Description
Current Behavior:
npm install in the eslint/eslint repository fails when it tries to resolve a transitive peer dependency on eslint@>=5.0.0 and finds eslint@undefined.
We want to dogfood eslint in development, so we specify it in our devDependencies as "eslint": "file:.". We also depend on a third-party plugin, eslint-plugin-eslint-plugin, which lists eslint@>=5.0.0 in its peerDependencies.
Running npm install reports ERESOLVE unable to resolve dependency tree having found eslint@undefined, which fails the eslint@>=5.0.0 requirement. (Full output and eresolve-report.txt included in the repro steps.)
eslint@7.13.0`s package.json snippet
```json
{
"name": "eslint",
"version": "7.13.0",
"devDependencies": {
"eslint": "file:.",
"eslint-plugin-eslint-plugin": "^2.2.1"
}
}
```
eslint-plugin-eslint-plugin@2.3.0`s package.json snippet
```json
{
"name": "eslint-plugin-eslint-plugin",
"version": "2.3.0",
"peerDependencies": {
"eslint": ">=5.0.0"
}
}
```
Expected Behavior:
Ideally, instead of finding eslint@undefined, eslint-plugin-eslint-plugin's eslint@>=5.0.0 peer dependency is satisifed by eslint@7.13.0, which is already "installed" from file:.. Install continues on as normal. (It won't succeed yet because I'm still working on upgrading another dependency to a newer version that lists eslint@^7.0.0 as a compatible peer dependency, but eslint-plugin-eslint-plugin at least should be happy.)
If that's not an option, our current solution so that we can test Node 15 in CI is to install with the --legacy-peer-deps flag. I also found that replacing file: dependencies with workspaces installs successfuly. At some point in the future when we can require at least npm v7, we could switch from --legacy-peer-deps to workspaces.
Steps To Reproduce:
$ node --version
v15.2.1
$ npm --version
7.0.10
$ git clone https://github.com/eslint/eslint.git
$ cd eslint
# Latest version as of writing in case a future commit no longer repros
$ git checkout v7.13.0
$ npm install
npm ERR! code ERESOLVE
npm ERR! ERESOLVE unable to resolve dependency tree
npm ERR!
npm ERR! While resolving: eslint@7.13.0
npm ERR! Found: eslint@undefined
npm ERR! node_modules/eslint
npm ERR! dev eslint@"file:." from the root project
npm ERR!
npm ERR! Could not resolve dependency:
npm ERR! peer eslint@">=5.0.0" from eslint-plugin-eslint-plugin@2.3.0
npm ERR! node_modules/eslint-plugin-eslint-plugin
npm ERR! dev eslint-plugin-eslint-plugin@"^2.2.1" 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.
npm ERR!
npm ERR! See ~/.npm/eresolve-report.txt for a full report.
npm ERR! A complete log of this run can be found in:
npm ERR! ~/.npm/_logs/2020-11-19T05_00_04_565Z-debug.log~/.npm/eresolve-report.txt
# npm resolution error report
2020-11-19T05:00:04.563Z
While resolving: eslint@7.13.0
Found: eslint@undefined
node_modules/eslint
dev eslint@"file:." from the root project
Could not resolve dependency:
peer eslint@">=5.0.0" from eslint-plugin-eslint-plugin@2.3.0
node_modules/eslint-plugin-eslint-plugin
dev eslint-plugin-eslint-plugin@"^2.2.1" from the root project
Fix the upstream dependency conflict, or retry
this command with --force, or --legacy-peer-deps
to accept an incorrect (and potentially broken) dependency resolution.
Raw JSON explanation object:
{
"code": "ERESOLVE",
"current": {
"name": "eslint",
"errors": [
{}
],
"package": {},
"whileInstalling": {
"name": "eslint",
"version": "7.13.0",
"path": "~/code/eslint/eslint"
},
"location": "node_modules/eslint",
"dependents": [
{
"type": "dev",
"name": "eslint",
"spec": "file:.",
"from": {
"location": "~/code/eslint/eslint"
}
}
]
},
"edge": {
"type": "peer",
"name": "eslint",
"spec": ">=5.0.0",
"error": "INVALID",
"from": {
"name": "eslint-plugin-eslint-plugin",
"version": "2.3.0",
"whileInstalling": {
"name": "eslint",
"version": "7.13.0",
"path": "~/code/eslint/eslint"
},
"location": "node_modules/eslint-plugin-eslint-plugin",
"dependents": [
{
"type": "dev",
"name": "eslint-plugin-eslint-plugin",
"spec": "^2.2.1",
"from": {
"location": "~/code/eslint/eslint"
}
}
]
}
},
"peerConflict": null,
"strictPeerDeps": false,
"force": false
}
Environment:
- OS: macOS 10.15.7
- Node: 15.2.1
- npm: 7.0.10