Add test

package.json

@@ -10,8 +10,14 @@
     "start": "node scripts/server.js",
     "build": "rimraf dist && webpack --config scripts/webpack.config.prod.js",
     "prepublishOnly": "npm run build",
-    "test": "mocha",
-    "lint": "eslint src"
+    "lint": "eslint src",
+    "wait": "rimraf dist && wait-on http://localhost:3000/dist/ffmpeg.dev.js",
+    "test": "npm-run-all -p -r start test:all",
+    "test:all": "npm-run-all wait test:browser:* test:node:all",
+    "test:node": "nyc mocha --exit --bail --require ./scripts/test-helper.js",
+    "test:node:all": "npm run test:node -- ./tests/*.test.js",
+    "test:browser": "mocha-headless-chrome -a incognito -a no-sandbox -a disable-setuid-sandbox -a disable-logging -t 300000",
+    "test:browser:ffmpeg": "npm run test:browser -- -f ./tests/ffmpeg.test.html"
   },
   "browser": {
     "./src/worker/node/index.js": "./src/worker/browser/index.js"
@@ -46,8 +52,13 @@
     "eslint": "^6.1.0",
     "eslint-config-airbnb-base": "^14.0.0",
     "eslint-plugin-import": "^2.18.2",
+    "expect.js": "^0.3.1",
     "express": "^4.17.1",
     "mocha": "^6.2.2",
+    "mocha-headless-chrome": "^2.0.3",
+    "npm-run-all": "^4.1.5",
+    "nyc": "^14.1.1",
+    "wait-on": "^3.3.0",
     "webpack": "^4.41.2",
     "webpack-cli": "^3.3.9",
     "webpack-dev-middleware": "^3.7.2"