realtime: Improve testing framework

We were using mocha which presented some challenges and less than good experience when it came to testing. We're moving to vitest and we're also using Typescript in our testing to easily catch some of the typing issues that might arise earlier.

We're also adding a coverage so later we can setup CI to take that into consideration.

Author: filipecabaco

.gitignore

@@ -3,3 +3,4 @@ dist
 docs/v2
 .env
 .nyc_output
+coverage/

package-lock.json

@@ -23,14 +23,16 @@
   "repository": "https://github.com/supabase/realtime-js",
   "author": "Supabase",
   "license": "MIT",
+  "type": "module",
   "scripts": {
     "clean": "rimraf dist docs/v2",
     "format": "prettier --write \"{src,test}/**/*.ts\"",
     "build": "run-s clean format build:*",
     "build:main": "tsc -p tsconfig.json",
     "build:module": "tsc -p tsconfig.module.json",
-    "mocha": "node -r esm node_modules/.bin/mocha ./test/**/*.js -r jsdom-global/register",
-    "test": "run-s clean build mocha",
+    "test": "vitest run",
+    "test:watch": "vitest",
+    "coverage": "vitest run --coverage",
     "docs": "typedoc src/index.ts --out docs/v2",
     "docs:json": "typedoc --json docs/v2/spec.json --excludeExternals src/index.ts"
   },
@@ -41,18 +43,19 @@
     "ws": "^8.14.2"
   },
   "devDependencies": {
+    "@vitest/coverage-v8": "^2.0.5",
     "eslint": "^7.0.0",
     "esm": "^3.2.25",
     "jsdom": "^16.7.0",
     "jsdom-global": "3.0.0",
-    "mocha": "^8.0.1",
     "mock-socket": "^9.0.3",
     "npm-run-all": "^4.1.5",
     "nyc": "^15.1.0",
     "prettier": "^2.1.2",
     "semantic-release-plugin-update-version-in-files": "^1.1.0",
     "sinon": "^9.0.2",
     "typedoc": "^0.22.16",
-    "typescript": "^4.0.3"
+    "typescript": "^4.0.3",
+    "vitest": "^2.0.5"
   }
 }

package.json

@@ -176,7 +176,6 @@ export default class RealtimeClient {
       })
       return
     }
-
     if (NATIVE_WEBSOCKET_AVAILABLE) {
       this.conn = new WebSocket(this._endPointURL())
       this.setupConnection()