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/DiscardTask.java

Index: editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/analysis/DiscardTask.java
===================================================================
--- editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/analysis/DiscardTask.java	(revision 11962)
+++ editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/analysis/DiscardTask.java	(working copy)
@@ -15,11 +15,7 @@
 
 import com.google.dart.tools.core.DartCore;
 
-import static com.google.dart.tools.core.analysis.AnalysisUtility.equalsOrContains;
-
 import java.io.File;
-import java.util.ArrayList;
-import java.util.Collection;
 
 /**
  * Remove package contexts, cached libraries, and any tasks related to analyzing those libraries
@@ -27,15 +23,11 @@
 class DiscardTask extends Task {
 
   private final AnalysisServer server;
-  private final SavedContext savedContext;
   private final File rootFile;
-  private final ArrayList<Library> discardedLibraries;
 
   public DiscardTask(AnalysisServer server, File file) {
     this.server = server;
-    this.savedContext = server.getSavedContext();
     this.rootFile = file;
-    this.discardedLibraries = new ArrayList<Library>();
   }
 
   @Override
@@ -50,95 +42,23 @@
 
   @Override
   public void perform() {
+    File file = rootFile;
 
-    // If this is a dart file, then discard the cached library
-    if (rootFile.isFile()
-        || (!rootFile.exists() && DartCore.isDartLikeFileName(rootFile.getName()))) {
-      for (PackageContext packageContext : savedContext.getPackageContexts()) {
-        discardLibrary(packageContext, rootFile);
-      }
-      discardLibrary(savedContext, rootFile);
+    // If a "packages" directory was discarded, then discard the application context
+    // The pubspec may have already been discarded, so only check the directory name
+    if (file.getName().equals(DartCore.PACKAGES_DIRECTORY_NAME)) {
+      file = file.getParentFile();
     }
 
-    // otherwise discard all cached libraries in the specified directory tree
-    else {
-      for (PackageContext packageContext : savedContext.getPackageContexts()) {
-        discardLibrariesIn(packageContext, rootFile);
-
-        // Discard any package contexts in the specified directory tree
-        if (equalsOrContains(rootFile, packageContext.getApplicationDirectory())) {
-          savedContext.discardPackageContext(packageContext);
-        }
-      }
-      discardLibrariesIn(savedContext, rootFile);
+    // Discard libraries and package contexts
+    if (server.getSavedContext().discardLibraries(file).size() == 0) {
+      return;
     }
 
-    // Remove any referenced libraries
-    int index = 0;
-    while (index < discardedLibraries.size()) {
-      Library library = discardedLibraries.get(index++);
-      for (PackageContext packageContext : savedContext.getPackageContexts()) {
-        discardReferencingLibraries(packageContext, library);
-      }
-      discardReferencingLibraries(savedContext, library);
-    }
-
-    // Remove all pending analysis tasks as they may have been related to the discarded library
+    // Remove all pending analysis tasks as they may have been related to the discarded libraries
     server.removeAllBackgroundAnalysisTasks();
+
     // Reanalyze any libraries not already cached
     server.queueAnalyzeContext();
   }
-
-  /**
-   * Discard all cached libraries in the specified directory tree
-   */
-  private void discardLibrariesIn(Context context, File directory) {
-    Collection<Library> cachedLibraries = new ArrayList<Library>(context.getCachedLibraries());
-    for (Library library : cachedLibraries) {
-      if (equalsOrContains(directory, library.getFile())) {
-        discardLibrary(context, library);
-      }
-    }
-  }
-
-  /**
-   * If there is a cached library, then discard the library and notify others that the library is no
-   * longer being analyzed
-   */
-  private void discardLibrary(Context context, File libraryFile) {
-    Library library = context.getCachedLibrary(libraryFile);
-    if (library != null) {
-      discardLibrary(context, library);
-    }
-  }
-
-  /**
-   * Discard the library and notify others that the library is no longer being analyzed
-   */
-  private void discardLibrary(Context context, Library library) {
-    AnalysisEvent event = new AnalysisEvent(
-        library.getFile(),
-        library.getSourceFiles(),
-        AnalysisError.NONE);
-
-    context.discardLibrary(library);
-    discardedLibraries.add(library);
-
-    for (AnalysisListener listener : savedContext.getAnalysisListeners()) {
-      try {
-        listener.discarded(event);
-      } catch (Throwable e) {
-        DartCore.logError("Exception during discard notification", e);
-      }
-    }
-  }
-
-  /**
-   * Discard any libraries referencing the specified library
-   */
-  private void discardReferencingLibraries(Context context, Library library) {
-    for (Library referencingLibrary : context.getLibrariesImporting(library.getFile())) {
-      discardLibrary(context, referencingLibrary);
-    }
-  }
 }