[Tests] Fix flaky IO tests due to parrallel execution on Mac bots. (#5965)

3 files changed, 121 insertions, 106 deletions

diff --git a/mcs/class/corlib/Test/System.IO/FileTest.cs b/mcs/class/corlib/Test/System.IO/FileTest.cs
index 886d65d6393..e9300c82c7b 100644
--- a/mcs/class/corlib/Test/System.IO/FileTest.cs
+++ b/mcs/class/corlib/Test/System.IO/FileTest.cs
@@ -25,13 +25,16 @@ namespace MonoTests.System.IO
 	public class FileTest
 	{
 		CultureInfo old_culture;
-		static string TempFolder = Path.Combine (Path.GetTempPath (), "MonoTests.System.IO.Tests");
+		string tmpFolder;
 
 		[SetUp]
 		public void SetUp ()
 		{
-			DeleteDirectory (TempFolder);
-			Directory.CreateDirectory (TempFolder);
+			tmpFolder = Path.GetTempFileName ();
+			if (File.Exists (tmpFolder))
+				File.Delete (tmpFolder);
+			DeleteDirectory (tmpFolder);
+			Directory.CreateDirectory (tmpFolder);
 			old_culture = Thread.CurrentThread.CurrentCulture;
 			Thread.CurrentThread.CurrentCulture = new CultureInfo ("en-US", false);
 		}
@@ -39,7 +42,7 @@ namespace MonoTests.System.IO
 		[TearDown]
 		public void TearDown ()
 		{
-			DeleteDirectory (TempFolder);
+			DeleteDirectory (tmpFolder);
 			Thread.CurrentThread.CurrentCulture = old_culture;
 		}
 
@@ -65,7 +68,7 @@ namespace MonoTests.System.IO
 		public void TestExists ()
 		{
 			FileStream s = null;
-			string path = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
 			try {
 				Assert.IsFalse (File.Exists (null), "#1");
 				Assert.IsFalse (File.Exists (string.Empty), "#2");
@@ -74,7 +77,7 @@ namespace MonoTests.System.IO
 				s = File.Create (path);
 				s.Close ();
 				Assert.IsTrue (File.Exists (path), "#4");
-				Assert.IsFalse (File.Exists (TempFolder + Path.DirectorySeparatorChar + "doesnotexist"), "#5");
+				Assert.IsFalse (File.Exists (tmpFolder + Path.DirectorySeparatorChar + "doesnotexist"), "#5");
 			} finally {
 				if (s != null)
 					s.Close ();
@@ -112,7 +115,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Create_Path_Directory ()
 		{
-			string path = Path.Combine (TempFolder, "foo");
+			string path = Path.Combine (tmpFolder, "foo");
 			Directory.CreateDirectory (path);
 			try {
 				File.Create (path);
@@ -146,7 +149,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Create_Path_ReadOnly ()
 		{
-			string path = Path.Combine (TempFolder, "foo");
+			string path = Path.Combine (tmpFolder, "foo");
 			File.Create (path).Close ();
 			File.SetAttributes (path, FileAttributes.ReadOnly);
 			try {
@@ -182,7 +185,7 @@ namespace MonoTests.System.IO
 		public void Create_Directory_DoesNotExist ()
 		{
 			FileStream stream = null;
-			string path = TempFolder + Path.DirectorySeparatorChar + "directory_does_not_exist" + Path.DirectorySeparatorChar + "foo";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "directory_does_not_exist" + Path.DirectorySeparatorChar + "foo";
 			
 			try {
 				stream = File.Create (path);
@@ -207,7 +210,7 @@ namespace MonoTests.System.IO
 			string path = null;
 
 			/* positive test: create resources/foo */
-			path = TempFolder + Path.DirectorySeparatorChar + "foo";
+			path = tmpFolder + Path.DirectorySeparatorChar + "foo";
 			try {
 
 				stream = File.Create (path);
@@ -222,7 +225,7 @@ namespace MonoTests.System.IO
 			stream = null;
 
 			/* positive test: repeat test above again to test for overwriting file */
-			path = TempFolder + Path.DirectorySeparatorChar + "foo";
+			path = tmpFolder + Path.DirectorySeparatorChar + "foo";
 			try {
 				stream = File.Create (path);
 				Assert.IsTrue (File.Exists (path), "#2");
@@ -339,8 +342,8 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Copy_DestFileName_AlreadyExists ()
 		{
-			string source = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
-			string dest = TempFolder + Path.DirectorySeparatorChar + "bar";
+			string source = tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
+			string dest = tmpFolder + Path.DirectorySeparatorChar + "bar";
 			DeleteFile (source);
 			DeleteFile (dest);
 			try {
@@ -365,7 +368,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Copy_SourceFileName_DestFileName_Same ()
 		{
-			string source = TempFolder + Path.DirectorySeparatorChar + "SameFile.txt";
+			string source = tmpFolder + Path.DirectorySeparatorChar + "SameFile.txt";
 			DeleteFile (source);
 			try {
 				// new empty file
@@ -386,8 +389,8 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Copy ()
 		{
-			string path1 = TempFolder + Path.DirectorySeparatorChar + "bar";
-			string path2 = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
+			string path1 = tmpFolder + Path.DirectorySeparatorChar + "bar";
+			string path2 = tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
 			/* positive test: copy resources/AFile.txt to resources/bar */
 			try {
 				DeleteFile (path1);
@@ -455,7 +458,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Delete_Directory_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "directory_does_not_exist" + Path.DirectorySeparatorChar + "foo";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "directory_does_not_exist" + Path.DirectorySeparatorChar + "foo";
 			if (Directory.Exists (path))
 				Directory.Delete (path, true);
 
@@ -474,7 +477,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Delete ()
 		{
-			string foopath = TempFolder + Path.DirectorySeparatorChar + "foo";
+			string foopath = tmpFolder + Path.DirectorySeparatorChar + "foo";
 			DeleteFile (foopath);
 			try {
 				File.Create (foopath).Close ();
@@ -490,7 +493,7 @@ namespace MonoTests.System.IO
 		[Category ("NotWorking")]
 		public void Delete_FileLock ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "DeleteOpenStreamException";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "DeleteOpenStreamException";
 			DeleteFile (path);
 			FileStream stream = null;
 			try {
@@ -520,7 +523,7 @@ namespace MonoTests.System.IO
 			if (RunningOnUnix)
 				Assert.Ignore ("ReadOnly files can be deleted on unix since fdef50957f508627928c7876a905d5584da45748.");
 
-			string path = TempFolder + Path.DirectorySeparatorChar + "DeleteReadOnly";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "DeleteReadOnly";
 			DeleteFile (path);
 			try {
 				File.Create (path).Close ();
@@ -546,7 +549,7 @@ namespace MonoTests.System.IO
 
 			FileAttributes attrs;
 
-			string path = Path.Combine (TempFolder, "GetAttributes.tmp");
+			string path = Path.Combine (tmpFolder, "GetAttributes.tmp");
 			File.Create (path).Close ();
 
 			attrs = File.GetAttributes (path);
@@ -565,7 +568,7 @@ namespace MonoTests.System.IO
 			if (RunningOnUnix)
 				Assert.Ignore ("bug #325181: FileAttributes.Archive has no effect on Unix.");
 
-			string path = Path.Combine (TempFolder, "GetAttributes.tmp");
+			string path = Path.Combine (tmpFolder, "GetAttributes.tmp");
 			File.Create (path).Close ();
 
 			FileAttributes attrs = File.GetAttributes (path);
@@ -581,7 +584,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void GetAttributes_Default_Directory ()
 		{
-			FileAttributes attrs = File.GetAttributes (TempFolder);
+			FileAttributes attrs = File.GetAttributes (tmpFolder);
 
 			Assert.IsFalse ((attrs & FileAttributes.Archive) != 0, "#1");
 			Assert.IsTrue ((attrs & FileAttributes.Directory) != 0, "#2");
@@ -594,16 +597,16 @@ namespace MonoTests.System.IO
 		[Test]
 		public void GetAttributes_Directory ()
 		{
-			FileAttributes attrs = File.GetAttributes (TempFolder);
+			FileAttributes attrs = File.GetAttributes (tmpFolder);
 
 			Assert.IsTrue ((attrs & FileAttributes.Directory) != 0, "#1");
 
 			attrs &= ~FileAttributes.Directory;
-			File.SetAttributes (TempFolder, attrs);
+			File.SetAttributes (tmpFolder, attrs);
 
 			Assert.IsFalse ((attrs & FileAttributes.Directory) != 0, "#2");
 
-			string path = Path.Combine (TempFolder, "GetAttributes.tmp");
+			string path = Path.Combine (tmpFolder, "GetAttributes.tmp");
 			File.Create (path).Close ();
 
 			attrs = File.GetAttributes (path);
@@ -618,7 +621,7 @@ namespace MonoTests.System.IO
 		{
 			FileAttributes attrs;
 
-			string path = Path.Combine (TempFolder, "GetAttributes.tmp");
+			string path = Path.Combine (tmpFolder, "GetAttributes.tmp");
 			File.Create (path).Close ();
 
 			attrs = File.GetAttributes (path);
@@ -643,7 +646,7 @@ namespace MonoTests.System.IO
 
 			FileAttributes attrs;
 
-			string path = Path.Combine (TempFolder, "GetAttributes.tmp");
+			string path = Path.Combine (tmpFolder, "GetAttributes.tmp");
 			File.Create (path).Close ();
 
 			attrs = File.GetAttributes (path);
@@ -659,7 +662,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void GetAttributes_Path_DoesNotExist ()
 		{
-			string path = Path.Combine (TempFolder, "GetAttributes.tmp");
+			string path = Path.Combine (tmpFolder, "GetAttributes.tmp");
 			try {
 				File.GetAttributes (path);
 				Assert.Fail ("#1");
@@ -791,7 +794,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Move_SourceFileName_DoesNotExist ()
 		{
-			string file = TempFolder + Path.DirectorySeparatorChar + "doesnotexist";
+			string file = tmpFolder + Path.DirectorySeparatorChar + "doesnotexist";
 			DeleteFile (file);
 			try {
 				File.Move (file, "b");
@@ -807,8 +810,8 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Move_DestFileName_DirectoryDoesNotExist ()
 		{
-			string sourceFile = TempFolder + Path.DirectorySeparatorChar + "foo";
-			string destFile = Path.Combine (Path.Combine (TempFolder, "doesnotexist"), "b");
+			string sourceFile = tmpFolder + Path.DirectorySeparatorChar + "foo";
+			string destFile = Path.Combine (Path.Combine (tmpFolder, "doesnotexist"), "b");
 			DeleteFile (sourceFile);
 			try {
 				File.Create (sourceFile).Close ();
@@ -830,13 +833,13 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Move_DestFileName_AlreadyExists ()
 		{
-			string sourceFile = TempFolder + Path.DirectorySeparatorChar + "foo";
+			string sourceFile = tmpFolder + Path.DirectorySeparatorChar + "foo";
 			string destFile;
 
 			// move to same directory
 			File.Create (sourceFile).Close ();
 			try {
-				File.Move (sourceFile, TempFolder);
+				File.Move (sourceFile, tmpFolder);
 				Assert.Fail ("#A1");
 			} catch (IOException ex) {
 				// Cannot create a file when that file already exists
@@ -844,14 +847,14 @@ namespace MonoTests.System.IO
 				Assert.IsNull (ex.InnerException, "#A3");
 				Assert.IsNotNull (ex.Message, "#A4");
 				Assert.IsFalse (ex.Message.IndexOf (sourceFile) != -1, "#A5");
-				Assert.IsFalse (ex.Message.IndexOf (TempFolder) != -1, "#A6");
+				Assert.IsFalse (ex.Message.IndexOf (tmpFolder) != -1, "#A6");
 			} finally {
 				DeleteFile (sourceFile);
 			}
 
 			// move to exist file
 			File.Create (sourceFile).Close ();
-			destFile = TempFolder + Path.DirectorySeparatorChar + "bar";
+			destFile = tmpFolder + Path.DirectorySeparatorChar + "bar";
 			File.Create (destFile).Close ();
 			try {
 				File.Move (sourceFile, destFile);
@@ -870,7 +873,7 @@ namespace MonoTests.System.IO
 
 			// move to existing directory
 			File.Create (sourceFile).Close ();
-			destFile = TempFolder + Path.DirectorySeparatorChar + "bar";
+			destFile = tmpFolder + Path.DirectorySeparatorChar + "bar";
 			Directory.CreateDirectory (destFile);
 			try {
 				File.Move (sourceFile, destFile);
@@ -891,8 +894,8 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Move ()
 		{
-			string bar = TempFolder + Path.DirectorySeparatorChar + "bar";
-			string baz = TempFolder + Path.DirectorySeparatorChar + "baz";
+			string bar = tmpFolder + Path.DirectorySeparatorChar + "bar";
+			string baz = tmpFolder + Path.DirectorySeparatorChar + "baz";
 			if (!File.Exists (bar)) {
 				FileStream f = File.Create(bar);
 				f.Close();
@@ -904,8 +907,8 @@ namespace MonoTests.System.IO
 			Assert.IsTrue (File.Exists (baz), "#3");
 
 			// Test moving of directories
-			string dir = Path.Combine (TempFolder, "dir");
-			string dir2 = Path.Combine (TempFolder, "dir2");
+			string dir = Path.Combine (tmpFolder, "dir");
+			string dir2 = Path.Combine (tmpFolder, "dir2");
 			string dir_foo = Path.Combine (dir, "foo");
 			string dir2_foo = Path.Combine (dir2, "foo");
 
@@ -965,7 +968,7 @@ namespace MonoTests.System.IO
 			string path = null;
 			FileStream stream = null;
 
-			path = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
+			path = tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
 			try {
 				if (!File.Exists (path))
 					stream = File.Create (path);
@@ -1009,7 +1012,7 @@ namespace MonoTests.System.IO
 			stream = null;
 
 			/* Exception tests */
-			path = TempFolder + Path.DirectorySeparatorChar + "filedoesnotexist";
+			path = tmpFolder + Path.DirectorySeparatorChar + "filedoesnotexist";
 			try {
 				stream = File.Open (path, FileMode.Open);
 				Assert.Fail ("#D1");
@@ -1028,10 +1031,10 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Open_CreateNewMode_ReadAccess ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
 			FileStream stream = null;
 			try {
-				stream = File.Open (TempFolder + Path.DirectorySeparatorChar + "AFile.txt", FileMode.CreateNew, FileAccess.Read);
+				stream = File.Open (tmpFolder + Path.DirectorySeparatorChar + "AFile.txt", FileMode.CreateNew, FileAccess.Read);
 				Assert.Fail ("#1");
 			} catch (ArgumentException ex) {
 				// Combining FileMode: CreateNew with FileAccess: Read is invalid
@@ -1049,7 +1052,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void Open_AppendMode_ReadAccess ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
 			FileStream s = null;
 			if (!File.Exists (path))
 				File.Create (path).Close ();
@@ -1072,7 +1075,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void OpenRead ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
 			if (!File.Exists (path))
 				File.Create (path).Close ();
 			FileStream stream = null;
@@ -1092,7 +1095,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void OpenWrite ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
 			if (!File.Exists (path))
 				File.Create (path).Close ();
 			FileStream stream = null;
@@ -1113,7 +1116,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void TestGetCreationTime ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "baz";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "baz";
 			DeleteFile (path);
 
 			try {
@@ -1170,7 +1173,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void LastAccessTime ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "lastAccessTime";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "lastAccessTime";
 			if (File.Exists (path))
 				File.Delete (path);
 			FileStream stream = null;
@@ -1217,7 +1220,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void LastWriteTime ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "lastWriteTime";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "lastWriteTime";
 			if (File.Exists (path))
 				File.Delete (path);
 			FileStream stream = null;
@@ -1293,7 +1296,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void GetCreationTime_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "GetCreationTimeException3";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "GetCreationTimeException3";
 			DeleteFile (path);
 
 			DateTime time = File.GetCreationTime (path);
@@ -1368,7 +1371,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void GetCreationTimeUtc_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "GetCreationTimeUtcException3";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "GetCreationTimeUtcException3";
 			DeleteFile (path);
 
 			DateTime time = File.GetCreationTimeUtc (path);
@@ -1442,7 +1445,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void GetLastAccessTime_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "GetLastAccessTimeException3";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "GetLastAccessTimeException3";
 			DeleteFile (path);
 
 			DateTime time = File.GetLastAccessTime (path);
@@ -1517,7 +1520,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void GetLastAccessTimeUtc_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "GetLastAccessTimeUtcException3";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "GetLastAccessTimeUtcException3";
 			DeleteFile (path);
 
 			DateTime time = File.GetLastAccessTimeUtc (path);
@@ -1591,7 +1594,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void GetLastWriteTime_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "GetLastAccessTimeUtcException3";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "GetLastAccessTimeUtcException3";
 			DeleteFile (path);
 
 			DateTime time = File.GetLastWriteTime (path);
@@ -1666,7 +1669,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void GetLastWriteTimeUtc_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "GetLastWriteTimeUtcException3";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "GetLastWriteTimeUtcException3";
 			DeleteFile (path);
 
 			DateTime time = File.GetLastWriteTimeUtc (path);
@@ -1711,7 +1714,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void FileStreamClose ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "FileStreamClose";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "FileStreamClose";
 			FileStream stream = null;
 			try {
 				stream = File.Create (path);
@@ -1792,7 +1795,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetCreationTime_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "SetCreationTimeFileNotFoundException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "SetCreationTimeFileNotFoundException1";
 			DeleteFile (path);
 			
 			try {
@@ -1810,7 +1813,7 @@ namespace MonoTests.System.IO
 //		[ExpectedException(typeof (ArgumentOutOfRangeException))]
 //		public void SetCreationTimeArgumentOutOfRangeException1 ()
 //		{
-//			string path = TempFolder + Path.DirectorySeparatorChar + "SetCreationTimeArgumentOutOfRangeException1";
+//			string path = tmpFolder + Path.DirectorySeparatorChar + "SetCreationTimeArgumentOutOfRangeException1";
 //			FileStream stream = null;
 //			DeleteFile (path);
 //			try {
@@ -1827,7 +1830,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetCreationTime_FileLock ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "CreationTimeIOException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "CreationTimeIOException1";
 			DeleteFile (path);
 			FileStream stream = null;
 			try {
@@ -1916,7 +1919,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetCreationTimeUtc_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "SetCreationTimeUtcFileNotFoundException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "SetCreationTimeUtcFileNotFoundException1";
 			DeleteFile (path);
 
 			try {
@@ -1934,7 +1937,7 @@ namespace MonoTests.System.IO
 //		[ExpectedException(typeof (ArgumentOutOfRangeException))]
 //		public void SetCreationTimeUtcArgumentOutOfRangeException1 ()
 //		{
-//			string path = TempFolder + Path.DirectorySeparatorChar + "SetCreationTimeUtcArgumentOutOfRangeException1";
+//			string path = tmpFolder + Path.DirectorySeparatorChar + "SetCreationTimeUtcArgumentOutOfRangeException1";
 //			DeleteFile (path);
 //			FileStream stream = null;
 //			try {
@@ -1951,7 +1954,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetCreationTimeUtc_FileLock ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "SetCreationTimeUtcIOException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "SetCreationTimeUtcIOException1";
 			DeleteFile (path);
 			FileStream stream = null;
 			try {
@@ -2042,7 +2045,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetLastAccessTime_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastAccessTimeFileNotFoundException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastAccessTimeFileNotFoundException1";
 			DeleteFile (path);
 
 			try {
@@ -2060,7 +2063,7 @@ namespace MonoTests.System.IO
 //		[ExpectedException(typeof (ArgumentOutOfRangeException))]
 //		public void SetLastAccessTimeArgumentOutOfRangeException1 ()
 //		{
-//			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastTimeArgumentOutOfRangeException1";
+//			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastTimeArgumentOutOfRangeException1";
 //			DeleteFile (path);
 //			FileStream stream = null;
 //			try {
@@ -2077,7 +2080,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetLastAccessTime_FileLock ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "LastAccessIOException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "LastAccessIOException1";
 			DeleteFile (path);
 			FileStream stream = null;
 			try {
@@ -2166,7 +2169,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetLastAccessTimeUtc_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastAccessTimeUtcFileNotFoundException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastAccessTimeUtcFileNotFoundException1";
 			DeleteFile (path);
 
 			try {
@@ -2184,7 +2187,7 @@ namespace MonoTests.System.IO
 //		[ExpectedException(typeof (ArgumentOutOfRangeException))]
 //		public void SetLastAccessTimeUtcArgumentOutOfRangeException1 ()
 //		{
-//			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastAccessTimeUtcArgumentOutOfRangeException1";
+//			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastAccessTimeUtcArgumentOutOfRangeException1";
 //			DeleteFile (path);
 //			FileStream stream = null;
 //			try {
@@ -2201,7 +2204,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetLastAccessTimeUtc_FileLock ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastAccessTimeUtcIOException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastAccessTimeUtcIOException1";
 			DeleteFile (path);
 			FileStream stream = null;
 			try {
@@ -2292,7 +2295,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetLastWriteTime_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeFileNotFoundException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeFileNotFoundException1";
 			DeleteFile (path);
 
 			try {
@@ -2310,7 +2313,7 @@ namespace MonoTests.System.IO
 //		[ExpectedException(typeof (ArgumentOutOfRangeException))]
 //		public void SetLastWriteTimeArgumentOutOfRangeException1 ()
 //		{
-//			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeArgumentOutOfRangeException1";
+//			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeArgumentOutOfRangeException1";
 //			DeleteFile (path);
 //			FileStream stream = null;
 //			try {
@@ -2327,7 +2330,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetLastWriteTime_FileLock ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "LastWriteTimeIOException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "LastWriteTimeIOException1";
 			DeleteFile (path);
 			FileStream stream = null;
 			try {
@@ -2416,7 +2419,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetLastWriteTimeUtc_Path_DoesNotExist ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeUtcFileNotFoundException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeUtcFileNotFoundException1";
 			DeleteFile (path);
 
 			try {
@@ -2434,7 +2437,7 @@ namespace MonoTests.System.IO
 //		[ExpectedException(typeof (ArgumentOutOfRangeException))]
 //		public void SetLastWriteTimeUtcArgumentOutOfRangeException1 ()
 //		{
-//			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeUtcArgumentOutOfRangeException1";
+//			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeUtcArgumentOutOfRangeException1";
 //			DeleteFile (path);
 //			FileStream stream = null;
 //			try {
@@ -2451,7 +2454,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void SetLastWriteTimeUtc_FileLock ()
 		{
-			string path = TempFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeUtcIOException1";
+			string path = tmpFolder + Path.DirectorySeparatorChar + "SetLastWriteTimeUtcIOException1";
 			DeleteFile (path);
 			FileStream stream = null;
 			try {
@@ -2580,7 +2583,7 @@ namespace MonoTests.System.IO
 		[Test]
 		public void ReplaceTest ()
 		{
-			string tmp = Path.Combine (TempFolder, "ReplaceTest");
+			string tmp = Path.Combine (tmpFolder, "ReplaceTest");
 			Directory.CreateDirectory (tmp);
 			string origFile = Path.Combine (tmp, "origFile");
 			string replaceFile = Path.Combine (tmp, "replaceFile");
diff --git a/mcs/class/corlib/Test/System.IO/StreamReaderTest.cs b/mcs/class/corlib/Test/System.IO/StreamReaderTest.cs
index eb29cfa9e4b..f916c57a6ac 100644
--- a/mcs/class/corlib/Test/System.IO/StreamReaderTest.cs
+++ b/mcs/class/corlib/Test/System.IO/StreamReaderTest.cs
@@ -18,15 +18,20 @@ namespace MonoTests.System.IO
 [TestFixture]
 public class StreamReaderTest
 {
-	static string TempFolder = Path.Combine (Path.GetTempPath (), "MonoTests.System.IO.Tests");
-	private string _codeFileName = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
+	private string _tmpFolder;
+	private string _codeFileName;
 	private const string TestString = "Hello World!";
 
 	[SetUp]
 	public void SetUp ()
 	{	
-		if (!Directory.Exists (TempFolder))
-			Directory.CreateDirectory (TempFolder);
+		_tmpFolder = Path.GetTempFileName ();
+		if (File.Exists (_tmpFolder))
+			File.Delete (_tmpFolder);
+		_codeFileName = _tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
+
+		if (!Directory.Exists (_tmpFolder))
+			Directory.CreateDirectory (_tmpFolder);
 		
 		if (!File.Exists (_codeFileName))
 			File.Create (_codeFileName).Close ();
@@ -35,8 +40,8 @@ public class StreamReaderTest
 	[TearDown]
 	public void TearDown ()
 	{
-		if (Directory.Exists (TempFolder))
-			Directory.Delete (TempFolder, true);
+		if (Directory.Exists (_tmpFolder))
+			Directory.Delete (_tmpFolder, true);
 	}
 
 
@@ -245,7 +250,7 @@ public class StreamReaderTest
 		{
 			bool errorThrown = false;
 			try {
-				new StreamReader(TempFolder + "/nonexistentfile", false);
+				new StreamReader(_tmpFolder + "/nonexistentfile", false);
 			} catch (FileNotFoundException) {
 				errorThrown = true;
 			} catch (Exception e) {
@@ -256,7 +261,7 @@ public class StreamReaderTest
 		{
 			bool errorThrown = false;
 			try {
-				new StreamReader(TempFolder + "/nonexistentdir/file", false);
+				new StreamReader(_tmpFolder + "/nonexistentdir/file", false);
 			} catch (DirectoryNotFoundException) {
 				errorThrown = true;
 			} catch (Exception e) {
@@ -310,7 +315,7 @@ public class StreamReaderTest
 		{
 			bool errorThrown = false;
 			try {
-				new StreamReader(TempFolder + "/nonexistentfile", true);
+				new StreamReader(_tmpFolder + "/nonexistentfile", true);
 			} catch (FileNotFoundException) {
 				errorThrown = true;
 			} catch (Exception e) {
@@ -321,7 +326,7 @@ public class StreamReaderTest
 		{
 			bool errorThrown = false;
 			try {
-				new StreamReader(TempFolder + "/nonexistentdir/file", true);
+				new StreamReader(_tmpFolder + "/nonexistentdir/file", true);
 			} catch (DirectoryNotFoundException) {
 				errorThrown = true;
 			} catch (Exception e) {
diff --git a/mcs/class/corlib/Test/System.IO/StreamWriterTest.cs b/mcs/class/corlib/Test/System.IO/StreamWriterTest.cs
index a0afe231788..9e47fd6921d 100644
--- a/mcs/class/corlib/Test/System.IO/StreamWriterTest.cs
+++ b/mcs/class/corlib/Test/System.IO/StreamWriterTest.cs
@@ -95,16 +95,23 @@ namespace MonoTests.System.IO
 			}
 		}
 
-	static string TempFolder = Path.Combine (Path.GetTempPath (), "MonoTests.System.IO.Tests");
-	private string _codeFileName = TempFolder + Path.DirectorySeparatorChar + "AFile.txt";
-	private string _thisCodeFileName = TempFolder + Path.DirectorySeparatorChar + "StreamWriterTest.temp";
+	private string _tmpFolder;
+	private string _codeFileName;
+	private string _thisCodeFileName;
 
 	[SetUp]
 	public void SetUp ()
 	{
-		if (Directory.Exists (TempFolder))
-			Directory.Delete (TempFolder, true);
-		Directory.CreateDirectory (TempFolder);
+		_tmpFolder = Path.GetTempFileName ();
+		if (File.Exists (_tmpFolder))
+			File.Delete (_tmpFolder);
+
+		_codeFileName = _tmpFolder + Path.DirectorySeparatorChar + "AFile.txt";
+		_thisCodeFileName = _tmpFolder + Path.DirectorySeparatorChar + "StreamWriterTest.temp";
+
+		if (Directory.Exists (_tmpFolder))
+			Directory.Delete (_tmpFolder, true);
+		Directory.CreateDirectory (_tmpFolder);
 
 		if (!File.Exists (_thisCodeFileName)) 
 			File.Create (_thisCodeFileName).Close ();
@@ -113,8 +120,8 @@ namespace MonoTests.System.IO
 	[TearDown]
 	public void TearDown ()
 	{
-		if (Directory.Exists (TempFolder))
-			Directory.Delete (TempFolder, true);
+		if (Directory.Exists (_tmpFolder))
+			Directory.Delete (_tmpFolder, true);
 	}
 
 	[Test] // .ctor (Stream)
@@ -182,7 +189,7 @@ namespace MonoTests.System.IO
 	[Test] // .ctor (String)
 	public void Constructor2_Path_DirectoryNotFound ()
 	{
-		Directory.Delete (TempFolder, true);
+		Directory.Delete (_tmpFolder, true);
 
 		try {
 			new StreamWriter (_codeFileName);
@@ -192,7 +199,7 @@ namespace MonoTests.System.IO
 			Assert.AreEqual (typeof (DirectoryNotFoundException), ex.GetType (), "#2");
 			Assert.IsNull (ex.InnerException, "#3");
 			Assert.IsNotNull (ex.Message, "#4");
-			Assert.IsTrue (ex.Message.IndexOf (TempFolder) != -1, "#5");
+			Assert.IsTrue (ex.Message.IndexOf (_tmpFolder) != -1, "#5");
 		}
 	}
 
@@ -328,7 +335,7 @@ namespace MonoTests.System.IO
 	[Test] // .ctor (String, Boolean)
 	public void Constructor4_Path_DirectoryNotFound ()
 	{
-		Directory.Delete (TempFolder, true);
+		Directory.Delete (_tmpFolder, true);
 
 		try {
 			new StreamWriter (_codeFileName, false);
@@ -338,7 +345,7 @@ namespace MonoTests.System.IO
 			Assert.AreEqual (typeof (DirectoryNotFoundException), ex.GetType (), "#A2");
 			Assert.IsNull (ex.InnerException, "#A3");
 			Assert.IsNotNull (ex.Message, "#A4");
-			Assert.IsTrue (ex.Message.IndexOf (TempFolder) != -1, "#A5");
+			Assert.IsTrue (ex.Message.IndexOf (_tmpFolder) != -1, "#A5");
 		}
 
 		try {
@@ -349,7 +356,7 @@ namespace MonoTests.System.IO
 			Assert.AreEqual (typeof (DirectoryNotFoundException), ex.GetType (), "#B2");
 			Assert.IsNull (ex.InnerException, "#B3");
 			Assert.IsNotNull (ex.Message, "#B4");
-			Assert.IsTrue (ex.Message.IndexOf (TempFolder) != -1, "#B5");
+			Assert.IsTrue (ex.Message.IndexOf (_tmpFolder) != -1, "#B5");
 		}
 	}
 
@@ -579,7 +586,7 @@ namespace MonoTests.System.IO
 	[Test] // .ctor (String, Boolean, Encoding)
 	public void Constructor6_Path_DirectoryNotFound ()
 	{
-		Directory.Delete (TempFolder, true);
+		Directory.Delete (_tmpFolder, true);
 
 		try {
 			new StreamWriter (_codeFileName, false, Encoding.UTF8);
@@ -589,7 +596,7 @@ namespace MonoTests.System.IO
 			Assert.AreEqual (typeof (DirectoryNotFoundException), ex.GetType (), "#A2");
 			Assert.IsNull (ex.InnerException, "#A3");
 			Assert.IsNotNull (ex.Message, "#A4");
-			Assert.IsTrue (ex.Message.IndexOf (TempFolder) != -1, "#A5");
+			Assert.IsTrue (ex.Message.IndexOf (_tmpFolder) != -1, "#A5");
 		}
 
 		try {
@@ -600,7 +607,7 @@ namespace MonoTests.System.IO
 			Assert.AreEqual (typeof (DirectoryNotFoundException), ex.GetType (), "#B2");
 			Assert.IsNull (ex.InnerException, "#B3");
 			Assert.IsNotNull (ex.Message, "#B4");
-			Assert.IsTrue (ex.Message.IndexOf (TempFolder) != -1, "#B5");
+			Assert.IsTrue (ex.Message.IndexOf (_tmpFolder) != -1, "#B5");
 		}
 	}
 
@@ -759,7 +766,7 @@ namespace MonoTests.System.IO
 	[Test] // .ctor (String, Boolean, Encoding, Int32)
 	public void Constructor7_Path_DirectoryNotFound ()
 	{
-		Directory.Delete (TempFolder, true);
+		Directory.Delete (_tmpFolder, true);
 
 		try {
 			new StreamWriter (_codeFileName, false, Encoding.UTF8, 10);
@@ -769,7 +776,7 @@ namespace MonoTests.System.IO
 			Assert.AreEqual (typeof (DirectoryNotFoundException), ex.GetType (), "#A2");
 			Assert.IsNull (ex.InnerException, "#A3");
 			Assert.IsNotNull (ex.Message, "#A4");
-			Assert.IsTrue (ex.Message.IndexOf (TempFolder) != -1, "#A5");
+			Assert.IsTrue (ex.Message.IndexOf (_tmpFolder) != -1, "#A5");
 		}
 
 		try {
@@ -780,7 +787,7 @@ namespace MonoTests.System.IO
 			Assert.AreEqual (typeof (DirectoryNotFoundException), ex.GetType (), "#B2");
 			Assert.IsNull (ex.InnerException, "#B3");
 			Assert.IsNotNull (ex.Message, "#B4");
-			Assert.IsTrue (ex.Message.IndexOf (TempFolder) != -1, "#B5");
+			Assert.IsTrue (ex.Message.IndexOf (_tmpFolder) != -1, "#B5");
 		}
 	}