[BUG] Could not resolve peerDependencies of matching semver ranges

[Standard8]

Current Behavior:

Using the commands:

mkdir test
npm init
npm install [email protected]

Results in:

npm ERR! code ERESOLVE
npm ERR! ERESOLVE unable to resolve dependency tree
npm ERR! 
npm ERR! While resolving: [email protected]
npm ERR! Found: [email protected]
npm ERR! node_modules/prettier
npm ERR!   peer prettier@">=1.13.0" from [email protected]
npm ERR!   node_modules/eslint-plugin-prettier
npm ERR!     peer eslint-plugin-prettier@"^3.0.1" from [email protected]
npm ERR!     node_modules/eslint-plugin-mozilla
npm ERR!       eslint-plugin-mozilla@"*" from the root project
npm ERR! 
npm ERR! Could not resolve dependency:
npm ERR! peer prettier@"^1.17.0" from [email protected]
npm ERR! node_modules/eslint-plugin-mozilla
npm ERR!   eslint-plugin-mozilla@"*" from the root project
npm ERR! 
npm ERR! Fix the upstream dependency conflict, or retry
npm ERR! this command with --force, or --legacy-peer-deps
npm ERR! to accept an incorrect (and potentially broken) dependency resolution.

Expected Behavior:

I would expect that the modules are installed using prettier matching ^1.17.0. This would be matching the semver range of eslint-plugin-prettier and that of eslint-plugin-mozilla.

From the perspective of an author of eslint-plugin-mozilla, I think the only two choices we have here are:

1. Match the semver style of eslint-plugin-prettier, i.e. using "prettier": ">=1.17.0.", and "eslint": ">=5.0.0",.
2. Always ship the latest version of prettier in the peer dependencies.

The first is not sensible for eslint-plugin-mozilla since it depends on ESLint internals, and so we cannot make the same guarantee. I believe it is a reasonable guarantee for eslint-plugin-prettier to make.

The second is also not really viable, as it would break every time a new version of prettier was released until eslint-plugin-mozilla could also be updated.

This may be similar to #2164, but I'm not sure, and I think this points out an addition issue with the way peer dependencies are causing some conflicts between packages.

Steps To Reproduce:

eslint-plugin-mozilla has peer dependencies of:

  "peerDependencies": {
    "eslint-config-prettier": "^6.0.0",
    "eslint-plugin-fetch-options": "^0.0.5",
    "eslint-plugin-html": "^6.0.0",
    "eslint-plugin-no-unsanitized": "^3.1.4",
    "eslint-plugin-prettier": "^3.0.1",
    "eslint": "^7.8.0",
    "prettier": ">=1.13.0"
  },

eslint-plugin-prettier has peer dependencies of:

  "peerDependencies": {
    "eslint": ">=5.0.0",
    "prettier": ">=1.13.0"
  },

The above commands can be used to reproduce this.

Environment:

• OS: macOS 11.2.3
• Node: 15.12.0
• npm: 7.6.3

[cawa-93]

Similar issue with npm v7.8.0

$ npm i vue@^3.0.11

npm ERR! ERESOLVE unable to resolve dependency tree
npm ERR!
npm ERR! Found: [email protected]
npm ERR! node_modules/vue
npm ERR!   vue@"^3.0.11" from the root project
npm ERR!   peer vue@"^3.0.0" from [email protected]
npm ERR!   node_modules/vue-router
npm ERR!     vue-router@"^4.0.5" from the root project
npm ERR!
npm ERR! Could not resolve dependency:
npm ERR! peer vue@"3.0.10" from @vue/[email protected]
npm ERR! node_modules/@vue/compiler-sfc
npm ERR!   peer @vue/compiler-sfc@"^3.0.6" from @vitejs/[email protected]
npm ERR!   node_modules/@vitejs/plugin-vue
npm ERR!     dev @vitejs/plugin-vue@"^1.2.1" from the root project

At launch, the following packages had already been published:

• [email protected]
• @vue/[email protected]

Workaround for my case:

npm un @vitejs/plugin-vue
npm i vue@^3.0.11
npm i -D @vitejs/plugin-vue