Update scan, changed and discard to handle "packages" and "pubspec.yaml"

editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/analysis/SavedContext.java

Index: editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/analysis/SavedContext.java
===================================================================
--- editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/analysis/SavedContext.java	(revision 11962)
+++ editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/analysis/SavedContext.java	(working copy)
@@ -15,9 +15,13 @@
 
 import com.google.dart.compiler.PackageLibraryManager;
 
+import static com.google.dart.tools.core.analysis.AnalysisUtility.equalsOrContains;
+
 import java.io.File;
+import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
+import java.util.Iterator;
 
 /**
  * Analysis of Dart source saved on disk
@@ -25,8 +29,8 @@
 public class SavedContext extends Context {
 
   /**
-   * A mapping of directories containing a "packages" to current package contexts. This should only
-   * be accessed on the background thread.
+   * A mapping of application directories (directories containing a "packages" directory) to current
+   * package contexts. This should only be accessed on the background thread.
    */
   private HashMap<File, PackageContext> packageContexts = new HashMap<File, PackageContext>();
 
@@ -34,16 +38,66 @@
     super(server, libraryManager);
   }
 
+  /**
+   * TESTING: Answer an array of directories for which a {@link PackageContext} has been defined
+   */
+  public File[] getApplicationDirectories() {
+    return packageContexts.keySet().toArray(new File[packageContexts.keySet().size()]);
+  }
+
   @Override
   public String toString() {
     return getClass().getSimpleName();
   }
 
-  void discardPackageContext(PackageContext context) {
-    packageContexts.remove(context.getApplicationDirectory());
+  /**
+   * Discard all package contexts in addition to all libraries without notifying any listeners about
+   * discarded libraries
+   */
+  @Override
+  void discardAllLibraries() {
+    packageContexts.clear();
+    super.discardAllLibraries();
   }
 
   /**
+   * If the specified file is a directory, then discard all libraries in that directory tree
+   * otherwise discard the specified library. In both cases, discard all libraries that directly or
+   * indirectly reference the discarded libraries.
+   * 
+   * @param rootFile the original file or directory to discard
+   * @return the collection of discarded libraries (not <code>null</code>, contains no
+   *         <code>null</code>s)
+   */
+  Collection<Library> discardLibraries(File rootFile) {
+    ArrayList<Library> discarded = new ArrayList<Library>(40);
+    discardLibraries(rootFile, discarded);
+    return discarded;
+  };
+
+  /**
+   * If the specified file is a directory, then discard all libraries and package contexts in that
+   * directory tree otherwise discard the specified library. In both cases, discard all libraries
+   * that directly or indirectly reference the discarded libraries.
+   * 
+   * @param rootFile the original file or directory to discard
+   * @param discarded the collection of discarded libraries and to which newly discarded libraries
+   *          should be added (not <code>null</code>, contains no <code>null</code>s)
+   */
+  @Override
+  void discardLibraries(File rootFile, ArrayList<Library> discarded) {
+    super.discardLibraries(rootFile, discarded);
+    Iterator<PackageContext> iter = packageContexts.values().iterator();
+    while (iter.hasNext()) {
+      PackageContext context = iter.next();
+      context.discardLibraries(rootFile, discarded);
+      if (equalsOrContains(rootFile, context.getApplicationDirectory())) {
+        iter.remove();
+      }
+    }
+  };
+
+  /**
    * Answer the package context for the specified application directory, creating and caching a new
    * one if one does not already exist.
    * 
@@ -58,8 +112,4 @@
     }
     return context;
   }
-
-  Collection<PackageContext> getPackageContexts() {
-    return packageContexts.values();
-  }
 }