electron-forge does not work with npm workspaces (npm v7)

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• I agree to follow the code of conduct that this project follows, as appropriate.
• I have searched the issue tracker for a bug that matches the one I want to file, without success.

Issue Details

• Electron Forge Version: 6.0.0-beta.57
• Electron Version: 13.1.0
• Operating System: macOS 11.4
• Last Known Working Electron Forge version:: N/A

Expected Behavior

Running electron-forge start from project root (npm run start --workspace="packages/electron-app") or from electron workspace root (cd packages/electron-app && npm run start) should be able to locate the electron executable in the project root node_modules.

Actual Behavior

Running electron-forge start throws a PackageNotFoundError:

An unhandled rejection has occurred inside Forge:
PackageNotFoundError: Cannot find the package "electron". Perhaps you need to run "yarn install" in "<path-to-project-root>/packages/electron-app"?

To Reproduce

Minimal repro example: https://github.com/brightbrained/electron-forge-workspaces

Make sure to have npm v7 or above for workspaces support (npm install --global npm@latest)

git clone https://github.com/brightbrained/electron-forge-workspaces.git
cd electron-forge-workspaces
npm install
npm run start --workspace="packages/electron"

Additional Information

[robin-hartmann]

Here’s a working app using NPM workspaces: https://github.com/jeanbmar/black-moon-rewind/tree/r0.1-beta/packages/launcher In order to get Forge working til the end, I had to write my own dependency resolver (np-bundle) and call it in Forge hooks because electron-packager won’t resolve monorepo deps.

I also had to set packagerConfig: { prune: false } in my forge config file, but then your bundler worked.

Thank you very much!

[jeanbmar]

Here’s a working app using NPM workspaces: https://github.com/jeanbmar/black-moon-rewind/tree/r0.1-beta/packages/launcher In order to get Forge working til the end, I had to write my own dependency resolver (np-bundle) and call it in Forge hooks because electron-packager won’t resolve monorepo deps.