feat: add automocking in vitest (#666)

* feat: add automocking in vitest

* fix: integrate eslint and prettier correctly

When running the lint command, Eslint was displaying an error and not
working.

This commit fix this by:

- Updating dependencies by running `yarn upgrade`
- Setting up `eslint-plugin-prettier`

* fix: fix lint error due to dependencies in example

README.md

@@ -191,9 +191,9 @@ const buffer = storage.getBuffer('someToken')
 console.log(buffer) // [1, 100, 255]
 ```
 
-## Testing with Jest
+## Testing with Jest or Vitest
 
-A mocked MMKV instance is automatically used when testing with Jest, so you will be able to use `new MMKV()` as per normal in your tests. Refer to [example/test/MMKV.test.ts](example/test/MMKV.test.ts) for an example.
+A mocked MMKV instance is automatically used when testing with Jest or Vitest, so you will be able to use `new MMKV()` as per normal in your tests. Refer to [example/test/MMKV.test.ts](example/test/MMKV.test.ts) for an example using Jest.
 
 ## Documentation
 

package.json

@@ -70,8 +70,10 @@
     "@typescript-eslint/eslint-plugin": "^7.0.1",
     "@typescript-eslint/parser": "^7.0.1",
     "eslint": "^8.56.0",
+    "eslint-config-prettier": "^9.1.0",
     "eslint-plugin-ft-flow": "^3.0.4",
     "eslint-plugin-jest": "^27.8.0",
+    "eslint-plugin-prettier": "^5.1.3",
     "jest": "^29.7.0",
     "metro-react-native-babel-preset": "^0.77.0",
     "prettier": "^3.2.5",
@@ -138,7 +140,7 @@
     "root": true,
     "extends": [
       "@react-native-community",
-      "prettier"
+      "plugin:prettier/recommended"
     ],
     "plugins": [
       "jest"

src/MMKV.ts

@@ -1,6 +1,6 @@
 import { createMMKV } from './createMMKV';
 import { createMockMMKV } from './createMMKV.mock';
-import { isJest } from './PlatformChecker';
+import { isTest } from './PlatformChecker';
 
 interface Listener {
   remove: () => void;
@@ -131,7 +131,7 @@ export type NativeMMKV = Pick<
   | 'recrypt'
 >;
 
-const onValueChangedListeners = new Map<string, ((key: string) => void)[]>();
+const onValueChangedListeners = new Map<string, ((_key: string) => void)[]>();
 
 /**
  * A single MMKV instance.
@@ -147,7 +147,7 @@ export class MMKV implements MMKVInterface {
    */
   constructor(configuration: MMKVConfiguration = { id: 'mmkv.default' }) {
     this.id = configuration.id;
-    this.nativeInstance = isJest()
+    this.nativeInstance = isTest()
       ? createMockMMKV()
       : createMMKV(configuration);
     this.functionCache = {};

src/PlatformChecker.ts

@@ -1,7 +1,9 @@
-export function isJest(): boolean {
+export function isTest(): boolean {
   if (global.process == null) {
     // In a WebBrowser/Electron the `process` variable does not exist
     return false;
   }
-  return process.env.JEST_WORKER_ID != null;
+  return (
+    process.env.JEST_WORKER_ID != null || process.env.VITEST_WORKER_ID != null
+  );
 }

src/hooks.ts

@@ -51,7 +51,7 @@ export function useMMKV(configuration?: MMKVConfiguration): MMKV {
 function createMMKVHook<
   T extends (boolean | number | string | Uint8Array) | undefined,
   TSet extends T | undefined,
-  TSetAction extends TSet | ((current: T) => TSet)
+  TSetAction extends TSet | ((current: T) => TSet),
 >(getter: (instance: MMKV, key: string) => T) {
   return (
     key: string,
@@ -179,7 +179,12 @@ export const useMMKVBuffer = createMMKVHook((instance, key) =>
 export function useMMKVObject<T>(
   key: string,
   instance?: MMKV
-): [value: T | undefined, setValue: (value: T | undefined | ((prevValue: T | undefined) => T | undefined)) => void] {
+): [
+  value: T | undefined,
+  setValue: (
+    value: T | undefined | ((prevValue: T | undefined) => T | undefined)
+  ) => void,
+] {
   const [json, setJson] = useMMKVString(key, instance);
 
   const value = useMemo(() => {