anchor.diff:  // BSD-style license that can be found in the LICENSE file.
   
   import 'dart:async';
  -import 'dart:io';
   
   import 'package:logging/logging.dart';
   import 'package:pana/pana.dart';
  
positive.code:     }
  
      Future<Summary> analyze() async {
        Directory tempDir;
        final toolEnvRef = await getOrCreateToolEnvRef();
        try {
          tempDir = await Directory.systemTemp.createTemp('pana');
          final PackageAnalyzer analyzer =
              new PackageAnalyzer(toolEnvRef.toolEnv, urlChecker: _urlChecker);
          final isInternal = internalPackageNames.contains(job.packageName);
  
negative.code:             e,
              st);
        } finally {
          await toolEnvRef.release();
        }
        return null;
  