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

  1// ****************************************************************
  2// Copyright 2008, Charlie Poole
  3// This is free software licensed under the NUnit license. You may
  4// obtain a copy of the license at http://nunit.org
  5// ****************************************************************
  6
  7using System;
  8using System.Collections;
  9using System.Reflection;
 10
 11namespace NUnit.Framework
 12{
 13    /// <summary>
 14    /// RandomAttribute is used to supply a set of random values
 15    /// to a single parameter of a parameterized test.
 16    /// </summary>
 17    public class RandomAttribute : ValuesAttribute
 18    {
 19        enum SampleType
 20        {
 21            Raw,
 22            IntRange,
 23            DoubleRange
 24        }
 25
 26        SampleType sampleType;
 27        private int count;
 28        private int min, max;
 29        private double dmin, dmax;
 30
 31        /// <summary>
 32        /// Construct a set of doubles from 0.0 to 1.0,
 33        /// specifying only the count.
 34        /// </summary>
 35        /// <param name="count"></param>
 36        public RandomAttribute(int count)
 37        {
 38            this.count = count;
 39            this.sampleType = SampleType.Raw;
 40        }
 41
 42        /// <summary>
 43        /// Construct a set of doubles from min to max
 44        /// </summary>
 45        /// <param name="min"></param>
 46        /// <param name="max"></param>
 47        /// <param name="count"></param>
 48        public RandomAttribute(double min, double max, int count)
 49        {
 50            this.count = count;
 51            this.dmin = min;
 52            this.dmax = max;
 53            this.sampleType = SampleType.DoubleRange;
 54        }
 55
 56        /// <summary>
 57        /// Construct a set of ints from min to max
 58        /// </summary>
 59        /// <param name="min"></param>
 60        /// <param name="max"></param>
 61        /// <param name="count"></param>
 62        public RandomAttribute(int min, int max, int count)
 63        {
 64            this.count = count;
 65            this.min = min;
 66            this.max = max;
 67            this.sampleType = SampleType.IntRange;
 68        }
 69
 70        /// <summary>
 71        /// Get the collection of values to be used as arguments
 72        /// </summary>
 73        public override IEnumerable GetData(ParameterInfo parameter)
 74        {
 75            Randomizer r = Randomizer.GetRandomizer(parameter);
 76            IList values;
 77
 78            switch (sampleType)
 79            {
 80                default:
 81                case SampleType.Raw:
 82                    values = r.GetDoubles(count);
 83                    break;
 84                case SampleType.IntRange:
 85                    values = r.GetInts(min, max, count);
 86                    break;
 87                case SampleType.DoubleRange:
 88                    values = r.GetDoubles(dmin, dmax, count);
 89                    break;
 90            }
 91
 92            // Copy the random values into the data array
 93            // and call the base class which may need to
 94            // convert them to another type.
 95            this.data = new object[values.Count];
 96            for (int i = 0; i < values.Count; i++)
 97                this.data[i] = values[i];
 98
 99            return base.GetData(parameter);
100        }
101    }
102}