Add eslint. Add jest tests.

.babelrc

@@ -0,0 +1,3 @@
+{
+    "presets": ["@babel/preset-env"]
+}

.eslintignore

@@ -0,0 +1,5 @@
+dist/**
+node_modules/**
+webpack.config.js
+tests/**
+app/**

.eslintrc.json

@@ -0,0 +1,17 @@
+{
+  "extends": "eslint:recommended",
+  "env": {
+    "browser": true,
+    "node": true
+  },
+  "parserOptions": {
+    "sourceType": "module",
+    "ecmaVersion": 2020
+  },
+  "rules": {
+    "no-unused-vars": "off"
+  },
+  "globals": {
+    "globalThis": false
+  }  
+}

.gitignore

@@ -2,4 +2,6 @@
 /node_modules/
 package-lock.json
 .DS_Store
-/module/
+/module/
+.eslintcache
+/coverage/

package.json

@@ -17,12 +17,14 @@
     "url": "https://github.com/ssc-ai/satsimjs/"
   },
   "main": "src/index.js",
+  "type": "module",
   "scripts": {
     "build": "webpack --config webpack.config.js",
     "watch": "webpack --config webpack.config.js --watch",
     "start": "webpack serve --config webpack.config.js --open",
     "test": "jest --verbose --runInBand",
-    "coverage": "jest --verbose --runInBand --collectCoverage"
+    "coverage": "jest --verbose --runInBand --collectCoverage",
+    "lint": "eslint \"./**/*.js\" --cache --quiet"
   },
   "jest": {
     "testEnvironment": "node",
@@ -31,11 +33,14 @@
     ]
   },
   "devDependencies": {
-    "@babel/core": "^7.23.2",
+    "@babel/core": "^7.24.4",
+    "@babel/preset-env": "^7.24.4",
+    "babel-jest": "^29.7.0",
     "babel-loader": "^9.1.3",
     "copy-webpack-plugin": "^9.0.1",
     "css-loader": "^6.2.0",
-    "eslint": "^8.50.0",
+    "eslint": "^8.57.0",
+    "eslint-plugin-node": "^11.1.0",
     "html-webpack-plugin": "^5.3.2",
     "jest": "^29.7.0",
     "style-loader": "^3.2.1",
@@ -45,7 +50,7 @@
     "webpack-dev-server": "^4.3.1"
   },
   "dependencies": {
-    "cesium": "^1.113.0",
+    "cesium": "^1.115.0",
     "mathjs": "^11.11.1",
     "satellite.js": "^5.0.0"
   }

webpack.config.js

@@ -1,12 +1,16 @@
+import CopyWebpackPlugin from 'copy-webpack-plugin';
+import path from 'path';
+import webpack from 'webpack';
+import HtmlWebpackPlugin from 'html-webpack-plugin';
+import { fileURLToPath } from 'url';
+
 // The path to the CesiumJS source code
 const cesiumSource = 'node_modules/cesium/Source';
 const cesiumWorkers = '../Build/Cesium/Workers';
-const CopyWebpackPlugin = require('copy-webpack-plugin');
-const path = require('path');
-const webpack = require('webpack');
-const HtmlWebpackPlugin = require('html-webpack-plugin');
+const __filename = fileURLToPath(import.meta.url); // get the resolved path to the file
+const __dirname = path.dirname(__filename); // get the name of the directory
 
-module.exports = {
+export default {
     context: __dirname,
     entry: {
         app: './app/index.js'
@@ -22,7 +26,7 @@ module.exports = {
         // add satsim as an alias to the root directory
         alias: {
             "satsim": path.resolve(__dirname, ".")
-          }        
+        }
     },
     module: {
         rules: [{