anchor.diff:  import 'dart:io';
   
   import 'package:args/command_runner.dart';
  +import 'package:async/async.dart';
   import 'package:build_runner_core/build_runner_core.dart';
   import 'package:io/io.dart';
   import 'package:path/path.dart' as p;
  
positive.code:           precompiledPath,
          ]..addAll(extraTestArgs),
          mode: ProcessStartMode.inheritStdio);
      return testProcess.exitCode;
    }
  }
  
negative.code:   }
  }
  
  void _ensureProcessExit(Process process) {
    var signalsSub = _exitProcessSignals.listen((signal) async {
      stdout.writeln('waiting for subprocess to exit...');
    });
    process.exitCode.then((_) {
      signalsSub?.cancel();
      signalsSub = null;
    });
  }
  
  Stream<ProcessSignal> get _exitProcessSignals => Platform.isWindows
      ? ProcessSignal.sigint.watch()
      : StreamGroup.merge(
          [ProcessSignal.sigterm.watch(), ProcessSignal.sigint.watch()]);
  
  class _BuildTestDependencyError extends StateError {
    _BuildTestDependencyError() : super('''
  Missing dev dependency on package:build_test, which is required to run tests.
  