Authorize test:
import jwt from 'jsonwebtoken'
import config from '../../../config'
import middleware from '../../../middleware'
import { User } from '../../../database/models'

const { authorize } = middleware

test('Should call sendFailureResponse if user is not authorized', async () => {
    const req = {
      currentRecipe: {
          userId:1
      },
      authUser: {
          id:2
      },
    }

    const res = {
      sendFailureResponse: jest.fn()
    }

    const next = jest.fn()

    await authorize(req, res, next)

    expect(res.sendFailureResponse).toHaveBeenCalledWith({
      message: "Unauthorized."
    }, 401)
    expect(next).toHaveBeenCalledTimes(0)
  })

Has recipe test:
import middleware from '../../../middleware'
import { runInNewContext } from 'vm';

const { hasRecipe } = middleware

test ('The hasRecipe calls the sendFailureResponse function if the validation fails', async () => {
    const req = {
        params: {
            recipeId: '',
            id: ''
        }
    }

    //console.log (req)

    const res = {
        sendFailureResponse: jest.fn()
    }

    const next = jest.fn()

    await hasRecipe(req, res, next)
    expect(res.sendFailureResponse).toHaveBeenCalledWith({
        message:
            'Recipe not found.'

}, 404)

    expect(next).toHaveBeenCalledTimes(0)
})

Signin test:
import middleware from '../../../middleware'
import { runInNewContext } from 'vm';

const { signinUserValidator } = middleware

test ('The signinUserValidator calls the next function if the validation is successful', async () => {
    const req = {
        body: {
            name: 'bahdcoder',
            email: 'bahdcoder@gmail.com',
            password: 'password'
        }
    }

    const res = {
        sendFailurResponse() {}
    }

    const next = jest.fn()

    await signinUserValidator(req, res, next)
    expect(next).toHaveBeenCalled()
})