[Bug?]: NodeLinker: pnpm, enableGlobalCache: false and enableMirror: false still populates the Global cache

[X-Guardian]

Self-service

• I'd be willing to implement a fix

Describe the bug

With nodeLinker: pnpm, enabledGlobalCache: false and enableMirror: false set, on running yarn install, the globalFolder is populated with cached files when I would not expect it to be.

To reproduce

package.json

{
  "name": "yarn-pnpm-test",
  "dependencies": {
    "typescript": "5.7.3"
  },
  "packageManager": "yarn@4.9.2"
}

.yarnrc.yml

nodeLinker: pnpm
enableGlobalCache: false
enableMirror: false
globalFolder: ./.yarn/global-cache

Script

#!/bin/bash

GLOBAL_CACHE_DIR='./.yarn/global-cache'
rm -rf $GLOBAL_CACHE_DIR
rm -rf node_modules
yarn install
# Report the number of files in the global cache
find $GLOBAL_CACHE_DIR -type f | wc -l

This reports 130 files in the global-cache dir

Changing the nodeLinker to pnp or node-modules and re-running the script both report only 1 file in the global-cache dir as expected.

Environment

System:
    OS: macOS 15.3.2
    CPU: (12) arm64 Apple M2 Pro
  Binaries:
    Node: 22.16.0 - /private/var/folders/pz/q84_my554js504tv_6w4g1gh0000gp/T/xfs-7bfe9783/node
    Yarn: 4.9.2 - /private/var/folders/pz/q84_my554js504tv_6w4g1gh0000gp/T/xfs-7bfe9783/yarn
    npm: 10.9.2 - ~/.nvm/versions/node/v22.16.0/bin/npm
    bun: 1.1.42 - /opt/homebrew/bin/bun

Additional context

No response