anchor.diff:  import 'dart:async';
   import 'dart:io';
   
  +import 'package:logging/logging.dart';
   import 'package:pana/pana.dart';
   
   import 'configuration.dart';
  +
  +final _logger = Logger('tool_env');
   
   /// Subsequent calls of the analyzer or dartdoc job can use the same [ToolEnvRef]
   /// instance [_maxCount] times.
  
positive.code: class ToolEnvRef {
    final Directory _pubCacheDir;
    final ToolEnvironment toolEnv;
    int _started = 0;
    int _active = 0;
    bool _isAboveSizeLimit = false;
  
negative.code:   while (result == null) {
      if (_current != null && _current._isAvailable) {
        result = _current;
        result._acquire();
        break;
      }
  
  