Fix file recursion overflow problems

src/PowerShellEditorServices/Utility/Logging.cs

@@ -78,6 +78,21 @@ void WriteException(
             [CallerMemberName] string callerName = null,
             [CallerFilePath] string callerSourceFile = null,
             [CallerLineNumber] int callerLineNumber = 0);
+
+        /// <summary>
+        /// Log an exception that has been handled cleanly or is otherwise not expected to cause problems in the logs.
+        /// </summary>
+        /// <param name="errorMessage">The error message of the exception to be logged.</param>
+        /// <param name="exception">The exception itself that has been thrown.</param>
+        /// <param name="callerName">The name of the method in which the ILogger is being called.</param>
+        /// <param name="callerSourceFile">The name of the source file in which the ILogger is being called.</param>
+        /// <param name="callerLineNumber">The line number in the file where the ILogger is being called.</param>
+        void WriteHandledException(
+            string errorMessage,
+            Exception exception,
+            [CallerMemberName] string callerName = null,
+            [CallerFilePath] string callerSourceFile = null,
+            [CallerLineNumber] int callerLineNumber = 0);
     }
 
 

src/PowerShellEditorServices/Utility/PsesLogger.cs

@@ -11,11 +11,22 @@ namespace Microsoft.PowerShell.EditorServices.Utility
     /// </summary>
     public class PsesLogger : ILogger
     {
+        /// <summary>
+        /// The standard log template for all log entries.
+        /// </summary>
+        private static readonly string s_logMessageTemplate =
+            "[{LogLevelName:l}] tid:{ThreadId} in '{CallerName:l}' {CallerSourceFile:l} (line {CallerLineNumber}):{IndentedLogMsg:l}";
+
         /// <summary>
         /// The name of the ERROR log level.
         /// </summary>
         private static readonly string ErrorLevelName = LogLevel.Error.ToString().ToUpper();
 
+        /// <summary>
+        /// The name of the WARNING log level.
+        /// </summary>
+        private static readonly string WarningLevelName = LogLevel.Warning.ToString().ToUpper();
+
         /// <summary>
         /// The internal Serilog logger to log to.
         /// </summary>
@@ -57,25 +68,22 @@ public void Write(
 
             int threadId = Thread.CurrentThread.ManagedThreadId;
 
-            string messageTemplate = 
-                "[{LogLevelName:l}] tid:{threadId} in '{CallerName:l}' {CallerSourceFile:l}:{CallerLineNumber}:{IndentedLogMsg:l}";
-
             switch (logLevel)
             {
                 case LogLevel.Diagnostic:
-                    _logger.Verbose(messageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
+                    _logger.Verbose(s_logMessageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
                     return;
                 case LogLevel.Verbose:
-                    _logger.Debug(messageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
+                    _logger.Debug(s_logMessageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
                     return;
                 case LogLevel.Normal:
-                    _logger.Information(messageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
+                    _logger.Information(s_logMessageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
                     return;
                 case LogLevel.Warning:
-                    _logger.Warning(messageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
+                    _logger.Warning(s_logMessageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
                     return;
                 case LogLevel.Error:
-                    _logger.Error(messageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
+                    _logger.Error(s_logMessageTemplate, logLevelName, threadId, callerName, callerSourceFile, callerLineNumber, indentedLogMsg);
                     return;
             }
         }
@@ -95,10 +103,27 @@ public void WriteException(
             [CallerFilePath] string callerSourceFile = null,
             [CallerLineNumber] int callerLineNumber = 0)
         {
-            string indentedException = IndentMsg(exception.ToString());
+            string body = IndentExceptionMessage("Exception", errorMessage, exception);
+            Write(LogLevel.Error, body, callerName, callerSourceFile, callerLineNumber);
+        }
 
-            _logger.Error("[{ErrorLevelName:l}] {CallerSourceFile:l}: In method '{CallerName:l}', line {CallerLineNumber}: {ErrorMessage:l}{IndentedException:l}",
-                ErrorLevelName, callerSourceFile, callerName, callerLineNumber, errorMessage, indentedException);
+        /// <summary>
+        /// Log an exception that has been handled cleanly or is otherwise not expected to cause problems in the logs.
+        /// </summary>
+        /// <param name="errorMessage">The error message of the exception to be logged.</param>
+        /// <param name="exception">The exception itself that has been thrown.</param>
+        /// <param name="callerName">The name of the method in which the ILogger is being called.</param>
+        /// <param name="callerSourceFile">The name of the source file in which the ILogger is being called.</param>
+        /// <param name="callerLineNumber">The line number in the file where the ILogger is being called.</param>
+        public void WriteHandledException(
+            string errorMessage,
+            Exception exception,
+            [CallerMemberName] string callerName = null,
+            [CallerFilePath] string callerSourceFile = null,
+            [CallerLineNumber] int callerLineNumber = 0)
+        {
+            string body = IndentExceptionMessage("Handled exception", errorMessage, exception);
+            Write(LogLevel.Warning, body, callerName, callerSourceFile, callerLineNumber);
         }
 
         /// <summary>
@@ -108,13 +133,36 @@ public void WriteException(
         /// <returns>The indented log message string.</returns>
         private static string IndentMsg(string logMessage)
         {
-            return new StringBuilder(logMessage)
+            return IndentMsg(new StringBuilder(logMessage));
+        }
+
+        /// <summary>
+        /// Utility function to indent a log message by one level.
+        /// </summary>
+        /// <param name="logMessageBuilder">Log message string builder to transform.</param>
+        /// <returns>The indented log message string.</returns>
+        private static string IndentMsg(StringBuilder logMessageBuilder)
+        {
+            return logMessageBuilder
                 .Replace(Environment.NewLine, s_indentedPrefix)
                 .Insert(0, s_indentedPrefix)
                 .AppendLine()
                 .ToString();
         }
 
+        private static string IndentExceptionMessage(
+            string messagePrelude,
+            string errorMessage,
+            Exception exception)
+        {
+            var sb = new StringBuilder()
+                .Append(messagePrelude).Append(": ").Append(errorMessage).Append(Environment.NewLine)
+                .Append(Environment.NewLine)
+                .Append(exception.ToString());
+
+            return IndentMsg(sb);
+        }
+
         /// <summary>
         /// A newline followed by a single indentation prefix.
         /// </summary>

src/PowerShellEditorServices/Workspace/Workspace.cs

@@ -22,6 +22,13 @@ public class Workspace
     {
         #region Private Fields
 
+        private static readonly string[] s_psFilePatterns = new []
+        {
+            "*.ps1",
+            "*.psm1",
+            "*.psd1"
+        };
+
         private ILogger logger;
         private Version powerShellVersion;
         private Dictionary<string, ScriptFile> workspaceFiles = new Dictionary<string, ScriptFile>();
@@ -292,67 +299,106 @@ public IEnumerable<string> EnumeratePSFiles()
 
         #region Private Methods
 
+        /// <summary>
+        /// Find PowerShell files recursively down from a given directory path.
+        /// Currently returns files in depth-first order.
+        /// Directory.GetFiles(folderPath, pattern, SearchOption.AllDirectories) would provide this,
+        /// but a cycle in the filesystem will cause that to enter an infinite loop.
+        /// </summary>
+        /// <param name="folderPath">The absolute path of the base folder to search.</param>
+        /// <returns>
+        /// All PowerShell files in the recursive directory hierarchy under the given base directory, up to 64 directories deep.
+        /// </returns>
         private IEnumerable<string> RecursivelyEnumerateFiles(string folderPath)
         {
-            var foundFiles = Enumerable.Empty<string>();
-            var patterns = new string[] { @"*.ps1", @"*.psm1", @"*.psd1" };
+            var foundFiles = new List<string>();
+            var dirStack = new Stack<string>();
 
-            try
+            // Kick the search off with the base directory
+            dirStack.Push(folderPath);
+
+            const int recursionDepthLimit = 64;
+            while (dirStack.Any())
             {
-                IEnumerable<string> subDirs = Directory.GetDirectories(folderPath);
-                foreach (string dir in subDirs)
+                string currDir = dirStack.Pop();
+
+                // Look for any PowerShell files in the current directory
+                foreach (string pattern in s_psFilePatterns)
                 {
-                    foundFiles =
-                        foundFiles.Concat(
-                            RecursivelyEnumerateFiles(dir));
+                    string[] psFiles;
+                    try
+                    {
+                        psFiles = Directory.GetFiles(currDir, pattern, SearchOption.TopDirectoryOnly);
+                    }
+                    catch (DirectoryNotFoundException e)
+                    {
+                        this.logger.WriteHandledException(
+                            $"Could not enumerate files in the path '{currDir}' due to it being an invalid path",
+                            e);
+
+                        continue;
+                    }
+                    catch (PathTooLongException e)
+                    {
+                        this.logger.WriteHandledException(
+                            $"Could not enumerate files in the path '{currDir}' due to the path being too long",
+                            e);
+
+                        continue;
+                    }
+                    catch (Exception e) when (e is SecurityException || e is UnauthorizedAccessException)
+                    {
+                        this.logger.WriteHandledException(
+                            $"Could not enumerate files in the path '{currDir}' due to the path not being accessible",
+                            e);
+
+                        continue;
+                    }
+
+                    foundFiles.AddRange(psFiles);
                 }
-            }
-            catch (DirectoryNotFoundException e)
-            {
-                this.logger.WriteException(
-                    $"Could not enumerate files in the path '{folderPath}' due to it being an invalid path",
-                    e);
-            }
-            catch (PathTooLongException e)
-            {
-                this.logger.WriteException(
-                    $"Could not enumerate files in the path '{folderPath}' due to the path being too long",
-                    e);
-            }
-            catch (Exception e) when (e is SecurityException || e is UnauthorizedAccessException)
-            {
-                this.logger.WriteException(
-                    $"Could not enumerate files in the path '{folderPath}' due to the path not being accessible",
-                    e);
-            }
 
-            foreach (var pattern in patterns)
-            {
+                // Prevent unbounded recursion here
+                // If we get too deep, keep processing but go no deeper
+                if (dirStack.Count >= recursionDepthLimit)
+                {
+                    continue;
+                }
+
+                // Add the recursive directories to search next
+                string[] subDirs;
                 try
                 {
-                    foundFiles =
-                        foundFiles.Concat(
-                            Directory.GetFiles(
-                                folderPath,
-                                pattern));
+                    subDirs = Directory.GetDirectories(currDir);
                 }
                 catch (DirectoryNotFoundException e)
                 {
-                    this.logger.WriteException(
-                        $"Could not enumerate files in the path '{folderPath}' due to a path being an invalid path",
+                    this.logger.WriteHandledException(
+                        $"Could not enumerate directories in the path '{currDir}' due to it being an invalid path",
                         e);
+
+                    continue;
                 }
                 catch (PathTooLongException e)
                 {
-                    this.logger.WriteException(
-                        $"Could not enumerate files in the path '{folderPath}' due to a path being too long",
+                    this.logger.WriteHandledException(
+                        $"Could not enumerate directories in the path '{currDir}' due to the path being too long",
                         e);
+
+                    continue;
                 }
                 catch (Exception e) when (e is SecurityException || e is UnauthorizedAccessException)
                 {
-                    this.logger.WriteException(
-                        $"Could not enumerate files in the path '{folderPath}' due to a path not being accessible",
+                    this.logger.WriteHandledException(
+                        $"Could not enumerate directories in the path '{currDir}' due to the path not being accessible",
                         e);
+
+                    continue;
+                }
+
+                foreach (string subDir in subDirs)
+                {
+                    dirStack.Push(subDir);
                 }
             }