anchor.diff:                  'type, and cannot be stubbed.');
         }
       } else if (returnType is analyzer.FunctionType) {
  -      errorMessages
  -          .addAll(_checkFunction(returnType, name, className, entryLib));
  +      errorMessages.addAll(_checkFunction(returnType, name, className));
       } else if (returnType is analyzer.TypeParameterType) {
         if (function.returnType is analyzer.TypeParameterType &&
  -          entryLib.typeSystem.isPotentiallyNonNullable(function.returnType)) {
  +          _entryLib.typeSystem.isPotentiallyNonNullable(function.returnType)) {
           errorMessages
               .add("The method '$className.$name' features a non-nullable "
                   'unknown return type, and cannot be stubbed.');
  
positive.code:     return classesToMock;
    }
  
    void _checkClassesToMockAreValid(
        List<analyzer.DartType> classesToMock, LibraryElement entryLib) {
      var classesInEntryLib = entryLib.topLevelElements.whereType<ClassElement>();
      var classNamesToMock = <String, ClassElement>{};
      for (var class_ in classesToMock) {
        var name = class_.element.name;
        if (classNamesToMock.containsKey(name)) {
          var firstSource = classNamesToMock[name].source.fullName;
  
negative.code:     var classesToMock =
          _mapAnnotationValuesToClasses(objectsToMock, entryLib.typeProvider);
  
      return _MockTargetGatherer._(entryLib, classesToMock);
    }
  
    /// Map the values passed to the GenerateMocks annotation to the classes which
  