[BUG] DevDependancy are installed in production when also marked as optional peerDependencies about cli HOT 8 OPEN

(but note that if you omit peers, your dep graph is invalid and can't work)

from cli.

@saziri-arrow The typescript is installed with npm install --omit=dev because its a peer dependency of ts-node not directly a devDependency. To prevent typescript from being installed you would need to omit peer dependencies with npm install --omit=peer.
You can check the documentation here : https://docs.npmjs.com/cli/v10/commands/npm-install#omit

from cli.

@saziri-arrow As pointed by Lijarb potential issues with omitting peer dependencies. If you are sure you can do selective omission instead of omitting all peer dependencies, consider manually managing them use a post-install script in package.json.

from cli.

Hello I can't use npm install --omit=peer since I need other peerDependencies obviously.
My question is :
Why ts-node is installed with --omit=dev since it's devDependancy and It's marked as optional peerDependancy in typeorm.
Optioannal peerDependancy should only match dependancy, not devDependancy don't you think ?
While the same configuration in root package.json will not install peerDependancy with -omit=dev :

"peerDependencies": { "ts-node": "^10.9.2" }, "peerDependenciesMeta": { "ts-node": { "optional": true } }, "devDependencies": { "ts-node": "^10.9.2" },

Also if you run npm uninstall ts-node, it will keep it since it's already install with typeorm peerDependancy (package-lock.json)

from cli.

The reason ts-node is still installed even with --omit=dev is because its listed as peer dependency of typeorm. When npm installs typeorm it sees ts-node as a peer dependency and installs it, regardless of whether its also listed as a devDependency in your root package.json. The npm uninstall ts-node does not remove because its still listed as a peer dependeny of typeorm in your package-lock.json. npm sees that its still required by another package in dependency tree and keeps it installed.

optional peer dependencies:
Marked as optional in the peerDependenciesMeta field, and are meant to be installed only if the package using them is installed.

from cli.

Hello ts-node will not be installed because it is marked as optional dependancy :

But it will be installed if I add ts-node it to my devDependancies. For you it is the correct behaviour ? Mixing devDependancies and PeerDependancies even if I write --omit=dev

from cli.