/src/NUnit/framework/Attributes/ValuesAttribute.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>

    /// Abstract base class for attributes that apply to parameters 

    /// and supply data for the parameter.

    /// </summary>

    [AttributeUsage(AttributeTargets.Parameter, AllowMultiple = false, Inherited = false)]

    public abstract class ParameterDataAttribute : Attribute

    {

        /// <summary>

        /// Gets the data to be provided to the specified parameter

        /// </summary>

        public abstract IEnumerable GetData(ParameterInfo parameter);

    }



    /// <summary>

    /// ValuesAttribute is used to provide literal arguments for

    /// an individual parameter of a test.

    /// </summary>

    [AttributeUsage(AttributeTargets.Parameter, AllowMultiple = false, Inherited = false)]

    public class ValuesAttribute : ParameterDataAttribute

    {

        /// <summary>

        /// The collection of data to be returned. Must

        /// be set by any derived attribute classes.

        /// We use an object[] so that the individual

        /// elements may have their type changed in GetData

        /// if necessary.

        /// </summary>

        // TODO: This causes a lot of boxing so we should eliminate it.

        protected object[] data;



        /// <summary>

        /// Construct with one argument

        /// </summary>

        /// <param name="arg1"></param>

        public ValuesAttribute(object arg1)

        {

            data = new object[] { arg1 };

        }



        /// <summary>

        /// Construct with two arguments

        /// </summary>

        /// <param name="arg1"></param>

        /// <param name="arg2"></param>

        public ValuesAttribute(object arg1, object arg2)

        {

            data = new object[] { arg1, arg2 };

        }



        /// <summary>

        /// Construct with three arguments

        /// </summary>

        /// <param name="arg1"></param>

        /// <param name="arg2"></param>

        /// <param name="arg3"></param>

        public ValuesAttribute(object arg1, object arg2, object arg3)

        {

            data = new object[] { arg1, arg2, arg3 };

        }



        /// <summary>

        /// Construct with an array of arguments

        /// </summary>

        /// <param name="args"></param>

        public ValuesAttribute(params object[] args)

        {

            data = args;

        }



        /// <summary>

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

        /// </summary>

        public override IEnumerable GetData(ParameterInfo parameter)

        {

            Type targetType = parameter.ParameterType;



            for (int i = 0; i < data.Length; i++)

            {

                object arg = data[i];



                if (arg == null) 

                    continue;



                if (arg.GetType().FullName == "NUnit.Framework.SpecialValue" &&

                    arg.ToString() == "Null")

                {

                    data[i] = null;

                    continue;

                }



                if (targetType.IsAssignableFrom(arg.GetType()))

                    continue;



                if (arg is DBNull)

                {

                    data[i] = null;

                    continue;

                }



                bool convert = false;



                if (targetType == typeof(short) || targetType == typeof(byte) || targetType == typeof(sbyte))

                    convert = arg is int;

                else

                    if (targetType == typeof(decimal))

                        convert = arg is double || arg is string || arg is int;

                    else

                        if (targetType == typeof(DateTime) || targetType == typeof(TimeSpan))

                            convert = arg is string;



                if (convert)

                    data[i] = Convert.ChangeType(arg, targetType, System.Globalization.CultureInfo.InvariantCulture);

            }



			return data;

        }

    }

}