anchor.diff:    var labelContext = label == null ? '' : '-$label';
     var launcher = SubprocessLauncher(
         'build-$pubPackageName$versionContext$labelContext', env);
  -  var args = [
  +  await launcher.runStreamed(Platform.resolvedExecutable, [
  +    'pub',
       'cache',
       'add',
       if (version != null) ...['-v', version],
       pubPackageName,
  -  ];
  -  await launcher.runStreamed('pub', args);
  +  ]);
     var cache =
         Directory(path.join(env['PUB_CACHE']!, 'hosted', 'pub.dartlang.org'));
     var pubPackageDirOrig =
  
positive.code:     }
    }
  
    await launcher.runStreamed('pub', ['get'],
        workingDirectory: _languageTestPackageDir.absolute.path);
    await launcher.runStreamed(
        Platform.resolvedExecutable,
  
negative.code:         environment: flutterRepo.env,
          workingDirectory: pubPackageDir.absolute.path);
    } else {
      await launcher.runStreamed(Platform.resolvedExecutable, ['pub', 'get'],
          workingDirectory: pubPackageDir.absolute.path);
      await launcher.runStreamed(
          Platform.resolvedExecutable,
  