There is a mismatch between your NodeJs version v12.14.1 and your TypeScript target ESNext

Question

I am using v12.14.1 version, in my project when try to type npm run test, I am getting this warning There is a mismatch between your NodeJs version v12.14.1 and your TypeScript target ESNext. This might lead to some unexpected errors when running tests with ts-jest

and all my test is failed, please can you say what node version should I use, or how can I fix this warning, to pass my tests

Answer 1

The answer is in this cheatsheet.

You are running node version 12, so you must set "target": "es2019" and "lib": ["ES2019"] in your tsconfig.json.

Example of what your tsconfig can look like:

{
  "compilerOptions": {
    "module": "commonjs",
    "moduleResolution": "node",
    "esModuleInterop": true,
    "noImplicitAny": false,
    "noImplicitReturns": true,
    "noUnusedLocals": true,
    "outDir": "./dist",
    "sourceMap": true,
    "strict": true,
    "target": "es2019",
    "lib": [
      "es2019",
      "es2020.bigint",
      "es2020.string",
      "es2020.symbol.wellknown"
    ],
    "typeRoots": ["node_modules/@types"],
    "resolveJsonModule": true
  },
  "compileOnSave": true,
  "include": ["./src/**/*"],
  "exclude": ["node_modules"]
}