Add support for --workspaces to run on all npm workspaces

[voxpelli]

I'm thinking it would be neat to be able to do:

run-p --workspaces check:*

Related issues:

• Support a --workspaces and maybe --workspace flag to run in a npm workspace monorepo voxpelli/node-installed-check#31
• Support a --workspaces and maybe --workspace flag to run in a npm workspace monorepo dependency-check-team/dependency-check#188

Interesting modules:

• https://github.com/voxpelli/read-workspaces
• https://www.npmjs.com/package/@npmcli/map-workspaces
• https://www.npmjs.com/package/yarn-changed-workspaces

[bcomnes]

Makes sense now that npm supports workspaces.

[voxpelli]

When --max-parallel is set, should it try to spread out the executions across the workspaces or just assemble a long list of all tasks to be run and execute them from top to bottom?

The latter would be more a 1:1 between run-s --workspaces and run-p --workspaces but I kind of like the idea of balancing it across the different workspaces. Probably overengineering to do though, right?

[bcomnes]

Probably do what ever is simplest to implement and maintain.

[voxpelli]

I'm going to give it a stab now

[bcomnes]

If you do take a stab at this, feel free to refactor ancient promise callbacks to async await etc. Whatever cleans it up.

[voxpelli]

Created a helper for reading all packages from a workspace, with similar filtering as npm itself has: https://github.com/voxpelli/read-workspaces

Started using it in list-installed and as such also in installed-check / installed-check-core now