Using NUnit tests is about testing different aspects of your application. So that as you make changes and add features you don't break anything. But it can be hard to get started with unit testing. Sometimes we are in too much of a rush to add testing to our applications if we don't take the time to add it in at the start but it doesn't have to be.

In this post I'm going to cover building some small real world tests to test parts of an application. It only takes 5 / 10 mins to do this.

Cloudstatus.eu is a web application I created for monitoring Cloud infrastructure we use to build services. It monitors Azure, AWS, Google Cloud, Github and more and sends alerts to your inbox or slack and more places.

To keep everything clean I've created a sample application that is a smaller version of Cloudstatus.eu and added some tests to it.

You can get the source here

If you are looking for how to add NUnit check out my blog post Your first NUnit Test

The Setup

• NUnit_Demo.Web
• Nunit_Demo.Data
• Nunit_Demo.Tests

Nunit_Demo.Web is the MVC application.

NunitDemo.Data is a class library that get's called by the HomeController in the NunitDemo.Web application. This returns a list of providers.

Nunit_Demo.Tests is where the tests take place and run from.

In Nunit_Demo.Data we have a class ProviderQueries

    public List<Provider> GetProviders()
    {
        List<Provider> _records = new List<Provider>();

        _records.Add(AddProvider(1, "Azure", "Windows Azure", "All Ok", "Running Fine"));
        _records.Add(AddProvider(2, "AWS", "Amazon Web Services", "All Ok", "Running Fine"));


        return _records;
    }


    // This method will throw an expection to see the test failing.
    public List<Provider> GetProvidersNoDatabase()
    {
        List<Provider> _records = new List<Provider>();


        throw  new Exception("database missing");

        return _records;
    }

    public Provider AddProvider(int Id, string ProviderCode, string ProviderName, string Title, string Status)
    {
        Provider _record = new Provider
        {
            Id = Id,
            Provider_Code_CH = ProviderCode,
            Provider_Name_VC = ProviderName,
            Current_Title_VC = Title,
            Current_Status_VC = Status,
            Updated_DT = DateTime.Now,
            Display_Date = DateTime.Now.ToString(DateFormat),
            Preview_BT = false
        };

        return _record;
    }
}

I won't cover this in detail but we have a method GetProviders which will add some providers and return the list.

We also have a method called GetProvidersNoDatabase that will throw an Exception.

If you read my last post you'll know I like to watch tests break first just for fun.

The Tests

Ok lets create some tests. I did promise these are quick short tests you can add to any application.

In Nunit_Demo.Tests

Add the nuget packages for Nunit and Nunit test adapter.

We create a class "ProviderTests"

[TestFixture]
class ProviderTest

We add [TestFixture] and create our first method as below.

    [Test]
    public void LoadProviders()
    {
        List<Provider> _providers = new List<Provider>();

        Boolean bResult = true;
        string sStatusMessage = "";
        ProviderQueries PQ = new ProviderQueries();

        _providers = PQ.GetProviders();

        if (_providers.Count != 0)
        {
            bResult = true;
            sStatusMessage = "Yes has providers";
        }
        else
        {
            bResult = false;
            sStatusMessage = "No Providers";
        }

        Assert.IsTrue(bResult, sStatusMessage);
    }

This test calls the ProviderQueries class in the Nunit_Demo.Data class library.

_providers = PQ.GetProviders() will call the method and load the providers list.

if (_providers.Count != 0)

We then check the count for the list. If there are 0 records we know the test failed. This application should always have something.

Assert.IsTrue(bResult, sStatusMessage);

Assert is the basic Pass / fail for nunit tests. bResult is set to true or false depending on the number of records we have.

That's it, in under 20 lines of code we have a testr that will check if our application gets the providers back and we can move on.

Another way to do it

    [Test]
    public void LoadProviderNoDatabases()
    {
        List<Provider> _providers = new List<Provider>();

        ProviderQueries PQ = new ProviderQueries();

        _providers = PQ.GetProvidersNoDatabase();

        if (_providers.Count != 0)
        {
            Boolean bResult = true;

            Assert.IsTrue(bResult, "Providers loaded");
        }
        else
        {
            Assert.IsFalse(false, "No Providers loaded");
        }
    }

ProviderQueries also has a method that will always fail. So we have added that in here as a test.

Open test Explorer and run all we have 3 tests on our sample application our first test from the last post on getting started.

As you can see 2 tests passed.

• FirstTests

• LoadProviders

• LoadProvidersNoDatabases failed and as you can see in the Message the text from the exception we threw is loaded there.

These are simple and straight forward tests that take very little time to add to your application. Next we will start getting deeper and testing the user flow so what happens when someone signs up.

Nunit is a unit testing framework for .NET, it was ported from a Java called JUnit.

More About NUnit here. My earlier post about Testing and Unit testing About Unit Testing

Getting Started with NUnit

It's easy to add Nunit, just Create a new Class Library on your project.

Then run Package installer and install the nuget package to the new class library

PM > Install-Package NUnit

Nuget here

Then in your new Class Library create a new Class - DemoTests, our first test will look like this.

[TestFixture]
class DemoTest
{

    [Test]
    public void FirstTest()
    {

        Assert.IsTrue(true, "Hello Test World!");
    }
}

[TestFixture]

Is added to the class, this will tell the test running that this class is for tests. But it has alot more power we'll get into that later in other posts.

Our First test method is simple.

[Test]

Tells the test running that this is a test.

Assert.IsTrue(true, "Hello Test World!");

Assert.IsTrue is how we tell the test has passed, failed or something else has happened.

Running the Test

But enough it's time to run the test. First thing, Add a reference to your Tests Libarary and reference the main project.

Then on the test page in Visual Studio 2017 you have an icon, on the right margin. When you mouse over it, it says "NUnit Test (click to run)"

Click it! Go on Click it,

And then hit run!

If you clicked it you have now run your first test congratulations.

I didn't have the NUnit Test Adapater installed at the time of running this test. I didn't need it, Visual Studio knows enough about the tests to be able to run it.

Go ahead and install it and do the whole restart of Visual Studio.

Once your back in go to "Test - Windows - Test Explorer"

This will open the Test Explorer window in Visual Studio and our "FirstTest" should be listed there. (If it isn't build the project, I find sometimes I have to run the web app in some cases to get VS to pick up my tests first)

You know what to do. Click run and lets watch what happens.

The test runs and passes because we told it to and we also see how long it took and we've green everywhere.

I don't know about you but sometimes I don't trust a test has worked until I can watch it fail so lets make it fail.

This is easy to do, in the First test change the Assert.IsTrue line.

Assert.IsTrue(false, "Test has Failed!");

We've changed it to be false and also changed the note that will be output.

So when we run this test now it will fail.

As you can see our first test has failed. We see the message we have loaded in as well in the output so we know why it failed.

Next time on Serversncode

As you can see it is really easy to create a NUnit test in Visual Studio 2017 but this is a very simple set of tests. Next Time around we'll start building some more detail tests. Getting into testing our Database connection and how do we test user signups.

I'll also go into how to wire into Visual Team Services and the full CI / CD and how to get these Unit tests to be a part of that process.

Next Part Real Nunit Tests