anchor.diff:  String _indent(String input) =>
       LineSplitter.split(input).map((l) => '  $l'.trimRight()).join('\n');
   
  -void _printUsage(ArgParser parser) {
  +void _printUsage() {
     print('''Usage: pubviz [<args>] <command> [<package path>]
   
   ${styleBold.wrap('Commands:')}
  
positive.code:   } on FormatException catch (e) {
      print(red.wrap(e.message));
      print('');
      _printUsage(parser);
      exitCode = ExitCode.usage.code;
      return;
    }
  
    if (options.help) {
      _printUsage(parser);
      return;
    }
  
  
negative.code: import 'dart:convert';
  import 'dart:io';
  
  import 'package:io/io.dart';
  import 'package:io/ansi.dart';
  import 'package:path/path.dart' as p;
  