How to mock Sequelize functions in Typescript

Question

I am writing unit test cases and I have sequelize.transaction in my function. How to I mock the sequelize.transaction function.

My function looks like

create = async (req: Request) => {

await sequelize.transaction(async (t) => {
  // Lock Test Balance Row
  const testBalance = await this.testBalanceDAL.findByTestTypeAndUserIdForUpdate(
    testTypeId,
    userId,
    t
  );.....`

Answer 1

const sequelize = require('sequelize');

jest.mock('sequelize', () => ({
  transaction: jest.fn(() => Promise.resolve()),
}));

describe('...', () => {
  it('should ...', () => {
    sequelize.transaction.mockImplementation(() => { ... });
    expect(sequelize.transaction).toBeCalled();
  });
});