Catel - Part 4 of n: Unit testing with Catel

using System.IO;
using Catel.Security.Cryptography;
using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace Catel.Test.Security.Cryptography
{
    [TestClass]
    public class CryptHelperTest
    {
        #region Constants
        /// <summary>
        /// The file content that will used to calculate the hash.
        /// </summary>
        private const string Content = "abcdefghijklmnopqrstuvwxyz";

        /// <summary>
        /// The actual hash of the content.
        /// </summary>
        private const string ContentHash = "C3FCD3D76192E4007DFB496CCA67E13B";

        /// <summary>
        /// The hash of an empty string ("").
        /// </summary>
        private const string EmptyContentHash = "D41D8CD98F00B204E9800998ECF8427E";
        #endregion

        #region Variables
        private FilesHelper _filesHelper = new FilesHelper();
        #endregion

        #region Initialization and cleanup
        /// <summary>
        /// Cleans up.
        /// </summary>
        [TestCleanup]
        public void CleanUp()
        {
            if (_filesHelper != null)
            {
                _filesHelper.CleanUp();
                _filesHelper = null;
            }
        }
        #endregion

        #region CalculateMD5FileHash
        [TestMethod]
        public void CalculateMD5FileHash()
        {
            string fileName = _filesHelper.GetTempFileName();
            using (TextWriter textWriter = new StreamWriter(fileName))
            {
                textWriter.Write(Content);
            }

            string actualHash = CryptHelper.CalculateMD5FileHash(fileName);

            Assert.AreEqual(ContentHash, actualHash);
        }

        [TestMethod]
        public void CalculateMD5FileHashWithEmpyFile()
        {
            Assert.AreEqual(string.Empty, CryptHelper.CalculateMD5FileHash(""));
            Assert.AreEqual(string.Empty, CryptHelper.CalculateMD5FileHash(null));
        }
        #endregion

        #region CalculateMD5ContentHash
        [TestMethod]
        public void CalculateMD5ContentHash()
        {
            string actualHash = CryptHelper.CalculateMD5ContentHash(Content);

            Assert.AreEqual(ContentHash, actualHash);
        }

        [TestMethod]
        public void CalculateMD5ContentHashWithEmpyContent()
        {
            Assert.AreEqual(EmptyContentHash, CryptHelper.CalculateMD5ContentHash(""));
            Assert.AreEqual(string.Empty, CryptHelper.CalculateMD5ContentHash(null));
        }
        #endregion
    }
}