Fix couple of bugs (microsoft#566)

* Handle enableUnresolvedImportWarning and enableUseBeforeDefWarning options in PLS

* Fix nuspec folder

* Fix PTVS issue #5026: Imported packages remain unresolved once a new environment is finished being created

Author: AlexanderSher

src/Analysis/Engine/Impl/DependencyResolution/PathResolverSnapshot.cs

@@ -69,6 +69,7 @@ private PathResolverSnapshot(PythonLanguageVersion pythonLanguageVersion, string
 
         public IEnumerable<string> GetAllModuleNames() => GetModuleNames(_roots.Prepend(_nonRooted).Append(_builtins));
         public IEnumerable<string> GetInterpreterModuleNames() => GetModuleNames(_roots.Skip(_userRootsCount).Append(_builtins));
+        public IEnumerable<string> GetRootPaths() => _roots.Select(r => r.Name);
 
         private static IEnumerable<string> GetModuleNames(IEnumerable<Node> roots) => roots
             .SelectMany(r => r.TraverseBreadthFirst(n => n.IsModule ? Enumerable.Empty<Node>() : n.Children))

src/Analysis/Engine/Impl/PythonAnalyzer.cs

@@ -68,7 +68,7 @@ public partial class PythonAnalyzer : IPythonAnalyzer, IDisposable {
         public static async Task<PythonAnalyzer> CreateAsync(IPythonInterpreterFactory factory, CancellationToken token = default) {
             var analyzer = new PythonAnalyzer(factory);
             try {
-                await analyzer.ReloadModulesAsync(token).ConfigureAwait(false);
+                await analyzer.ReloadModulesAsync(false, token).ConfigureAwait(false);
             } catch(Exception) {
                 analyzer.Dispose();
                 throw;
@@ -140,7 +140,9 @@ private void ReloadModulePaths(in IEnumerable<string> rootPaths) {
         /// This method should be called on the analysis thread and is usually invoked
         /// when the interpreter signals that it's modules have changed.
         /// </summary>
-        public async Task ReloadModulesAsync(CancellationToken token = default) {
+        public Task ReloadModulesAsync(CancellationToken token = default) => ReloadModulesAsync(true, token);
+
+        private async Task ReloadModulesAsync(bool reScanRoots, CancellationToken token) {
             if (!_reloadLock.Wait(0)) {
                 // If we don't lock immediately, wait for the current reload to
                 // complete and then return.
@@ -156,6 +158,11 @@ public async Task ReloadModulesAsync(CancellationToken token = default) {
                 InterpreterFactory.NotifyImportNamesChanged();
                 // Now initialize the interpreter
                 Interpreter.Initialize(this);
+                // Rescan roots for modules if requested
+                if (reScanRoots) {
+                    ReloadModulePaths(CurrentPathResolver.GetRootPaths());
+                }
+
                 // Reload importable modules
                 Modules.Reload();
                 // Load known types from the selected interpreter
@@ -760,7 +767,7 @@ public void AnalyzeQueuedEntries(CancellationToken cancel) {
 
             if (_builtinModule == null) {
                 Debug.Fail("Used analyzer without reloading modules");
-                ReloadModulesAsync(cancel).WaitAndUnwrapExceptions();
+                ReloadModulesAsync(true, cancel).WaitAndUnwrapExceptions();
             }
 
             var ddg = new DDG();

src/PTVS/Microsoft.PythonTools.Analyzer/Impl/python-language-server-ptvs.nuspec

@@ -23,7 +23,7 @@
     <file src="Microsoft.PythonTools.Analyzer.exe" target="lib/vs16" />
     <file src="Microsoft.PythonTools.Analyzer.exe.config" target="lib/vs16" />
     <file src="Microsoft.PythonTools.Analyzer.pdb" target="lib/vs16" />
-    <file src="Typeshed/**" target="lib/vs16/Typeshed" />
+    <file src="Typeshed/**" target="lib/vs16" />
     <file src="PythonScraper.py" target="lib/vs16" />
     <file src="BuiltinScraper.py" target="lib/vs16" />
     <file src="ExtensionScraper.py" target="lib/vs16" />