repository_test.dart

import 'package:mockito/annotations.dart';
import 'package:mockito/mockito.dart';
import 'repository_test.mocks.dart'; // Don't forget to include this

@GenerateMocks([RemoteDateSource])
void main() {
  test("fetch() should return an instance of student on remoteDataSource's fetch success", () {
    //Arrange
    MockRemoteDateSource mockDS = MockRemoteDateSource();
    Repository repo = Repository(mockDS);
    when(mockDS.fetch()).thenReturn("Mock Result");
    //Act
    final result = repo.fetch();
    //Assert
    expect(result, isInstanceOf<Student>());
  });

  test("fetch() should throw an exception on remoteDataSource's fetch throws any exception", () {
    MockRemoteDateSource mockDS = MockRemoteDateSource();
    Repository repo = Repository(mockDS);
    when(mockDS.fetch()).thenThrow(SocketException("Mock exception"));
    expect(() => repo.fetch(), throwsException);
  });
}