5 Good Practices for Integration Testing with NUnit

by Joche Ojeda | Jan 2, 2023 | C#

Integration tests are a crucial part of any software development process, as they help ensure that different parts of a system are working together correctly. When writing integration tests, it is important to follow best practices in order to ensure that your tests are effective and maintainable. Here are a few good practices for integration testing using NUnit:

1. Use test fixtures: NUnit provides a concept called “test fixtures,” which allow you to set up and tear down common resources that are needed by multiple test cases. This can help reduce duplication and make your tests more maintainable.

   [TestFixture]
   public class DatabaseTests
   {
       private Database _database;
   
       [SetUp]
       public void SetUp()
       {
           _database = new Database();
       }
   
       [TearDown]
       public void TearDown()
       {
           _database.Dispose();
       }
   
       [Test]
       public void Test1()
       {
           // test code goes here
       }
   
       [Test]
       public void Test2()
       {
           // test code goes here
       }
   }
   

    

2. Use setup and teardown methods: In addition to test fixtures, NUnit also provides setup and teardown methods that can be used to perform common tasks before and after each test case. This can be helpful for setting up test data or cleaning up after a test.

   [TestFixture]
   public class DatabaseTests
   {
       private Database _database;
   
       [SetUp]
       public void SetUp()
       {
           _database = new Database();
       }
   
       [TearDown]
       public void TearDown()
       {
           _database.Dispose();
       }
   
       [SetUp]
       public void TestSetup()
       {
           // setup code goes here
       }
   
       [TearDown]
       public void TestTeardown()
       {
           // teardown code goes here
       }
   
       [Test]
       public void Test1()
       {
           // test code goes here
       }
   
       [Test]
       public void Test2()
       {
           // test code goes here
       }
   }
   

    

3. Use test cases: NUnit allows you to specify multiple test cases for a single test method using the TestCase attribute. This can help reduce duplication and make it easier to test different scenarios.

   [TestFixture]
   public class CalculatorTests
   {
       [TestCase(1, 2, 3)]
       [TestCase(10, 20, 30)]
       [TestCase(-1, -2, -3)]
       public void TestAdd(int x, int y, int expected)
       {
           Calculator calculator = new Calculator();
           int result = calculator.Add(x, y);
           Assert.AreEqual(expected, result);
       }
   }
   

    

4. Use the Assert class: NUnit provides a variety of assertions that can be used to verify the behavior of your code. It is important to use these assertions rather than manually checking for expected results, as they provide better error messages and make it easier to debug test failures.

   [TestFixture]
   public class CalculatorTests
   {
       [Test]
       public void TestAdd()
       {
           Calculator calculator = new Calculator();
           int result = calculator.Add(1, 2);
           Assert.AreEqual(3, result);
       }
   
       [Test]
       public void TestSubtract()
       {
           Calculator calculator = new Calculator();
           int result = calculator.Subtract(10, 5);
           Assert.AreEqual(5, result);
       }
   }
   

    

5. Use test categories: NUnit allows you to categorize your tests using the Category attribute. This can be helpful for organizing your tests and selectively running only certain categories of tests.

   [TestFixture]
   public class DatabaseTests
   {
       [Test]
       [Category("Database")]
       public void Test1()
       {
           // test code goes here
       }
   
       [Test]
       [Category("Database")]
       public void Test2()
       {
           // test code goes here
       }
   
       [Test]
       [Category("API")]
       public void Test3()
       {
           // test code goes here
       }
   }
      
   

    

By following these best practices, you can write integration tests that are effective, maintainable, and easy to understand. This will help you ensure that your code is working correctly and reduce the risk of regressions as you continue to develop and evolve your system.

Moving to apple silicon as a DotNet Developer

by Joche Ojeda | Dec 31, 2022 | C#

ARM (Advanced RISC Machine) is a popular architecture for mobile devices and other low-power devices. Microsoft has supported ARM architectures in the .NET framework for many years, and this support has continued with the release of .NET 6 and .NET 7.

In .NET 6 and 7, support for ARM architectures has been improved and expanded in several ways. One of the key changes is the introduction of ARM64 JIT (Just-In-Time) compilation, which allows .NET applications to take advantage of the performance improvements offered by the ARM64 architecture. This means that .NET applications can now be compiled and run natively on ARM64 devices, providing better performance and a more seamless experience for users.

Another important change in .NET 6 and 7 is the support for ARM32 and ARM64 for ASP.NET and ASP.NET Core. This means that developers can now build and deploy web applications on ARM devices, making it easier to create cross-platform applications that can run on a wide range of devices.

In addition to these changes, .NET 6 and 7 also include support for ARM64 in the .NET Native toolchain, which allows developers to build native applications for ARM devices using C# and .NET. This makes it easier to create high-performance, native applications for ARM devices without having to write code in a different language.

In conclusion, the support for ARM architectures in .NET 6 and 7 is an important development for developers who are looking to create and deploy applications on devices such as Apple’s M1 and M2. With this support, developers can take advantage of the performance and capabilities of the ARM architecture to create powerful and efficient applications that can run on a variety of devices. This will make it easier for developers to create and deploy applications on a wide range of devices, including mobile devices and other low-power devices. Overall, the support for ARM architectures in .NET 6 and 7 is a major improvement that will help developers create and deploy high-quality applications on a variety of devices.

How to wrap your synchronous implementation in an asynchronous implementation.

by Joche Ojeda | Dec 30, 2022 | C#

In this article, we will be discussing why it is sometimes useful to wrap your synchronous implementation in an asynchronous implementation.

Introduction

Async programming is an important paradigm in modern software development, allowing you to perform long-running tasks without blocking the calling thread. Async programming is particularly useful in scenarios where the operation may take a long time to complete, or when the operation is interacting with a slow resource, such as a network or a database.

One common scenario where you may need to wrap your synchronous implementation in an asynchronous implementation is when you are working with an API or a library that does not provide async versions of its methods. In these cases, you can use the Task.Run method to wrap the synchronous methods in a task, allowing you to use the await keyword to asynchronously wait for the operation to complete.

Example: Wrapping a Synchronous Data Processor

To illustrate this concept, let’s consider the following synchronous IDataProcessor interface:

public interface IDataProcessor
{
    void ProcessData(IEnumerable<IData> data);
}

This interface has a single method, ProcessData, which takes an IEnumerable of IData objects as input and processes the data.

Now let’s say that you want to use this IDataProcessor interface in an async context, but the interface does not provide an async version of the ProcessData method. To use this interface asynchronously, you can create an async wrapper class that wraps the synchronous implementation in an async implementation.

Here is an example of how you can wrap the synchronous IDataProcessor implementation in an asynchronous implementation:

public class AsyncDataProcessor : IDataProcessor
{
    private readonly IDataProcessor _dataProcessor;

    public AsyncDataProcessor(IDataProcessor dataProcessor)
    {
        _dataProcessor = dataProcessor;
    }

    public Task ProcessDataAsync(IEnumerable<IData> data)
    {
        return Task.Run(() => _dataProcessor.ProcessData(data));
    }
}

This implementation has a single method, ProcessDataAsync, which takes an IEnumerable of IData objects as input and asynchronously processes the data. The implementation uses the Task.Run method to wrap the synchronous ProcessData method in a task, allowing it to be called asynchronously using the await keyword.

To use this implementation, you can simply create an instance of AsyncDataProcessor and call the ProcessDataAsync method, passing in the list of data as an argument. For example:

var dataProcessor = new AsyncDataProcessor(new DataProcessor());
await dataProcessor.ProcessDataAsync(data);

Implementing asynchronous interfaces

by Joche Ojeda | Dec 30, 2022 | C#

In this article, we will be discussing how to define an async interface based on a synchronous interface example.

Introduction

Async interfaces are useful when you need to perform asynchronous operations within your application. Async interfaces allow you to define methods that return a Task object instead of a value, allowing you to use the await keyword to asynchronously wait for the operation to complete.

One important aspect of async programming is the ability to cancel an async operation. This is particularly useful in scenarios where the async operation may take a long time to complete, or when the operation is no longer needed. To support cancellation in async operations, you can use a cancellation token.

Step 1: Define the Synchronous Interface

The first step in defining an async interface is to define the synchronous version of the interface. This will serve as the basis for the async interface.

Here is an example of a synchronous interface:

public interface IDataProcessor
{
    void ProcessData(IEnumerable<IData> data);
}

This interface has a single method, ProcessData, which takes an IEnumerable of IData objects as input and processes the data.

Step 2: Define the Async Interface

Now that we have defined the synchronous interface, we can define the async version of the interface. To do this, we simply need to modify the ProcessData method to return a Task object instead of void, and add the async keyword to the method.

Here is the async version of the IDataProcessorAsync interface:

public interface IDataProcessorAsync
{
    Task ProcessDataAsync(IEnumerable<IData> data, CancellationToken cancellationToken);
}

In this version of the interface, we have added a cancellationToken parameter to the ProcessDataAsync method. This parameter is of type CancellationToken, which is a struct that represents a cancellation request.

Step 3: Implement the Async Interface

Now that we have defined the async version of the interface, we can implement it in a class. To implement the async interface, we simply need to define a method that matches the signature of the ProcessDataAsync method and uses the await keyword to asynchronously perform the data processing.

Here is an example of an async implementation of the IDataProcessorAsync interface:

public class DataProcessor : IDataProcessorAsync
{
    public async Task ProcessDataAsync(IEnumerable<IData> data, CancellationToken cancellationToken)
    {
        // Process the data asynchronously
        await Task.Delay(1000, cancellationToken);
    }
}

This implementation has a single method, ProcessDataAsync, which takes an IEnumerable of IData objects and a cancellationToken as input and asynchronously processes the data. In this example, the data processing is simulated using the Task.Delay method, which causes the task to wait for a specified amount of time before completing. The cancellationToken is passed to the Task.Delay method as an argument, allowing the task to be cancelled if a cancellation request is made.

Step 4: Use the Async Interface

Now that we have defined and implemented the async interface, we can use it in our application. To use the async interface, we simply need to create an instance of the implementing class and call the async method using the await keyword.

Here is an example of how to use the async IDataProcessor interface:

var cts = new CancellationTokenSource();
var dataProcessor = new DataProcessor();
await dataProcessor.ProcessDataAsync(data, cts.Token);

This code creates a CancellationTokenSource object, which is used to create and manage a cancellation token. The cts.Token property is then passed to the ProcessDataAsync method as a cancellation token. The await keyword is used to asynchronously wait for the data processing to complete.

To cancel the async operation, you can call the Cancel method on the CancellationTokenSource object. This will trigger a cancellation request, which will cause the ProcessDataAsync method to throw a TaskCanceledException when the await keyword is encountered.

cts.Cancel();

Conclusion

In this article, we discussed how to define an async interface based on a synchronous interface example, including the use of a cancellation token. We defined the synchronous version of the interface, modified it to include a cancellation token and return a Task object, implemented the async interface in a class, and demonstrated how to use your new async interface implementation.