Always ignore 'packages' folders.

pkg/analysis_server/lib/src/context_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 'dart:async';
 import 'dart:collection';
 
 import 'package:analysis_server/src/package_map_provider.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:path/path.dart' as pathos;
 import 'package:watcher/watcher.dart';
 
 
 /**
  * File name of pubspec files.
  */
 const String PUBSPEC_NAME = 'pubspec.yaml';
 
 
 /**
+ * The name of `packages` folders.
+ */
+const String PACKAGES_NAME = 'packages';
+
+
+/**
  * Class that maintains a mapping from included/excluded paths to a set of
  * folders that should correspond to analysis contexts.
  */
 abstract class ContextManager {
   /**
    * [_ContextInfo] object for each included directory in the most
    * recent successful call to [setRoots].
    */
   Map<Folder, _ContextInfo> _contexts = new HashMap<Folder, _ContextInfo>();
 
@@ skipping 150 matching lines @@
         continue;
       }
       // add files, recurse into folders
       if (child is File) {
         if (_shouldFileBeAnalyzed(child)) {
           Source source = child.createSource();
           changeSet.addedSource(source);
           info.sources[path] = source;
         }
       } else if (child is Folder) {
-        if (child.shortName == 'packages') {
-          // TODO(paulberry): perhaps we should only skip packages dirs if
-          // there is a pubspec.yaml?
+        if (child.shortName == PACKAGES_NAME) {
           continue;
         }
         _addPreviouslyExcludedSources(info, changeSet, child, oldExcludedPaths);
       }
     }
   }
 
   /**
    * Resursively adds all Dart and HTML files to the [changeSet].
    */
   void _addSourceFiles(ChangeSet changeSet, Folder folder, _ContextInfo info) {
     if (info.excludesResource(folder)) {
       return;
     }
     List<Resource> children = folder.getChildren();
     for (Resource child in children) {
       String path = child.path;
       // ignore excluded files or folders
       if (_isExcluded(path)) {
         continue;
       }
       // add files, recurse into folders
       if (child is File) {
         if (_shouldFileBeAnalyzed(child)) {
           Source source = child.createSource();
           changeSet.addedSource(source);
           info.sources[path] = source;
         }
       } else if (child is Folder) {
-        if (child.shortName == 'packages') {
-          // TODO(paulberry): perhaps we should only skip packages dirs if
-          // there is a pubspec.yaml?
+        if (child.shortName == PACKAGES_NAME) {
           continue;
         }
         _addSourceFiles(changeSet, child, info);
       }
     }
   }
 
   /**
    * Create a new empty context associated with [folder].
    */
@@ skipping 114 matching lines @@
       return;
     }
     // maybe excluded from the context, so other context will handle it
     if (info.excludes(path)) {
       return;
     }
     // handle the change
     switch (event.type) {
       case ChangeType.ADD:
         if (_isInPackagesDir(path, folder)) {
-          // TODO(paulberry): perhaps we should only skip packages dirs if
-          // there is a pubspec.yaml?
-          break;
+          return;
         }
         Resource resource = resourceProvider.getResource(path);
         // pubspec was added in a sub-folder, extract a new context
         if (_isPubspec(path) && info.isRoot && !info.isPubspec(path)) {
           _extractContext(info, resource);
           return;
         }
         // If the file went away and was replaced by a folder before we
         // had a chance to process the event, resource might be a Folder.  In
         // that case don't add it.
@@ skipping 63 matching lines @@
     });
   }
 
   /**
    * Determine if the path from [folder] to [path] contains a 'packages'
    * directory.
    */
   bool _isInPackagesDir(String path, Folder folder) {
     String relativePath = pathContext.relative(path, from: folder.path);
     List<String> pathParts = pathContext.split(relativePath);
-    for (int i = 0; i < pathParts.length - 1; i++) {
-      if (pathParts[i] == 'packages') {
-        return true;
-      }
-    }
-    return false;
+    return pathParts.contains(PACKAGES_NAME);
   }
 
   /**
    * Returns `true` if the given absolute [path] is a pubspec file.
    */
   bool _isPubspec(String path) {
     return pathContext.basename(path) == PUBSPEC_NAME;
   }
 
   /**
@@ skipping 99 matching lines @@
     return excludes(resource.path);
   }
 
   /**
    * Returns `true` if [path] is the pubspec file of this context.
    */
   bool isPubspec(String path) {
     return path == pubspecPath;
   }
 }