Testing a component where map is being loaded using esri-loader

Question

In my React application there is a map which is being loaded using esri loader. Below is the code for loading map with the help of esri-loader using React.

App.js

import React, { useEffect } from "react";
import { loadModules } from "esri-loader";

import "./App.css";

export default function App() {


  let mapView;

  useEffect(()=>{
    //load the api modules
    loadModules(
  [
    'esri/Map',
    'esri/views/MapView', 
    'esri/widgets/ScaleBar',
    'esri/widgets/Home',
    "esri/layers/FeatureLayer",
  ], { css:true })
.then(([Map, MapView, ScaleBar, Home, FeatureLayer])=>{
  
  let featureLayer = new FeatureLayer({
    url:
               "https://services.arcgis.com/xdbDcZrQnv51VAwh/arcgis/rest/services/US_City_Population/FeatureServer"
  });
  
  
  let map = new Map({
    basemap: "topo-vector",
    ground: "world-elevation",
    layers: [featureLayer]
  });

  mapView = new MapView({
    map: map,
    container: "viewDiv"
  })
})

return(
  <div className='App'>
     <div className='mainDiv>
        <div id='viewDiv'>
        </div>
     </div>
  </div>
)

  

I want to create a unit test file which will test if the map has been loaded or not. I am very new to unit testing in React. There hasn't been much which was put to use here. Would really appreciate any suggestions?