mjuraszek-iconvertible-tests

    class ConvertTest : ITestable
    {
        private static class TestClass<T> where T : IConvertible
        {
            public static int GetInt(T x)
            {
                return Convert.ToInt32(x);
            }

            public static T GetT(int x)
            {
                return (T)Convert.ChangeType(x, typeof(T));
            }
        }
    }

    class ExpressionTreeTest : ITestable
    {
        private static class TestClass<T> where T : IConvertible
        {
            static Func<T, int> _getInt;
            static Func<int, T> _getT;

            static TestClass()
            {
                var param = Expression.Parameter(typeof(int), "x");
                UnaryExpression body = Expression.Convert(param, typeof(T));
                _getT = Expression.Lambda<Func<int, T>>(body, param).Compile();

                param = Expression.Parameter(typeof(T), "x");
                body = Expression.Convert(param, typeof(int));
                _getInt = Expression.Lambda<Func<T, int>>(body, param).Compile();
            }

            public static int GetInt(T x)
            {
                return _getInt(x);
            }

            public static T GetT(int x)
            {
                return _getT(x);
            }
        }
    }

    class IConvertibleTest : ITestable
    {
        private static class TestClass<T> where T : IConvertible
        {
            public static int GetInt(T x)
            {
                return x.ToInt32(null);
            }

            public static T GetT(int x)
            {
                // horrible, isn't it?!
                return (T)((IConvertible)x).ToType(typeof(T), null);
            }
        }
    }