Criteria

A criteria enables you to specify your Logical Intent for your Act part of a test.

Usage

You use a criteria in a Case as the first argument of RunTest method call.

using NUnit.Framework;
using static SmartTests.SmartTest;

[TestFixture]
public class MathTest
{
    [Test]
    public void Sqrt_ValueGreaterThanMin()
    {
        var result = RunTest( Case( MinIncluded.IsAboveMin ),
                              () => Math.Sqrt(2) );

        Assert.AreEqual( 2, result );
    }
}

Fortunately, if you only need one Case, you can omit it by calling another RunTest overload.

using NUnit.Framework;
using static SmartTests.SmartTest;

[TestFixture]
public class MathTest
{
    [Test]
    public void Sqrt_ValueGreaterThanMin()
    {
        var result = RunTest( MinIncluded.IsAboveMin,
                              () => Math.Sqrt(2) );

        Assert.AreEqual( 2, result );
    }
}

What is a Criteria

A Criteria has several criterion, each for a specific case of a logical intent.

For example, the MinIncluded criteria is used when you have a minimum value (for your property, parameter...).

All values below this minimum value is an error.
Minimum value is correct.
All values above this minimum value is correct.

Technically, a criteria is a subclass of Criteria class, that defines public static read-only fields only of its own type, one for each Logical Criterion.

Thus, for MinIncluded, we have this class:

public class MinIncluded : Criteria
{
    [Error]
    public static readonly Criteria IsBelowMin = new MinIncluded();
    public static readonly Criteria IsMin = new MinIncluded();
    public static readonly Criteria IsAboveMin = new MinIncluded();
}

As you can see in the previous example, the [Error] attribute specifies which criterion are errors.

Smart Test Analyzer

When you create a test with a criteria, the Smart Test Analyzer generates a warning message specifying that your test need two other tests: MinIncluded.IsBelowMin and MinIncluded.IsMin.

This way, your test is clearer and you do not forget to write tests.

This enables you to have a Logical Coverage, independently of the source code of your tested member.

Existing Criteria

Currently, predefined Criteria are the following:

Value with 1 limit

Value with 2 limits

Comparisons

Collections

Valid Values

Others

NotifyPropertyChanged

Ranges

Since v1.4, we can define criteria as ranges of integer values. It enables you to show logical equivalence groups right in your tests.

For more information, see Ranges.

Since v1.5, we can define criteria as ranges of floating point numbers.

For more information, see Ranges.

Enums

Since v1.6, we can define criteria as enum values. For more information, see Enums

We will add other Criteria.

Combining Criteria

Sometimes, you have several intents that are orthogonal for your test.

For example, your property as a minimum value (see MinIncluded) and should raised an event when changed (see NotifyPropertyChanged).

You only have to combine Criteria to achieve your goal.

Adding Criteria

If you cannot express your intent with this predefined criteria, you can create your own.

SmartTests/doc/Criteria/readme.md