Simple test using sinon in a mock model to listen on whether a function was called or not

thought-service.test.js

describe('updateLike test', () => {
  it('should updates the heart count', () => {
    const MockModel = {
      findOneAndUpdate: sinon.spy()
    }
    const thoughtService = ThoughtService(MockModel)
    thoughtService.updateLikes()
    const actual = MockModel.findOneAndUpdate.calledOnce
    const expected = true
    expect(actual).toEqual(expected)
  })
})