Can NUnit be used for Functional and Regression testing?

Question

Now, here the confusion starts. I was creating some test cases using Selenium WebDriver with C# and thought of using a testing framework.

My task is to create functional test cases which can later be used for Regression testing of the application; only for the +ve flows, like if a new build come, I will execute that test suite and will see major functionalities like 'creating a user with valid values' is working or not?. So, this is the main purpose of automated test cases to capture +ve flows which can be re-run N number of times.

I started using NUnit + Selenium WebDriver for the same and created few test cases for my first presentation/demo. In the meantime, I contacted a developer who told me he is creating his unit test cases in NUnit. So, I went back to NUnit site whose very first line states that

What Is NUnit?

NUnit is a unit-testing framework for all .Net languages.

Then, I got this blog link over some web search and it confused me totally, as may be asked some questions in presentation. I know it may depend upon how we use this framework but still have queries to clear.

Questions:

1. Is NUnit only a Unit testing framework? If Yes, then it means I am creating unit test cases which a developer is already doing. So, my work is not adding any value.
2. Can NUnit be used for Functional/Regression testing? If Yes, then
   • How it can be used? and
   • Why NUnit says it is a unit testing framework?

I may be asked these questions, so need to prepare for the same.

Answer 1

Is NUnit only a Unit testing framework?

NUint is a .Net port (commonly used with Visual Studio) of JUnit (which is commonly used with Eclipse). So it's different than the standard 'unit tests' in a VS project. Generally those unit test are testing each function of the application. xUnit tests do test through the UI level. I think your hangup is on the term 'unit test', which simply means testing a single function.

Can NUnit be used for Functional/Regression testing?

You can chain xUnit tests to do a full UI regression without using Microsoft Test Manager or Visual Studio Pro. NUnit runs tests in alphabetical order so I got into the habit of using a number convention so it's easier to slip in new tests, like '010 - Login' then '020 - Update Profile'.

Answer 2

Yes, you can use NUnit for functional testing. But still it is a unit-testing framework. No, you are not creating unit-tests by using a unit-testing framework to write functional tests. A unit-test is testing just a single methods input and output, by writing end-2-end tests it by definition cannot be a unit-test. :)

Unit testing frameworks are often combined with other testing frameworks like Selenium or Specflow to write functional tests. NUnit is in that case used as test-runner and assert framework. I think using the same tooling base for all your tests simplifies installation and knowledge needed to build and run tests.

NUnit is designed for unit-testing, that you can combine it with other software is nice, but not the development teams focus. Thus they call it a unit-testing framework.

Answer 3

We're using NUnit as test runner for Specflow for our functional and regression tests.