| // Copyright (c) 2012, 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 source_registry; |
| |
| import 'source.dart'; |
| |
| /// A class that keeps track of [Source]s used for installing packages. |
| class SourceRegistry { |
| final Map<String, Source> _map; |
| Source _default; |
| |
| /// Creates a new registry with no packages registered. |
| SourceRegistry() : _map = <String, Source>{}; |
| |
| /// Returns the default source, which is used when no source is specified. |
| Source get defaultSource => _default; |
| |
| /// Sets the default source. This takes a string, which must be the name of a |
| /// registered source. |
| void setDefault(String name) { |
| if (!_map.containsKey(name)) { |
| throw new StateError('Default source $name is not in the registry'); |
| } |
| |
| _default = _map[name]; |
| } |
| |
| /// Registers a new source. This source may not have the same name as a source |
| /// that's already been registered. |
| void register(Source source) { |
| if (_map.containsKey(source.name)) { |
| throw new StateError('Source registry already has a source named ' |
| '${source.name}'); |
| } |
| |
| _map[source.name] = source; |
| } |
| |
| /// Returns `true` if there is a source named [name]. |
| bool contains(String name) => _map.containsKey(name); |
| |
| /// Returns the source named [name]. Throws an error if no such source has |
| /// been registered. If [name] is null, returns the default source. |
| Source operator[](String name) { |
| if (name == null) { |
| if (defaultSource != null) return defaultSource; |
| throw new StateError('No default source has been registered'); |
| } |
| if (_map.containsKey(name)) return _map[name]; |
| throw new ArgumentError('No source named $name is registered'); |
| } |
| } |