Add an analyzer option to properly check ".call" methods.

pkg/analyzer/lib/options.dart

 // Copyright (c) 2013, 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 options;
 
 import 'dart:io';
 
 import 'package:args/args.dart';
 
 const _BINARY_NAME = 'dartanalyzer';
 
 /**
  * Analyzer commandline configuration options.
  */
 class CommandLineOptions {
   /** The path to the dart SDK */
   final String dartSdkPath;
 
   /** A table mapping the names of defined variables to their values. */
   final Map<String, String> definedVariables;
 
   /** Whether to report hints */
   final bool disableHints;
 
   /** Whether to display version information */
   final bool displayVersion;
 
   /**
+   * Whether to strictly follow the specification when generating warnings on
+   * "call" methods (fixes dartbug.com/21938).
+   */
+  final bool enableStrictCallChecks;
+
+  /**
    * Whether to treat type mismatches found during constant evaluation as
    * errors.
    */
   final bool enableTypeChecks;
 
   /** Whether to ignore unrecognized flags */
   final bool ignoreUnrecognizedFlags;
 
   /** Whether to log additional analysis messages and exceptions */
   final bool log;
@@ skipping 33 matching lines @@
   /**
    * Initialize options from the given parsed [args].
    */
   CommandLineOptions._fromArgs(ArgResults args,
       Map<String, String> definedVariables,
       Map<String, String> customUrlMappings)
       : dartSdkPath = args['dart-sdk'],
         this.definedVariables = definedVariables,
         disableHints = args['no-hints'],
         displayVersion = args['version'],
+        enableStrictCallChecks = args['enable-strict-call-checks'],
         enableTypeChecks = args['enable_type_checks'],
         ignoreUnrecognizedFlags = args['ignore-unrecognized-flags'],
         log = args['log'],
         machineFormat = args['machine'] || args['format'] == 'machine',
         packageRootPath = args['package-root'],
         perf = args['perf'],
         shouldBatch = args['batch'],
         showPackageWarnings = args['show-package-warnings'] ||
             args['package-warnings'],
         showSdkWarnings = args['show-sdk-warnings'] || args['warnings'],
@@ skipping 106 matching lines @@
       ..addFlag('enable-async',
           help: 'Enable support for the proposed async feature',
           defaultsTo: false,
           negatable: false,
           hide: true)
       ..addFlag('enable-enum',
           help: 'Enable support for the proposed enum feature',
           defaultsTo: false,
           negatable: false,
           hide: true)
+      ..addFlag('enable-strict-call-checks',
+          help: 'Fix issue 21938',
+          defaultsTo: false,
+          negatable: false,
+          hide: true)
       ..addFlag('log',
           help: 'Log additional messages and exceptions',
           defaultsTo: false,
           negatable: false,
           hide: true)
       ..addFlag('warm-perf',
           help: 'Show both cold and warm performance statistics',
           defaultsTo: false,
           negatable: false,
           hide: true)
@@ skipping 192 matching lines @@
 
   _getNextFlagIndex(args, i) {
     for (; i < args.length; ++i) {
       if (args[i].startsWith('--')) {
         return i;
       }
     }
     return i;
   }
 }