Make ContextDirectoryManager responsible for scanning directory contents.

pkg/analysis_server/lib/src/context_directory_manager.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library context.directory.manager;
 
 import 'package:analysis_server/src/resource.dart';
+import 'package:analyzer/src/generated/engine.dart';
+import 'package:analyzer/src/generated/source.dart';
 
 /**
  * Class that maintains a mapping from included/excluded paths to a set of
  * folders that should correspond to analysis contexts.
  */
 abstract class ContextDirectoryManager {
   /**
    * The set of included folders in the most recent successful call to
    * [setRoots].
    */
@@ skipping 35 matching lines @@
     Set<Folder> excludedFolders = new Set<Folder>();
     // diff
     Set<Folder> newFolders = includedFolders.difference(currentFolders);
     Set<Folder> oldFolders = currentFolders.difference(includedFolders);
     // remove old contexts
     for (Folder folder in oldFolders) {
       // TODO(scheglov) implement
     }
     // add new contexts
     for (Folder folder in newFolders) {
-      addContext(folder);
+      File pubspecFile = folder.getChild('pubspec.yaml');
+      addContext(folder, pubspecFile.exists ? pubspecFile : null);
+      ChangeSet changeSet = new ChangeSet();
+      _addSourceFiles(changeSet, folder);
+      applyChangesToContext(folder, changeSet);
     }
     currentFolders = new Set<Folder>.from(includedFolders);
   }
 
   /**
-   * Called when a new context needs to be created.
+   * Resursively adds all Dart and HTML files to the [changeSet].
    */
-  void addContext(Folder folder);
+  static void _addSourceFiles(ChangeSet changeSet, Folder folder) {
+    List<Resource> children = folder.getChildren();
+    for (Resource child in children) {
+      if (child is File) {
+        String fileName = child.shortName;
+        if (AnalysisEngine.isDartFileName(fileName)
+            || AnalysisEngine.isHtmlFileName(fileName)) {
+          Source source = child.createSource(UriKind.FILE_URI);
+          changeSet.addedSource(source);
+        }
+      } else if (child is Folder) {
+        _addSourceFiles(changeSet, child);
+      }
+    }
+  }
+
+  /**
+   * Called when a new context needs to be created.  If the context is
+   * associated with a pubspec file, that file is passed in [pubspecFile];
+   * otherwise it is null.
+   */
+  void addContext(Folder folder, File pubspecFile);
+
+  /**
+   * Called when the set of files associated with a context have changed (or
+   * some of those files have been modified).  [changeSet] is the set of
+   * changes that need to be applied to the context.
+   */
+  void applyChangesToContext(Folder contextFolder, ChangeSet changeSet);
 }