anchor.diff:      }
     }
   
  -  bool _checkConflict(_TrielikePackageTreeHelper currentMapHelper,
  +  bool _checkConflict(_PackageTrieNode currentTrieNode,
         SimplePackage newPackage, void Function(Object error) onError) {
  -    if (currentMapHelper.package != null) {
  -      var existingPackage = currentMapHelper.package!;
  +    if (currentTrieNode.package != null) {
  +      var existingPackage = currentTrieNode.package!;
         // Trying to add package that is inside the existing package.
         // 1) If it's an exact match it's not allowed (i.e. the roots can't be
         //    the same).
  
positive.code:   SimplePackage? packageOf(Uri file);
  }
  
  class _TrielikePackageTreeHelper {
    SimplePackage? package;
    Map<String, _TrielikePackageTreeHelper> map = {};
  }
  
  /// Packages of a package configuration ordered by root path.
  
negative.code: /// root path.
  /// Entire other packages are allowed inside a package's root.
  class TrielikePackageTree implements PackageTree {
    final Map<String, _PackageTrieNode> _map = {};
  
    /// A list of all packages.
    final List<SimplePackage> _packages = [];
  