Catel - Part 4 of n: Unit testing with Catel

using System;
using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace Catel.Test.IO
{
    [TestClass]
    public class DirectoryTest
    {
        #region DirectoryExists
        [TestMethod]
        public void DirectoryExists_ExistingDirectory()
        {
            // Declare variables
            string input = @"C:\Windows\";
            bool expectedOutput = true;

            // Call method
            bool output = Catel.IO.Directory.Exists(input);

            // Check result
            Assert.AreEqual(expectedOutput, output);
        }

        [TestMethod]
        public void DirectoryExists_NonExistingDirectory()
        {
            // Declare variables
            string input = @"C:\MyWindows\";
            bool expectedOutput = false;

            // Call method
            bool output = Catel.IO.Directory.Exists(input);

            // Check result
            Assert.AreEqual(expectedOutput, output);
        }

        [TestMethod]
        public void DirectoryExists_Null()
        {
            try
            {
                Catel.IO.Directory.Exists(null);
                Assert.Fail("Expected exception");
            }
            catch (ArgumentException ex)
            {
                Assert.AreEqual("directory", ex.ParamName);
            }
        }

        [TestMethod]
        public void DirectoryExists_EmptyParameter()
        {
            Assert.AreEqual(false, Catel.IO.Directory.Exists(string.Empty));
        }
        #endregion

        #region DeleteDirectory
        [TestMethod]
        public void DeleteDirectory()
        {
            // Get temporary directory
            string baseDirectory = Catel.IO.Path.Combine(System.IO.Path.GetTempPath(), "DeleteDirectoryTest");

            // Create test directories (5 levels deep)
            CreateDirectories(baseDirectory, 5);

            // Now remove the directories again
            bool output = Catel.IO.Directory.Delete(baseDirectory);

            // Validate output
            Assert.AreEqual(true, output);
            Assert.AreEqual(false, Catel.IO.Directory.Exists(baseDirectory));
        }
        #endregion

        #region Helper methods
        /// <summary>
        /// Creates a lot of directories with subdirectories and files.
        /// </summary>
        /// <param name="directory">The directory.</param>
        /// <param name="depth">The number of subdirectories to create.</param>
        public void CreateDirectories(string directory, int depth)
        {
            // Create directory
            System.IO.Directory.CreateDirectory(directory);

            // Create files in directory
            CreateFilesInDirectory(directory);

            // Should we still create directories?
            if (depth > 0)
            {
                // Create 10 subdirectories
                for (int i = 1; i < 5; i++)
                {
                    // Create subdirectory
                    CreateDirectories(Catel.IO.Path.Combine(directory, i.ToString()), depth - 1);
                }
            }
        }

        /// <summary>
        /// Creates 10 dummy files in the directory.
        /// </summary>
        /// <param name="directory">The directory.</param>
        private void CreateFilesInDirectory(string directory)
        {
            // Create files
            for (int i = 1; i <= 10; i++)
            {
                // Get filepath & create file
                string filePath = Catel.IO.Path.Combine(directory, i + ".dat");
                using (System.IO.FileStream fileStream = System.IO.File.Create(filePath))
                {
                    // If you want, write something to the file
                }
            }
        }
        #endregion
    }
}