NUnit

To make NUnit tests runnable in visual studio you also need to install the NUnit3TestAdapter. This allows visual studio’s test runner to recognise the NUnit tests.

You can add a new testing project by RMB clicking on the project file and going to Add -> New Project and then selecting the C# -> Tests section and choosing a test project. The accepted naming convention for these projects is NameOfProject.UnitTests, or some other test descriptor separate by a . period.

You can indicate test classes by using the [TestFixture] decorator. The convention for test class naming is NAME_OF_CLASSTests so if we were testing a class called User the associated test class would be UserTests.

using NUnit.Framework;

[TestFixture]
public class MyClassTests
{
  // test methods here
}

You can indicate test methods with the [Test] decorator. The convention for naming test methods is the form TestName_Scenario_ExpectedResult.

[Test]
public void MyMethod_IsTrue_ReturnsName
{
  // test method code here
}

Test methods should follow an Arrange, Act, Assert test pattern. First you arrange any test set up, then you run your code, then you make an assertion against the result.

[Test]
public void IsAdult_AgeGreaterThan18_ReturnsTrue
{
  // Arrange
  var user = new User();

  // Act
  result = user.IsRegistered();

  // Assert
  Assert.IsTrue(result);
}

Assertions

You can make assertions using the Assert object followed by a matcher object.

You can add hardcoded passing test skips by using the pass method on the Assert object.

[Test]
public TestWillAlwaysPass()
{
  Assert.pass();
}

You can assert that something is true in several ways:

• Using the IsTrue method on Assert.
• Using the That method of Assert with a boolean evaluating expression.
• Using the That method of Assert with a boolean property on the Is object as an argument.

All of these essentially evaluate to the same thing but just offer better semantic information on the purpose of the test.

Assert.IsTrue(result);
Assert.That(result == true);
Assert.That(result, Is.True);

You can assert that two things are equal by using the boolean matchers above.

int i = 1;
Assert.IsTrue(i == 1);