[rush] preferredVersions doesn't work when subspace is enabled.

[fzxen]

Summary

I am trying to enable subspace in my repo by flowing the doc. Then discovered a problem: After enabling the subspace feature, the preferredVersions in common-version will not take effect.

Details

when subspace is disable, rush will create a file named as pnpmfileSettings.json including preferredVersions.

https://github.com/microsoft/rushstack/blob/e64a1e51976626f95250205cbb9d21b5fc805769/libraries/rush-lib/src/logic/pnpm/IPnpmfile.ts#L13-L22

Then, pnpmfile.cjs read preferredVersions from pnpmfileSettings.json and it can set the preferred versions on the dependency map

https://github.com/microsoft/rushstack/blob/e64a1e51976626f95250205cbb9d21b5fc805769/libraries/rush-lib/src/logic/pnpm/PnpmfileShim.ts#L82-L103

However, when subspace is enable, pnpmfileSettings.json no longer contains preferredVersion information

https://github.com/microsoft/rushstack/blob/e64a1e51976626f95250205cbb9d21b5fc805769/libraries/rush-lib/src/logic/pnpm/IPnpmfile.ts#L34-L39

rush create a file named as global-pnpmfile.cjs and it doesn't seem to implement any logic related to preferredVersions.

https://github.com/microsoft/rushstack/blob/e64a1e51976626f95250205cbb9d21b5fc805769/libraries/rush-lib/src/logic/pnpm/SubspaceGlobalPnpmfileShim.ts#L34-L64

Subspace does not support preferredVersions, does it?

Standard questions

Please answer these questions to help us investigate your issue more quickly:

Question	Answer
@microsoft/rush globally installed version?	5.147.2
rushVersion from rush.json?	5.147.2
useWorkspaces from rush.json?	Yes
Operating system?	Mac
Would you consider contributing a PR?	Yes
Node.js version (node -v)?	v20.16.0

[fzxen]

After debugging rush-lib, I found that pnpmfileSettings.json will be written twice.

First time: https://github.com/microsoft/rushstack/blob/438525caf08bcbdb75d33f6747cc34e050837d46/libraries/rush-lib/src/logic/pnpm/PnpmfileConfiguration.ts#L80-L83

Second time: https://github.com/microsoft/rushstack/blob/438525caf08bcbdb75d33f6747cc34e050837d46/libraries/rush-lib/src/logic/pnpm/SubspacePnpmfileConfiguration.ts#L50-L56

The second write operation will overwrite the first write content. And pnpmfileSettings.json is read once by global-pnpmfile.cjs and pnpmfile.cjs respectively.

Maybe we should distinguish the file names written twice, one is named pnpmfileSettings.json and the other named is globalPnpmfileSettings.json.

[ivanmjartan]

@fzxen Hi I have facing same problem, do you have found some workaround?