Test files helper to manage loading files with test data or generating temp test files

FilesHelper

using System;
using System.IO;
using System.Reflection;

namespace Tests.Helpers
{
	/// <summary>
	/// Assists working with test files.
	/// </summary>
	/// <remarks>By default this class assumes your test files will be located
	/// in project folder "TestFiles". It's convenient.</remarks>
	public static class FilesHelper
	{
		private const string DefaultTestFilesPath = @"..\..\TestFiles";
		private const string DefaultTempFilesPath = "TempFiles";
		private static string _assemblyPath;

		static FilesHelper()
		{
			TestFilesPath = DefaultTestFilesPath;
			InitWithAssembly( Assembly.GetCallingAssembly() ); 
		}

		/// <summary>
		/// Initializes helper with assembly.
		/// </summary>
		/// <param name="assembly">The assembly.</param>
		/// <remarks>Test files are looked for relative to this assembly.</remarks>
		public static void InitWithAssembly ( Assembly assembly )
		{
			var uriPath = new Uri( assembly.GetName( false ).CodeBase );
			_assemblyPath = Path.GetDirectoryName( uriPath.LocalPath );
		}

		/// <summary>
		/// Gets the assembly path.
		/// </summary>
		/// <value>The assembly path.</value>
		public static string AssemblyPath
		{
			get
			{
				return _assemblyPath;
			}
		}

		/// <summary>
		/// Gets the test files path.
		/// </summary>
		/// <value>The test files path.</value>
		public static string TestFilesFullPath
		{
			get
			{
				return GetDirectory( Path.Combine( AssemblyPath, TestFilesPath ));
			}
		}

		/// <summary>
		/// Gets or sets the relative test files path.
		/// </summary>
		/// <value>The test files path.</value>
		/// <remarks>Defaults to "..\..\TestFiles\"</remarks>
		public static string TestFilesPath { get; set; }

		/// <summary>
		/// Gets or sets the test files group folder.
		/// </summary>
		/// <value>The test files group folder.</value>
		/// <remarks>If specified, folder name is inserted into test file path, right before file name.
		/// <para>This is useful to group test files for different tests. Set this property before in tests set up.</para>
		/// <para>Remember, property is static, so it will carry over to other tests. Set it to <c>string.Empty</c> to reset resolution back to parent tests folder.</para>
		/// <para>This property has no effect on temp files folder.</para>
		/// <example>Example of how code this would influence test file resolution.
		/// <code>
		/// FilesHelper.GroupFolder = string.Empty; // default
		/// var path = GetTestFilePath( "test.xml" ); // returns "TestFiles\test.xml"
		/// 
		/// FilesHelper.GroupFolder = "t2";
		/// var path = GetTestFilePath( "test.xml" ); // returns "TestFiles\t2\test.xml"
		/// </code></example></remarks>
		public static string GroupFolder{ get; set; }

		/// <summary>
		/// Gets the test file path.
		/// </summary>
		/// <param name="fileName">Name of the file.</param>
		/// <returns>Path to the specified test file.</returns>
		/// <remarks>Current <see cref="GroupFolder"/> is used to figure out full file path.</remarks>
		public static string GetTestFilePath( string fileName )
		{
			var groupPath = Path.Combine( GroupFolder, fileName ); 
			return Path.Combine( TestFilesFullPath, groupPath );
		}

		/// <summary>
		/// Gets the test file path without group.
		/// </summary>
		/// <param name="fileName">Name of the file.</param>
		/// <returns>Path to the specified file.</returns>
		public static string GetTestFilePathWithoutGroup( string fileName )
		{
			return Path.Combine( TestFilesFullPath, fileName );
		}

		/// <summary>
		/// Gets the temp test file path.
		/// </summary>
		/// <returns>Path to a random test file.</returns>
		/// <remarks>Random file name is generated in temp folder and returned.</remarks>
		public static string GetTempTestFilePath()
		{
			return GetTempTestFilePath( Path.GetRandomFileName() );
		}

		/// <summary>
		/// Gets the temp test file path.
		/// </summary>
		/// <param name="fileName">Name of the file.</param>
		/// <returns>Path to the specified temp file.</returns>
		public static string GetTempTestFilePath( string fileName )
		{
			return Path.Combine( TempFolderPath, fileName ); 
		}

		/// <summary>
		/// Gets the temp folder path where temp files are stored.
		/// </summary>
		/// <value>The temp folder path.</value>
		public static string TempFolderPath
		{
			get
			{
				return GetDirectory( Path.Combine( TestFilesFullPath, DefaultTempFilesPath ) );  
			}
		}

		/// <summary>
		/// Deletes all temp folder.
		/// </summary>
		/// <remarks>Use this with care, since all files will be deleted.</remarks>
		public static void DeleteTempFiles()
		{
			if( Directory.Exists( TempFolderPath ) )
			{
				Directory.Delete( TempFolderPath, true ); 
			}
		}

		/// <summary>
		/// Gets the full directory.
		/// </summary>
		/// <param name="path">The path.</param>
		/// <returns>Absolute directory path.</returns>
		/// <remarks>Creates directory if it doesn't exist.</remarks>
		private static string GetDirectory( string path )
		{
			var dir = new DirectoryInfo( path );
			if( !dir.Exists )
				dir.Create();

			return dir.FullName;
		}
	}
}