How can the argument of Jest Mock Service be made assignable?

edit

To make the argument of Jest Mock Service assignable, you can do the following:

1. Create the mock service and assign it to a variable:

const mockService = jest.fn();

1. Use the mocked function in your test case by passing it as an argument:

test('Test case 1', () => {
  //...code...
  mockService(argument);
  //...assertions...
});

1. You can also modify the returned value of the mocked function by using the mockImplementation() method:

mockService.mockImplementation(() => 'mocked value');

This will change the returned value of the mocked function to 'mocked value'.

Overall, by assigning the Jest Mock Service to a variable, you can easily pass it as an argument to test cases and modify its behavior as needed.