Click here to Skip to main content
15,885,914 members
Articles / Programming Languages / Visual Basic

CuttingEdge.Conditions

Rate me:
Please Sign up or sign in to vote.
4.59/5 (19 votes)
23 Jun 2011MIT3 min read 125K   67   84  
A pre- and postcondition validation framework based on .NET 3.5 extension methods
#region Copyright (c) 2009 S. van Deursen
/* The CuttingEdge.Conditions library enables developers to validate pre- and postconditions in a fluent 
 * manner.
 * 
 * To contact me, please visit my blog at http://www.cuttingedge.it/blogs/steven/ 
 *
 * Copyright (c) 2009 S. van Deursen
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
 * associated documentation files (the "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the
 * following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all copies or substantial
 * portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
 * LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO
 * EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#endregion

using System;

using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace CuttingEdge.Conditions.UnitTests.NullTests
{
    /// <summary>
    /// Tests the ValidatorExtensions.IsNotNull method.
    /// </summary>
    [TestClass]
    public class NullIsNotNullTests
    {
        [TestMethod]
        [ExpectedException(typeof(ArgumentNullException))]
        [Description("Calling IsNotNull on null should fail.")]
        public void IsNotNullTest1()
        {
            object o = null;
            Condition.Requires(o).IsNotNull();
        }

        [TestMethod]
        [Description("Calling IsNotNull on a reference should pass.")]
        public void IsNotNullTest2()
        {
            object o = new object();
            Condition.Requires(o).IsNotNull();
        }

        [TestMethod]
        [ExpectedException(typeof(ArgumentNullException))]
        [Description("Calling IsNotNull on a null Nullable<T> should fail.")]
        public void IsNotNullTest3()
        {
            int? i = null;
            Condition.Requires(i).IsNotNull();
        }

        [TestMethod]
        [Description("Calling IsNotNull on a set Nullable<T> should pass.")]
        public void IsNotNullTest4()
        {
            int? i = 3;
            Condition.Requires(i).IsNotNull();
        }

        [TestMethod]
        [Description("Calling IsNotNull with conditionDescription parameter should pass.")]
        public void IsNotNullTest5()
        {
            object o = new object();
            Condition.Requires(o).IsNotNull(string.Empty);
        }

        [TestMethod]
        [Description("Calling a failing IsNotNull should throw an Exception with an exception message that contains the given parameterized condition description argument.")]
        public void IsNotNullTest6()
        {
            object o = null;
            try
            {
                Condition.Requires(o, "o").IsNotNull("qwe {0} xyz");
                Assert.Fail();
            }
            catch (ArgumentException ex)
            {
                Assert.IsTrue(ex.Message.Contains("qwe o xyz"));
            }
        }

        [TestMethod]
        [Description("Calling IsNotNull on Nullable<T> with conditionDescription parameter should pass.")]
        public void IsNotNullTest7()
        {
            int? i = 4;
            Condition.Requires(i).IsNotNull(string.Empty);
        }

        [TestMethod]
        [Description("Calling a failing IsNotNull on Nullable<T> should throw an Exception with an exception message that contains the given parameterized condition description argument.")]
        public void IsNotNullTest8()
        {
            int? i = null;
            try
            {
                Condition.Requires(i, "i").IsNotNull("qwe {0} xyz");
                Assert.Fail();
            }
            catch (ArgumentException ex)
            {
                Assert.IsTrue(ex.Message.Contains("qwe i xyz"));
            }
        }

        [TestMethod]
        [Description("Calling IsNotNull on null should succeed when exceptions are suppressed.")]
        public void IsNotNullTest9()
        {
            object o = null;
            Condition.Requires(o).SuppressExceptionsForTest().IsNotNull();
        }
    }
}

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article, along with any associated source code and files, is licensed under The MIT License


Written By
Software Developer (Senior)
Netherlands Netherlands
I'm a freelance developer from the Netherlands, working with .NET technology on a daily basis, and officially diagnosed as a workaholic.

Comments and Discussions