How can you mock dependencies when testing functions with multiple generic parameters

1. Use a generic mock function: Create a mock function that matches the signature of the original function, including the generic type parameters.

typescript
const myMockFunction = jest.fn().mockImplementation<
  <T, U>(arg1: T, arg2: U) => { /* mock implementation */ }
>());

2. Replace the original function with the mock: Use `jest.mock` or `jest.doMock` to replace the original function with your mock function.

typescript
jest.mock('./module', () => ({
  myFunction: myMockFunction,
}));

3. Use the mock function in your tests: In your test suite, call the mock function with the desired generic type arguments and assert the behavior.

typescript
test('mocks myFunction with generic parameters', () => {
  myMockFunction.mockReturnValueOnce('result');

  const result = myFunction<string, number>('hello', 42);
  expect(result).toBe('result');
  expect(myMockFunction).toHaveBeenCalledWith('hello', 42);
});

4. Restore mocks after each test: Use `afterEach` or `afterAll` to restore the mocks after each test or the entire suite, respectively.

typescript
afterEach(() => {
  jest.restoreAllMocks();
});

By following these steps, you can effectively mock dependencies when testing functions with multiple generic parameters in TypeScript:

- Use a generic mock function that matches the original function's signature.
- Replace the original function with the mock using `jest.mock` or `jest.doMock`.
- Use the mock function in your tests, specifying the generic type arguments.
- Restore the mocks after each test or the entire suite to ensure a clean state for subsequent tests.

This approach allows you to test functions with multiple generic parameters by mocking their dependencies and asserting the expected behavior.