Author: Pieter

In this example I will show how to create a Unit Test with TypeMock.

First I have created some basic dummy classes for the example

public sealed class ServiceFactory
{
    public static ExpireDateService CreateExpireDateService()
    {
        ExpireDateService expireDateService = new ExpireDateService();
        expireDateService.administration = new SqlAdministration("connectionstring");
        return expireDateService;
    }
}

/// <summary>
/// SqlAdministrion creates connection and managed queries with SQL
/// </summary>

public class SqlAdministration
{
    private static DateTime LoadParameterPrivate()
    {
        return DateTime.Parse("01-01-1980");

    }

    public SqlAdministration(string connectionString)
    {
        //Create connection to sql�
    }

    public static DateTime LoadParameter(string expireDateType)
    {
        //GET expireDate from Database:
         SqlAdministratie.LoadParameter("expireDateType");
        // Load Date from Private method for other mocking examples

        return LoadParameterPrivate();
    }
}

public class ExpireDateService
{
    public SqlAdministration administration;

    public DateTime GetDate(string expireDateType)
    {
        DateTime expireDate = SqlAdministration.LoadParameter(expireDateType);

        return expireDate;
    }
}

public class CheckDate
{
    public static bool CheckExpireDateBooking()
    {
        ExpireDateService expireDateService = ServiceFactory.CreateExpireDateService();
        DateTime expireDate = expireDateService.GetDate("expireDateDateFirst");
        return DateTime.Parse("01-01-2000") &lt; expireDate;
    }
}

With the following Unit test I will test the code written above. I don't want to change my code or add code for testing purpose. That's where Mocking comes in. With TypeMock I will mock the outcome of specified methods.

The first example is a standard unit test. No Mocking there.

[code language='c#']
///

/// Checks the expiredate from ‘database’ 01-01-1980
/// with a hardcoded date 01-01-2000
///

[TestMethod()]
public void TestMethodWithoutTypeMock()
{
    Assert.IsFalse(CheckDate.CheckExpireDateBooking());
} 

[/code]

 Now I want to mock the method GetDate to return a date specified by me (01-01-2010).

/// <summary>
/// Checks the expiredate from database (01-01-1980)
/// with a hardcoded date provided by TypeMock (01-01-2010)
/// </summary>

[Isolated]
[TestMethod()]
public void TestMethodWithTypeMockIsolate()
{
    //Create a dummy version of the ExpireDateService object to use for Mocking

    ExpireDateService expireDateService = new ExpireDateService();
    expireDateService.administration = new SqlAdministration("dummyConnectionString");

    //Return the declared expireDateService when method CreateExpireDateService is called

    Isolate.WhenCalled(() =&gt; ServiceFactory.CreateExpireDateService())
        .WillReturn(expireDateService);

    //Isolate the call to method expireDateService.GetDate with parameter 'expireDateDateFirst' and return 01-01-2010

    Isolate.WhenCalled(() =&gt; expireDateService.GetDate("expireDateDateFirst"))
        .WillReturn(DateTime.Parse("01-01-2010"));

    Assert.IsTrue(CheckDate.CheckExpireDateBooking());
}

For the latest example I wanted to Mock a Private method.

/// <summary>
/// Checks the expiredate from database (01-01-1980)
/// with a hardcoded date provided by TypeMock on privatemethod(01-01-2010)
/// </summary>

[Isolated]
[TestMethod()]
public void TestMethodWithTypeMockIsolatePrivate()
{
    Isolate.NonPublic.WhenCalled(typeof(SqlAdministration), "LoadParameterPrivate")
        .WillReturn(DateTime.Parse("01-01-2010"));

    Assert.IsTrue(CheckDate.CheckExpireDateBooking());
} 

You can download the source here:
MockingWithTypeMockExampleSource.zip (44.47 kb)

Hope it helps.

Cheers,

Pieter