Refactor Source.

sdk/lib/_internal/pub/test/lock_file_test.dart

Index: sdk/lib/_internal/pub/test/lock_file_test.dart
diff --git a/sdk/lib/_internal/pub/test/lock_file_test.dart b/sdk/lib/_internal/pub/test/lock_file_test.dart
index 29c9fcc569acf951d45eaadde30d53d577fc2019..f5cff29fe011ef9819d4f6b381f375cc2c4c1692 100644
--- a/sdk/lib/_internal/pub/test/lock_file_test.dart
+++ b/sdk/lib/_internal/pub/test/lock_file_test.dart
@@ -4,11 +4,14 @@
 
 library lock_file_test;
 
+import 'dart:async';
+
 import 'package:unittest/unittest.dart';
 import 'package:yaml/yaml.dart';
 
 import '../lib/src/lock_file.dart';
 import '../lib/src/package.dart';
+import '../lib/src/pubspec.dart';
 import '../lib/src/source.dart';
 import '../lib/src/source_registry.dart';
 import '../lib/src/version.dart';
@@ -16,7 +19,15 @@ import 'test_pub.dart';
 
 class MockSource extends Source {
   final String name = 'mock';
-  final bool shouldCache = false;
+
+  Future<Pubspec> onDescribe(PackageId id) => throw new UnsupportedError(
+      "Cannot describe mock packages.");
+
+  Future<bool> get(PackageId id, String path) => throw new UnsupportedError(
+      "Cannot get a mock package.");
+
+  Future<String> getDirectory(PackageId id) => throw new UnsupportedError(
+      "Cannot get the directory for mock packages.");
 
   dynamic parseDescription(String filePath, String description,
                            {bool fromLockFile: false}) {
@@ -24,6 +35,9 @@ class MockSource extends Source {
     return description;
   }
 
+  bool descriptionsEqual(description1, description2) =>
+      description1 == description2;
+
   String packageName(String description) {
     // Strip off ' desc'.
     return description.substring(0, description.length - 5);