anchor.diff:  class AnalysisError implements Comparable<AnalysisError> {
     AnalysisError(
       this.writtenError, {
  -    @required Platform platform,
  -    @required Terminal terminal,
  -    @required FileSystem fileSystem,
  +    required Platform platform,
  +    required Terminal terminal,
  +    required FileSystem fileSystem,
     }) : _platform = platform,
          _terminal = terminal,
          _fileSystem = fileSystem;
  
positive.code: 
    Stream<FileAnalysisErrors> get onErrors => _errorsController.stream;
  
    Future<int> get onExit => _process.exitCode;
  
    void _sendCommand(String method, Map<String, dynamic> params) {
      final String message = json.encode(<String, dynamic>{
  
negative.code: // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  import 'dart:async';
  import 'dart:math' as math;
  
  import 'package:process/process.dart';
  
  import '../base/common.dart';
  