Fixes error in file deletion after test finish

Author: Christine Zhou

Tst/UnitTests/PCheckerLogGeneratorTests.cs

@@ -70,6 +70,7 @@ private void AssertLog(string generatedDir, string expectedDir)
         {
             Assert.Fail($"Test Failed \nMissing expected file in {generatedDir}: {file}");
         }
+        Console.WriteLine("Test Succeeded");
     }
 
     private static bool IsJsonContentIncluded(string generatedFilePath, string expectedFilePath)

Tst/UnitTests/TestAssertions.cs

@@ -1,5 +1,6 @@
 using System;
 using System.IO;
+using System.Threading;
 using NUnit.Framework;
 using UnitTests.Core;
 
@@ -26,14 +27,42 @@ public static void AssertTestCase(CompilerTestCase testCase)
         public static void SafeDeleteDirectory(DirectoryInfo toDelete)
         {
             var safeBase = new DirectoryInfo(Constants.SolutionDirectory);
+
             for (var scratch = toDelete; scratch.Parent != null; scratch = scratch.Parent)
             {
-                if (string.Compare(scratch.FullName, safeBase.FullName, StringComparison.InvariantCultureIgnoreCase) ==
-                    0)
+                if (string.Compare(scratch.FullName, safeBase.FullName, StringComparison.InvariantCultureIgnoreCase) == 0)
                 {
                     if (toDelete.Exists)
                     {
-                        toDelete.Delete(true);
+                        const int maxRetries = 5;
+                        const int delay = 200;
+
+                        for (int i = 0; i < maxRetries; i++)
+                        {
+                            try
+                            {
+                                toDelete.Delete(true);
+                                return;
+                            }
+                            catch (IOException)
+                            {
+                                if (i == maxRetries - 1)
+                                {
+                                    throw;
+                                }
+
+                                Thread.Sleep(delay);
+                            }
+                            catch (UnauthorizedAccessException)
+                            {
+                                if (i == maxRetries - 1)
+                                {
+                                    throw;
+                                }
+
+                                Thread.Sleep(delay);
+                            }
+                        }
                     }
 
                     return;