[BUG][Regression] ERESOLVE if peerDependencies of dependencies support later major version

[kevinoid]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

With npm@^7.20.3 or npm@8.0.0, when one of the peer dependencies of a dependency includes a later major version than the dependency version (in addition to the same major version), npm install --strict-peer-deps=true fails with ERESOLVE, as described in issue #2055.``

Expected Behavior

npm install should complete successfully with the latest version declared by the dependency (which also satisfies the peer dependency of the other dependency).

Steps To Reproduce

Using the same steps as #2055:

With package.json:

{
  "name": "project-a",
  "dependencies": {
    "webpack": "^4.41",
    "webpack-dev-server": "^3.9"
  }
}

Running npm install --strict-peer-deps=true produces:

npm ERR! code ERESOLVE
npm ERR! ERESOLVE could not resolve
npm ERR! 
npm ERR! While resolving: webpack-dev-server@3.11.2
npm ERR! Found: webpack@4.46.0
npm ERR! node_modules/webpack
npm ERR!   webpack@"^4.41" from the root project
npm ERR!   peer webpack@"^4.0.0 || ^5.0.0" from webpack-dev-server@3.11.2
npm ERR!   node_modules/webpack-dev-server
npm ERR!     webpack-dev-server@"^3.9" from the root project
npm ERR!   1 more (terser-webpack-plugin)
npm ERR! 
npm ERR! Could not resolve dependency:
npm ERR! webpack-dev-middleware@"^3.7.2" from webpack-dev-server@3.11.2
npm ERR! node_modules/webpack-dev-server
npm ERR!   webpack-dev-server@"^3.9" from the root project
npm ERR! 
npm ERR! Conflicting peer dependency: webpack@5.58.1
npm ERR! node_modules/webpack
npm ERR!   peer webpack@"^4.0.0 || ^5.0.0" from webpack-dev-middleware@3.7.3
npm ERR!   node_modules/webpack-dev-middleware
npm ERR!     webpack-dev-middleware@"^3.7.2" from webpack-dev-server@3.11.2
npm ERR!     node_modules/webpack-dev-server
npm ERR!       webpack-dev-server@"^3.9" from the root project
npm ERR! 
npm ERR! Fix the upstream dependency conflict, or retry
npm ERR! this command with --no-strict-peer-deps, --force, or --legacy-peer-deps
npm ERR! to accept an incorrect (and potentially broken) dependency resolution.
npm ERR! 
npm ERR! See /home/user/.cache/npm/eresolve-report.txt for a full report.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/user/.cache/npm/_logs/2021-10-09T21_37_39_782Z-debug.log

I would expect it to install webpack@4.46.0, since it is the latest version which satisfies the webpack@^4.41 dependency and it also satisfies the webpack@"^4.0.0 || ^5.0.0" peer dependency from webpack-dev-middleware@3.7.3.

Environment

• OS: Debian GNU/Linux testing
• Node: v12.22.5
• npm: npm@^7.20.3 or npm@8.0.0

I believe I've bisected the regression to 97cb5ec which upgraded to @npmcli/arborist@2.8.0 for #3377.

[kevinoid]

Another example:

package.json:

{
  "name": "project-a",
  "dependencies": {
    "eslint": "^7.0.0",
    "eslint-plugin-node": "^11.0.0"
  }
}

npm install --strict-peer-deps=true

npm ERR! code ERESOLVE
npm ERR! ERESOLVE could not resolve
npm ERR! 
npm ERR! While resolving: eslint-plugin-node@11.1.0
npm ERR! Found: eslint@7.32.0
npm ERR! node_modules/eslint
npm ERR!   eslint@"^7.0.0" from the root project
npm ERR!   peer eslint@">=5.16.0" from eslint-plugin-node@11.1.0
npm ERR!   node_modules/eslint-plugin-node
npm ERR!     eslint-plugin-node@"^11.0.0" from the root project
npm ERR! 
npm ERR! Could not resolve dependency:
npm ERR! eslint-plugin-es@"^3.0.0" from eslint-plugin-node@11.1.0
npm ERR! node_modules/eslint-plugin-node
npm ERR!   eslint-plugin-node@"^11.0.0" from the root project
npm ERR! 
npm ERR! Conflicting peer dependency: eslint@8.0.0
npm ERR! node_modules/eslint
npm ERR!   peer eslint@">=4.19.1" from eslint-plugin-es@3.0.1
npm ERR!   node_modules/eslint-plugin-es
npm ERR!     eslint-plugin-es@"^3.0.0" from eslint-plugin-node@11.1.0
npm ERR!     node_modules/eslint-plugin-node
npm ERR!       eslint-plugin-node@"^11.0.0" from the root project
npm ERR! 
npm ERR! Fix the upstream dependency conflict, or retry
npm ERR! this command with --no-strict-peer-deps, --force, or --legacy-peer-deps
npm ERR! to accept an incorrect (and potentially broken) dependency resolution.
npm ERR! 
npm ERR! See /home/user/.cache/npm/eresolve-report.txt for a full report.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/user/.cache/npm/_logs/2021-10-09T21_57_04_502Z-debug.log

[lukekarrys]

Thanks for the thorough report @kevinoid! This is the same issue as #3881, but manifesting in that ERESOLVE error when --strict-peer-deps is turned on. The good news is that the fix for that works for this as well. I pulled in npm/arborist#337 and was able to run both your examples successfully now. This fix should go out tomorrow!

{
  "dependencies": {
    "eslint": "^7.0.0",
    "eslint-plugin-node": "^11.0.0"
  }
}

❯ npm i --strict-peer-deps=true
❯ npm ls eslint
3868@1.0.0 /Users/lukekarrys/Desktop/npm-sandbox/3868
├─┬ eslint-plugin-node@11.1.0
│ ├─┬ eslint-plugin-es@3.0.1
│ │ └── eslint@7.32.0 deduped
│ └── eslint@7.32.0 deduped
└── eslint@7.32.0

{
  "dependencies": {
    "webpack": "^4.41",
    "webpack-dev-server": "^3.9"
  }
}

❯ npm i --strict-peer-deps=true
❯ npm ls webpack
3868@1.0.0 /Users/lukekarrys/Desktop/npm-sandbox/3868
├─┬ webpack-dev-server@3.11.2
│ ├─┬ webpack-dev-middleware@3.7.3
│ │ └── webpack@4.46.0 deduped
│ └── webpack@4.46.0 deduped
└─┬ webpack@4.46.0
  └─┬ terser-webpack-plugin@1.4.5
    └── webpack@4.46.0 deduped

[kevinoid]

Interesting! Thanks for investigating an implementing a fix @lukekarrys! I'll look forward to it in a future release.