/src/NUnit/framework/Attributes/RandomAttribute.cs

// ****************************************************************

// Copyright 2008, Charlie Poole

// This is free software licensed under the NUnit license. You may

// obtain a copy of the license at http://nunit.org

// ****************************************************************



using System;

using System.Collections;

using System.Reflection;



namespace NUnit.Framework

{

    /// <summary>

    /// RandomAttribute is used to supply a set of random values

    /// to a single parameter of a parameterized test.

    /// </summary>

    public class RandomAttribute : ValuesAttribute

    {

        enum SampleType

        {

            Raw,

            IntRange,

            DoubleRange

        }



        SampleType sampleType;

        private int count;

        private int min, max;

        private double dmin, dmax;



        /// <summary>

        /// Construct a set of doubles from 0.0 to 1.0,

        /// specifying only the count.

        /// </summary>

        /// <param name="count"></param>

        public RandomAttribute(int count)

        {

            this.count = count;

            this.sampleType = SampleType.Raw;

        }



        /// <summary>

        /// Construct a set of doubles from min to max

        /// </summary>

        /// <param name="min"></param>

        /// <param name="max"></param>

        /// <param name="count"></param>

        public RandomAttribute(double min, double max, int count)

        {

            this.count = count;

            this.dmin = min;

            this.dmax = max;

            this.sampleType = SampleType.DoubleRange;

        }



        /// <summary>

        /// Construct a set of ints from min to max

        /// </summary>

        /// <param name="min"></param>

        /// <param name="max"></param>

        /// <param name="count"></param>

        public RandomAttribute(int min, int max, int count)

        {

            this.count = count;

            this.min = min;

            this.max = max;

            this.sampleType = SampleType.IntRange;

        }



        /// <summary>

        /// Get the collection of values to be used as arguments

        /// </summary>

        public override IEnumerable GetData(ParameterInfo parameter)

        {

            Randomizer r = Randomizer.GetRandomizer(parameter);

            IList values;



            switch (sampleType)

            {

                default:

                case SampleType.Raw:

                    values = r.GetDoubles(count);

                    break;

                case SampleType.IntRange:

                    values = r.GetInts(min, max, count);

                    break;

                case SampleType.DoubleRange:

                    values = r.GetDoubles(dmin, dmax, count);

                    break;

            }



            // Copy the random values into the data array

            // and call the base class which may need to

            // convert them to another type.

            this.data = new object[values.Count];

            for (int i = 0; i < values.Count; i++)

                this.data[i] = values[i];



            return base.GetData(parameter);

        }

    }

}