anchor.diff:    }) : super(
             name: name,
             cwd: cwd,
  +          // env is not supported for Dart attach because we don't spawn a process.
  +          env: null,
             restart: restart,
             additionalProjectPaths: additionalProjectPaths,
             debugSdkLibraries: debugSdkLibraries,
  
positive.code: }
  
  /// An implementation of [LaunchRequestArguments] that includes all fields used
  /// by the base Dart debug adapter.
  ///
  /// This class represents the data passed from the client editor to the debug
  /// adapter in launchRequest, which is a request to start debugging an
  /// application.
  ///
  /// Specialised adapters (such as Flutter) will likely have their own versions
  /// of this class.
  class DartLaunchRequestArguments extends DartCommonLaunchAttachRequestArguments
      implements LaunchRequestArguments {
    /// If noDebug is true the launch request should launch the program without
  
negative.code:     required this.restart,
      required this.name,
      required this.cwd,
      required this.env,
      required this.additionalProjectPaths,
      required this.debugSdkLibraries,
      required this.debugExternalPackageLibraries,
  