fix(ls): suppress false UNMET DEPENDENCYs in linked strategy

[manzoorwanijk]

In continuation of our exploration of using install-strategy=linked in the Gutenberg monorepo, which powers the WordPress Block Editor.

In linked install strategy, npm ls reports two types of false UNMET DEPENDENCYs:

1. Undeclared workspaces: The root node always creates workspace edges for all workspaces (from the workspaces field in package.json), but in linked mode only workspaces explicitly declared in dependencies are hoisted to root/node_modules/. Undeclared workspaces are intentionally absent, yet npm ls reports them as missing.

2. devDependencies of store packages: Store package link targets (at .store/<key>/node_modules/<name>) have no parent in the node tree, so they are treated as "top" nodes and their devDependencies are loaded as edges. Those devDeps are never installed, but npm ls --all reports them as UNMET DEPENDENCY.

This PR adds a filterLinkedStrategyEdges filter in ls.js that is only active when installStrategy === 'linked'. It skips workspace edges for undeclared workspaces at the root level and skips dev edges for non-root packages (store packages).

References

Fixes #9090
Fixes #9092

[wraithgar]

I think this approach is cleaner than what we're doing with things like this.#rootDeclaredDeps in makeIdealGraph.

    this.#rootDeclaredDeps = new Set([
      ...Object.keys(rootPkg.dependencies || {}),
      ...(!omit.has('dev') ? Object.keys(rootPkg.devDependencies || {}) : []),
      ...(!omit.has('optional') ? Object.keys(rootPkg.optionalDependencies || {}) : []),
      ...(!omit.has('peer') ? Object.keys(rootPkg.peerDependencies || {}) : []),
    ])

could become

    this.#rootDeclaredDeps = new Set(Object.keys(Object.assign({},
      rootPkg.dependencies,
      (!omit.has('dev') && rootPkg.devDependencies),
      (!omit.has('optional') && rootPkg.optionalDependencies),
      (!omit.has('peer') && rootPkg.peerDependencies),
    )))

[manzoorwanijk]

Yes! That refactor in isolated-reifier.js would be a nice follow-up.

[manzoorwanijk]

Or should I make that change here? It doesn't seem to affect the coverage, so the changes should be minimal.

[manzoorwanijk]

Updated in #9097