testing pattern

app.js

import makeGetUser from './github'
import request from './request'

const getUser = makeGetUser({request}) 

getUser('michaelwclark')
  .then(console.log)

github.js

//github.js

//but lets make it liek your example
const makeGetUser =  
   services => 
      user => 
          services.request(`https://api.github.com/users/${user}`)
     
 export default makeGetUser

github.spec.js

 

//github.spec.js
// Let's mock this bit$ch
import {assert, expect} from 'chai'
import makeGetUser from './github' //where did this come from? I get the exporting makeSerive but serviceMaker?
describe('makeGetUser', ()=> {

    it('should return a function',()=>{
        const mock_services = {}
        assert.isFunction(makeGetUser(mock_services))
    })//so this calls services request but enters nothing? why the need to make mock_services then instead of 
   //just doing makeGetUser()/makeGetUser('') 
    //the pattern i use is that services is always an object...so even in my tests i try to be explicit on how I call makeXXXYYY... i do a lot of m.akeGetUser, make makeGetMyBeer,makeGetMeMoreMoney...always passing in a service object to the make`r so i just wanted you to see services is just an object literal. { } 
    
    it('should call request', ()=>{
        let requestCalled = false
        const mock_request =  
              //under the covers this is what __mocks__ is doing with jest.mock... but instead of you passing 
              //it in, jest is tricky, black magic, and intercepting the request. They are doing it via convention, 
              //we are doing it explicitly so even if you don't know a lick of jest you can figure this code out.. 
              //i think
            (user) => {
                requestCalled=true
                expect(user).to.eql('michaelwclark')
                return 'hi wes'
            }         
            
        const mock_services = { request: mock_request} 
        const getUser = makeGetUser(mock_services)
        const result = getUser('michaelwclark')
        assert.isTrue(requestCalled)
        expect(result).to.eql('hi wes')
   })
})