Merge pull request #151 from Microsoft/version

Fix frequent module reloading + add version banner

Author: Mikhail Arkhipov

src/LanguageServer/Impl/Implementation/Server.cs

@@ -377,11 +377,7 @@ private async Task DoInitializeAsync(InitializeParams @params, CancellationToken
             }
             _displayTextBuilder = DocumentationBuilder.Create(DisplayOptions);
 
-            if (string.IsNullOrEmpty(Analyzer.InterpreterFactory?.Configuration?.InterpreterPath)) {
-                LogMessage(MessageType._General, "Initializing for generic interpreter");
-            } else {
-                LogMessage(MessageType._General, $"Initializing for {Analyzer.InterpreterFactory.Configuration.InterpreterPath}");
-            }
+            DisplayStartupInfo();
 
             if (@params.rootUri != null) {
                 _rootDir = @params.rootUri.ToAbsolutePath();
@@ -395,6 +391,14 @@ private async Task DoInitializeAsync(InitializeParams @params, CancellationToken
             Analyzer.Interpreter.ModuleNamesChanged += Interpreter_ModuleNamesChanged;
         }
 
+        private void DisplayStartupInfo() {
+            LogMessage(MessageType._General, Resources.LanguageServerVersion.FormatInvariant(Assembly.GetExecutingAssembly().GetName().Version));
+            LogMessage(MessageType._General,
+                string.IsNullOrEmpty(Analyzer.InterpreterFactory?.Configuration?.InterpreterPath)
+                ? Resources.InitializingForGenericInterpreter
+                : Resources.InitializingForPythonInterpreter.FormatInvariant(Analyzer.InterpreterFactory.Configuration.InterpreterPath));
+        }
+
         private void Interpreter_ModuleNamesChanged(object sender, EventArgs e) {
             Analyzer.Modules.ReInit();
             foreach (var entry in Analyzer.ModulesByFilename) {
@@ -433,7 +437,7 @@ private async Task<PythonAnalyzer> CreateAnalyzer(PythonInitializationOptions.In
 
             var interp = factory.CreateInterpreter();
             if (interp == null) {
-                throw new InvalidOperationException("Failed to create interpreter");
+                throw new InvalidOperationException(Resources.Error_FailedToCreateInterpreter);
             }
 
             LogMessage(MessageType.Info, $"Created {interp.GetType().FullName} instance from {factory.GetType().FullName}");

src/LanguageServer/Impl/PathsWatcher.cs

@@ -33,41 +33,40 @@ internal sealed class PathsWatcher : IDisposable {
 
         public PathsWatcher(string[] paths, Action onChanged, ILogger log) {
             _log = log;
-            if (paths?.Length == 0) {
+            paths = paths != null ? paths.Where(p => Path.IsPathRooted(p)).ToArray() : Array.Empty<string>();
+            if (paths.Length == 0) {
                 return;
             }
 
             _onChanged = onChanged;
 
-            var list = new List<FileSystemWatcher>();
             var reduced = ReduceToCommonRoots(paths);
             foreach (var p in reduced) {
                 try {
                     if (!Directory.Exists(p)) {
                         continue;
                     }
-                } catch(IOException ex) {
+                } catch (IOException ex) {
                     _log.TraceMessage($"Unable to access directory {p}, exception {ex.Message}");
                     continue;
                 }
 
                 try {
                     var fsw = new System.IO.FileSystemWatcher(p) {
                         IncludeSubdirectories = true,
-                        EnableRaisingEvents = true
+                        EnableRaisingEvents = true,
+                        NotifyFilter = NotifyFilters.FileName | NotifyFilters.DirectoryName
                     };
 
-                    fsw.Changed += OnChanged;
                     fsw.Created += OnChanged;
                     fsw.Deleted += OnChanged;
 
                     _disposableBag
-                        .Add(() => fsw.Changed -= OnChanged)
                         .Add(() => fsw.Created -= OnChanged)
                         .Add(() => fsw.Deleted -= OnChanged)
                         .Add(() => fsw.EnableRaisingEvents = false)
                         .Add(fsw);
-                } catch(ArgumentException ex) {
+                } catch (ArgumentException ex) {
                     _log.TraceMessage($"Unable to create file watcher for {p}, exception {ex.Message}");
                 }
             }
@@ -84,9 +83,9 @@ private void OnChanged(object sender, FileSystemEventArgs e) {
 
         private void TimerProc(object o) {
             lock (_lock) {
-                if (!_changedSinceLastTick && _throttleTimer != null) {
+                if (_changedSinceLastTick) {
                     ThreadPool.QueueUserWorkItem(_ => _onChanged());
-                    _throttleTimer.Dispose();
+                    _throttleTimer?.Dispose();
                     _throttleTimer = null;
                 }
                 _changedSinceLastTick = false;

src/LanguageServer/Impl/Resources.Designer.cs

@@ -123,6 +123,18 @@
   <data name="AnalysisProgress_SingleItemRemaining" xml:space="preserve">
     <value>Analyzing workspace, 1 item remaining...</value>
   </data>
+  <data name="Error_FailedToCreateInterpreter" xml:space="preserve">
+    <value>Failed to create interpreter</value>
+  </data>
+  <data name="InitializingForGenericInterpreter" xml:space="preserve">
+    <value>Initializing for generic interpreter</value>
+  </data>
+  <data name="InitializingForPythonInterpreter" xml:space="preserve">
+    <value>Initializing for {0}</value>
+  </data>
+  <data name="LanguageServerVersion" xml:space="preserve">
+    <value>Microsoft Python Language Server version {0}</value>
+  </data>
   <data name="RenameVariable_CannotRename" xml:space="preserve">
     <value>Cannot rename</value>
   </data>