Added Jest and tests for EventBus

package.json

@@ -7,16 +7,22 @@
     "dev": "node esbuild.config.mjs",
     "build": "tsc -noEmit -skipLibCheck && node esbuild.config.mjs production",
     "version": "node version-bump.mjs && git add manifest.json versions.json package.json",
-    "lint": "eslint . --ext .ts --fix --ignore-path .gitignore"
+    "lint": "eslint . --ext .ts --fix --ignore-path .gitignore",
+    "test": "jest"
   },
   "keywords": [],
   "author": "",
   "license": "MIT",
   "devDependencies": {
+    "@babel/preset-env": "^7.16.11",
+    "@babel/preset-typescript": "^7.16.7",
+    "@testing-library/jest-dom": "^5.16.4",
     "@tsconfig/svelte": "^3.0.0",
+    "@types/jest": "^27.4.1",
     "@types/node": "^16.11.27",
     "@typescript-eslint/eslint-plugin": "^5.20.0",
     "@typescript-eslint/parser": "^5.20.0",
+    "babel-jest": "^27.5.1",
     "builtin-modules": "^3.2.0",
     "esbuild": "0.13.12",
     "esbuild-plugin-copy": "^1.3.0",
@@ -27,10 +33,12 @@
     "eslint-plugin-node": "11.1.0",
     "eslint-plugin-promise": "5.0.0",
     "eslint-plugin-svelte3": "^3.4.1",
+    "jest": "^27.5.1",
     "obsidian": "latest",
     "prettier": "^2.6.2",
     "prettier-eslint": "^13.0.0",
     "svelte": "^3.47.0",
+    "svelte-jester": "^2.3.2",
     "svelte-preprocess": "^4.10.6",
     "tslib": "2.3.1",
     "typescript": "^4.6.3"
@@ -38,4 +46,4 @@
   "dependencies": {
     "minisearch": "^5.0.0-beta1"
   }
-}
+}