Why are test libraries not scoped as dev dependencies?

[behrangsa]

Hi,

If you create a new app with the typescript template:

PS C:\...> npx create-react-app hello-world --template typescript

The generated package.json looks like this:

{
  "name": "hello-world",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "@testing-library/jest-dom": "^5.16.4",
    "@testing-library/react": "^13.3.0",
    "@testing-library/user-event": "^13.5.0",
    "@types/jest": "^27.5.2",
    "@types/node": "^16.11.45",
    "@types/react": "^18.0.15",
    "@types/react-dom": "^18.0.6",
    "react": "^18.2.0",
    "react-dom": "^18.2.0",
    "react-scripts": "5.0.1",
    "typescript": "^4.7.4",
    "web-vitals": "^2.1.4"
  },
  ...
}

Is there a reason why these libraries are not dev dependencies?

• @testing-library/jest-dom
• @testing-library/react
• @testing-library/user-event
• @types/jest

PS: 🤔 Do we have a :? or a ?: operator in English?

[jongwooo]

@behrangsa See Dan's point of view:

In the end we went with just putting everything into dependencies. If you disagree you can always rearrange package.json as you deem reasonable.