recompute package map when input file changes

pkg/analysis_server/test/context_manager_test.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 test.context.directory.manager;
 
 import 'dart:collection';
 
 import 'package:analysis_server/src/context_manager.dart';
 import 'package:analysis_server/src/source/optimizing_pub_package_map_provider.dart';
@@ skipping 840 matching lines @@
     // Change the package map dependency so that the packageMapProvider is
     // re-run, and arrange for it to return null from computePackageMap().
     packageMapProvider.packageMap = null;
     resourceProvider.modifyFile(dependencyPath, 'new contents');
     return pumpEventQueue().then((_) {
       // The package map should have been changed to null.
       _checkPackageMap(projPath, isNull);
     });
   }
 
+  test_watch_modifyPackageMapDependency_outsideProject() {
+    // create a dependency file
+    String dependencyPath = '/my/other/dep';
+    resourceProvider.newFile(dependencyPath, 'contents');
+    packageMapProvider.dependencies.add(dependencyPath);
+    // create a Dart file
+    String dartFilePath = posix.join(projPath, 'main.dart');
+    resourceProvider.newFile(dartFilePath, 'contents');
+    // the created context has the expected empty package map
+    manager.setRoots(<String>[projPath], <String>[], <String, String>{});
+    _checkPackageMap(projPath, isEmpty);
+    // configure package map
+    String packagePath = '/package/foo';
+    resourceProvider.newFolder(packagePath);
+    packageMapProvider.packageMap = {'foo': projPath};
+    // Changing a .dart file in the project shouldn't cause a new
+    // package map to be picked up.
+    resourceProvider.modifyFile(dartFilePath, 'new contents');
+    return pumpEventQueue().then((_) {
+      _checkPackageMap(projPath, isEmpty);
+      // However, changing the package map dependency should.
+      resourceProvider.modifyFile(dependencyPath, 'new contents');
+      return pumpEventQueue().then((_) {
+        _checkPackageMap(projPath, equals(packageMapProvider.packageMap));
+      });
+    });
+  }
+
   test_watch_modifyPackageMapDependency_redundantly() async {
     // Create two dependency files
     String dependencyPath1 = posix.join(projPath, 'dep1');
     String dependencyPath2 = posix.join(projPath, 'dep2');
     resourceProvider.newFile(dependencyPath1, 'contents');
     resourceProvider.newFile(dependencyPath2, 'contents');
     packageMapProvider.dependencies.add(dependencyPath1);
     packageMapProvider.dependencies.add(dependencyPath2);
     // Create a dart file
     String dartFilePath = posix.join(projPath, 'main.dart');
@@ skipping 160 matching lines @@
     // causing the analyzer to thrash, just ignore links to non-existent files.
     return file.exists;
   }
 
   @override
   void updateContextPackageUriResolver(
       Folder contextFolder, UriResolver packageUriResolver) {
     currentContextPackageUriResolvers[contextFolder.path] = packageUriResolver;
   }
 }