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analyzer/lib/src/plugin/command_line_plugin.dart

-// Copyright (c) 2015, 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 analyzer.src.plugin.command_line_plugin;
-
-import 'package:analyzer/plugin/command_line.dart';
-import 'package:plugin/plugin.dart';
-
-/**
- * A plugin that defines the extension points and extensions that are defined by
- * command-line applications using the analysis engine.
- */
-class CommandLinePlugin implements Plugin {
-  /**
-   * The simple identifier of the extension point that allows plugins to
-   * register new parser contributors.
-   */
-  static const String PARSER_CONTRIBUTOR_EXTENSION_POINT = 'parserContributor';
-
-  /**
-   * The simple identifier of the extension point that allows plugins to
-   * register new result processors.
-   */
-  static const String RESULT_PROCESSOR_EXTENSION_POINT = 'resultProcessor';
-
-  /**
-   * The unique identifier of this plugin.
-   */
-  static const String UNIQUE_IDENTIFIER = 'command_line.core';
-
-  /**
-   * The extension point that allows plugins to register new parser
-   * contributors.
-   */
-  ExtensionPoint parserContributorExtensionPoint;
-
-  /**
-   * The extension point that allows plugins to register new result processors.
-   */
-  ExtensionPoint resultProcessorExtensionPoint;
-
-  /**
-   * Initialize a newly created plugin.
-   */
-  CommandLinePlugin();
-
-  /**
-   * Return a list containing all of the parser contributors that were
-   * contributed.
-   */
-  List<ArgParserContributor> get parserContributors =>
-      parserContributorExtensionPoint.extensions;
-
-  /**
-   * Return a list containing all of the result processors that were
-   * contributed.
-   */
-  List<ArgResultsProcessor> get resultProcessors =>
-      resultProcessorExtensionPoint.extensions;
-
-  @override
-  String get uniqueIdentifier => UNIQUE_IDENTIFIER;
-
-  @override
-  void registerExtensionPoints(RegisterExtensionPoint registerExtensionPoint) {
-    parserContributorExtensionPoint = registerExtensionPoint(
-        PARSER_CONTRIBUTOR_EXTENSION_POINT,
-        _validateParserContributorExtension);
-    resultProcessorExtensionPoint = registerExtensionPoint(
-        RESULT_PROCESSOR_EXTENSION_POINT, _validateResultProcessorExtension);
-  }
-
-  @override
-  void registerExtensions(RegisterExtension registerExtension) {
-    // There are no default extensions.
-  }
-
-  /**
-   * Validate the given extension by throwing an [ExtensionError] if it is not a
-   * valid parser contributor.
-   */
-  void _validateParserContributorExtension(Object extension) {
-    if (extension is! ArgParserContributor) {
-      String id = parserContributorExtensionPoint.uniqueIdentifier;
-      throw new ExtensionError(
-          'Extensions to $id must be an ArgParserContributor');
-    }
-  }
-
-  /**
-   * Validate the given extension by throwing an [ExtensionError] if it is not a
-   * valid result processor.
-   */
-  void _validateResultProcessorExtension(Object extension) {
-    if (extension is! ArgResultsProcessor) {
-      String id = resultProcessorExtensionPoint.uniqueIdentifier;
-      throw new ExtensionError(
-          'Extensions to $id must be an ArgResultsProcessor');
-    }
-  }
-}