method is called without specifying arguments,Should a modifying class method save itself or be explicity called after the method is called?,How to mock patch the Serializer.is_valid() method when unit testing in Django Rest Framework,How can I run some code when a Django model’s save method is called for the first time?

This would be a correct rebinding:

from django.core
import mail
mail.send_mail = Mock()

but it's easier to use the patch() context manager / decorator:

with patch('django.core.mail.send_mail') as mocked_send_mail:
   # run your tests
self.assertTrue(mocked_send_mail.called)

Suggestion : 4

In this tutorial, we have written several unit tests using Mockito for both stubbing and mocking.,Semaphore also provides tutorials for mocking in other languages if your interests go beyond Java:,The theory behind mocking and stubbing is so vast that it would need an entire book on its own. This tutorial will summarize the basics of it.,Once you’ve mastered writing unit tests with JUnit and Mockito, the next step is to set up Continuous Integration (CI) to automate testing.

Mockito is already distributed via Maven central, so using it in a Java forward is a painless process. We need to modify the pom.xml: 

    <dependencies>
       <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.12</version>
          <scope>test</scope>
       </dependency>
       <dependency>
          <groupId>org.mockito</groupId>
          <artifactId>mockito-core</artifactId>
          <version>3.2.4</version>
          <scope>test</scope>
       </dependency>
    </dependencies>

Here is the code for the customer: 

    @Entity
    public class Customer {

       @Id
       @GeneratedValue(strategy = GenerationType.AUTO)
       private long id;

       private String firstName;

       private String lastName;

       //...getters and setters redacted for brevity...

    }

and here is our business class: 

	public class CustomerReader {

	   @PersistenceContext
	   private EntityManager entityManager;

	   public String findFullName(Long customerID) {
	      Customer customer = entityManager.find(Customer.class, customerID);
	      return customer.getFirstName() + " " + customer.getLastName();
	   }

	}

You might have already noticed that our CustomerReader class is not correct, as it does not handle the null case, i.e. the given database ID does not exist as an object in the DB. While we could copy-paste the existing unit test, it is best if we organize the code with a common test method. 

	public class CustomerReaderTest {

	   //Class to be tested
	   private CustomerReader customerReader;

	   //Dependencies
	   private EntityManager entityManager;

	   @Before
	   public void setup() {
	      customerReader = new CustomerReader();

	      entityManager = mock(EntityManager.class);
	      customerReader.setEntityManager(entityManager);
	   }

	   @Test
	   public void happyPathScenario() {
	      Customer sampleCustomer = new Customer();
	      sampleCustomer.setFirstName("Susan");
	      sampleCustomer.setLastName("Ivanova");

	      when(entityManager.find(Customer.class, 1 L)).thenReturn(sampleCustomer);

	      String fullName = customerReader.findFullName(1 L);
	      assertEquals("Susan Ivanova", fullName);
	   }

	   @Test
	   public void customerNotPresentInDb() {
	      when(entityManager.find(Customer.class, 1 L)).thenReturn(null);

	      String fullName = customerReader.findFullName(1 L);
	      assertEquals("", fullName);
	   }
	}

Let’s see a case where a mock is needed instead of a stub, assuming that we want to test the following class in the same application: 

	public class LateInvoiceNotifier {

	   private final EmailSender emailSender;
	   private final InvoiceStorage invoiceStorage;

	   public LateInvoiceNotifier(final EmailSender emailSender, final InvoiceStorage invoiceStorage) {
	      this.emailSender = emailSender;
	      this.invoiceStorage = invoiceStorage;
	   }

	   public void notifyIfLate(Customer customer) {
	      if (invoiceStorage.hasOutstandingInvoice(customer)) {
	         emailSender.sendEmail(customer);
	      }
	   }
	}

Suggestion : 5

This matcher specifies that when the HasInventory method is called with any string as a first argument and any int as a second it should return true.,Matchers let you ignore passing actual values as arguments used in mocks. Instead, they give you the possibility to pass just an expression that satisfies the argument type or the expected value range. For example, if a method accepts a string as a first parameter, you don’t need to pass a specific string like "Camera". Instead, you can use Arg.IsAny(). ,Matchers also let you ignore all arguments in your mocks by a single call to IgnoreArguments() (in the arrangement) or Args.Ignore() (in the assertion).,You already saw how you can use matchers in your assertion calls. If you need you can specify that you want to ignore all arguments in the assert call. You do this by adding the Args.Ignore() argument to the Mock.Assert call. Here is an example:

1._
public interface IFoo {
   int Echo(int intArg1);
   int Echo(int intArg1, int intArg2);
   int Bar(ref int intArg1);
}
public interface IFoo 
{ 
    int Echo(int intArg1); 
    int Echo(int intArg1, int intArg2); 
    int Bar(ref int intArg1); 
} 

Public Interface IFoo
Function Echo(ByVal int As Integer) As Integer
Function Echo(ByVal int1 As Integer, ByVal int As Integer) As Integer
Function Bar(ByRef int1 As Integer) As Integer
End Interface
1._
public interface IPaymentService {
   void ProcessPayment(DateTime dateTi, decimal deci);
}
public interface IPaymentService 
{ 
    void ProcessPayment(DateTime dateTi, decimal deci); 
} 

Public Interface IPaymentService
Sub ProcessPayment(ByVal dateTi As DateTime, ByVal deci As Decimal)
End Interface
1._
Mock.Arrange(() => warehouse.HasInventory(Arg.IsAny<string>(), Arg.IsAny<int>())).Returns(true);
Mock.Arrange(() => warehouse.HasInventory(Arg.IsAny<string>(), Arg.IsAny<int>())).Returns(true); 

Mock.Arrange(Function() warehouse.HasInventory(Arg.IsAny(Of String)(), Arg.IsAny(Of Integer)())).Returns(True)
1._
Mock.Arrange(() => foo.Echo(Arg.IsInRange(0, 5, RangeKind.Inclusive))).Returns(true);
Mock.Arrange(() => foo.Echo(Arg.IsInRange(0, 5, RangeKind.Inclusive))).Returns(true); 

Mock.Arrange(Function() foo.Echo(Arg.IsInRange(0, 5, RangeKind.Inclusive))).Returns(True)
1._
Mock.Arrange(() => foo.Echo(Arg.IsInRange(0, 5, RangeKind.Exclusive))).Returns(true);
Mock.Arrange(() => foo.Echo(Arg.IsInRange(0, 5, RangeKind.Exclusive))).Returns(true); 

Mock.Arrange(Function() foo.Echo(Arg.IsInRange(0, 5, RangeKind.Exclusive))).Returns(True)
1._
Mock.Arrange(() => foo.Echo(Arg.Matches<int>( x => x < 10)).Returns(true);
Mock.Arrange(() => foo.Echo(Arg.Matches<int>( x => x < 10)).Returns(true); 

Mock.Arrange(Function() foo.Echo(Arg.Matches(Of Integer)(Function(x) x < 10))).Returns(True)


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