[BUG] Local path peerDependencies behave like dependencies

[DanKaplanSES]

Is there an existing issue for this?

• I have searched the existing issues

This issue exists in the latest npm version

• I am using the latest npm

Current Behavior

App depends on Lib. Lib has a peerDependency on jsdom.

I believe App's jsdom stack traces should come from app-package because jsdom is a peerDependency of lib-package. That is not the case:

C:\MyPackages\jsdom-sandbox\lib-package\node_modules\jsdom\lib\api.js:321
        throw new TypeError("resources must be an instance of ResourceLoader");
              ^

TypeError: resources must be an instance of ResourceLoader
    at resourcesToResourceLoader (C:\MyPackages\jsdom-sandbox\lib-package\node_modules\jsdom\lib\api.js:321:15)
    at transformOptions (C:\MyPackages\jsdom-sandbox\lib-package\node_modules\jsdom\lib\api.js:263:46)
    at new JSDOM (C:\MyPackages\jsdom-sandbox\lib-package\node_modules\jsdom\lib\api.js:34:15)
    at JSDOM.fromFile (C:\MyPackages\jsdom-sandbox\lib-package\node_modules\jsdom\lib\api.js:152:12)

Explicitly adding jsdom as a dependency to app-package makes no difference.

Expected Behavior

C:\MyPackages\jsdom-sandbox\app-package\node_modules\jsdom\lib\api.js:321
        throw new TypeError("resources must be an instance of ResourceLoader");
              ^

TypeError: resources must be an instance of ResourceLoader
    at resourcesToResourceLoader (C:\MyPackages\jsdom-sandbox\app-package\node_modules\jsdom\lib\api.js:321:15)
    at transformOptions (C:\MyPackages\jsdom-sandbox\app-package\node_modules\jsdom\lib\api.js:263:46)
    at new JSDOM (C:\MyPackages\jsdom-sandbox\app-package\node_modules\jsdom\lib\api.js:34:15)
    at JSDOM.fromFile (C:\MyPackages\jsdom-sandbox\app-package\node_modules\jsdom\lib\api.js:152:12)

Steps To Reproduce

1. Git clone https://github.com/DanKaplanSES/jsdom-sandbox/tree/local-path-peer-dependencies-reproducible
2. cd local-path-peer-dependencies-reproducible
3. ./setup.sh
4. ./npma.sh run exec

This is related to #5108

Environment

• npm: 10.3.0
• Node.js: 20.10.0
• OS Name: Windows
• System Model Name: 10
• npm config:

; "builtin" config from C:\Users\myuser\AppData\Roaming\npm\node_modules\npm\npmrc

prefix = "C:\\Users\\myuser\\AppData\\Roaming\\npm"

; "user" config from C:\cygwin64\home\myuser\.npmrc

//registry.npmjs.org/:_authToken = (protected)
registry = "https://registry.npmjs.org/"
script-shell = "C:\\cygwin64\\bin\\bash.exe"

; node bin location = C:\Program Files\nodejs\node.exe
; node version = v20.10.0
; npm local prefix = C:\my-projects\jsdom-sandbox
; npm version = 10.3.0
; cwd = C:\my-projects\jsdom-sandbox
; HOME = C:\cygwin64\home\myuser
; Run `npm config ls -l` to show all defaults.

[DanKaplanSES]

This is an issue in yarn too. Fortunately, a comment provides a workaround that works in both package managers:

for those wondering; I ran into the same issue and used yalc to fix my problem.

[kchindam-infy]

This issue can be resolved by using --install-links during npm install. Eg: npm i --install -links. --install-links option helps in installing the local dependenciesas packages instead of creating a symlink in the node_modules of app-package. Ref: https://docs.npmjs.com/cli/v8/commands/npm-install

[DanKaplanSES]

That worked for me!

There's no documentation about using --install-links without an argument. Does that make it true or false?

---

That said, why should --install-links change the behavior of peerDependencies? That still seems like a bug to me: whether lib is a symlink or not, peerDependencies should act like peerDependencies, no?

[kchindam-infy]

No argument in this case is equivalent to true.
'npm i --install-links' is equivalent to 'npm i --install-links=true'