fix(path-checker): resolve workspace aliases and filter URLs

[adelin-b]

Summary

• Resolve workspace package aliases in the path checker instead of flagging them as MISSING_PATH errors. In monorepos, references like @acme/ui or @acme/shared/utils in scaffold files are valid import aliases, not filesystem paths.
• Filter URLs (http://, https://) which were being treated as filesystem paths because they contain /.

How it works

1. require.resolve first — tries Node's built-in module resolution for installed npm packages (handles node_modules packages regardless of hoisting strategy)
2. Workspace name fallback — reads the root package.json workspaces field, globs each pattern, and collects the name from each workspace's package.json. This handles package managers like bun that don't symlink all workspaces into node_modules/
3. URL filter — skips http:// and https:// prefixed values before path checking

Example

A monorepo with this structure:

packages/ui/package.json    → { "name": "@acme/ui" }
packages/shared/package.json → { "name": "@acme/shared" }

Previously, scaffold references like @acme/ui/button or @acme/shared/types would trigger:

✗ MISSING_PATH: Referenced path does not exist: @acme/ui/button

Now they resolve correctly via the workspace name lookup.

Test plan

• All 83 existing tests pass
• Build succeeds
• Tested against a real Turborepo + bun monorepo with 8 workspace packages — all @scope/* aliases now resolve correctly
• npm packages in node_modules still resolve via require.resolve
• URLs no longer flagged as missing paths

[theDakshJaitly]

Thanks for the contribution! The approach is solid: clean separation with collectWorkspaceNames, good normalization of the workspaces field, and the require.resolve → workspace fallback chain is well-structured.

A few things to address before merging:

HIGH: pnpm workspace support missing

The JSDoc says "Works with any package manager (npm, yarn, pnpm, bun)" but pnpm uses pnpm-workspace.yaml, not the workspaces field in package.json. This means pnpm monorepos will get an empty workspace set and still produce false-positive MISSING_PATH errors.

Fix: Either parse pnpm-workspace.yaml as a fallback when patterns is empty, or update the comment to exclude pnpm.

MEDIUM: URL regex only covers http/https

URL_PATTERN won't catch ftp://, file:///, or protocol-relative // URLs. Consider broadening to:

const URL_PATTERN = /^(?:https?|ftp|file):\/\//;

MEDIUM: createRequire anchor path

createRequire(resolve(projectRoot, "package.json")) works incidentally but the canonical pattern is createRequire(resolve(projectRoot, "noop.js")) or using pathToFileURL(), since createRequire expects a module filename.

LOW: No tests for new behavior

There are no tests for the path checker module at all. Would be great to add coverage for at least: URL skipping, require.resolve resolution, and workspace name resolution.

[advancedresearcharray]

Addressed all review feedback in https://github.com/advancedresearcharray/mex/commit/72efcdf (branch fix/skip-scoped-packages-and-urls).

Changes

HIGH — pnpm workspace support

• Added collectWorkspacePatterns() that falls back to parsing pnpm-workspace.yaml when the root package.json has no workspaces field (or it is empty).
• Updated JSDoc to document both resolution paths.

MEDIUM — URL regex

• Broadened URL_PATTERN to ^(?:https?|ftp|file):\/\/|^\/\/ so ftp://, file:///, and protocol-relative // URLs are skipped.

MEDIUM — createRequire anchor

• Switched from createRequire(resolve(projectRoot, "package.json")) to createRequire(resolve(projectRoot, "noop.js")).

LOW — Tests

• Added 4 tests covering URL skipping, package.json workspace alias resolution, pnpm-workspace.yaml resolution, and require.resolve for installed scoped packages.

All 87 tests pass; tsc --noEmit clean.

@adelin-b — could you cherry-pick or merge 72efcdf into this branch when you have a moment? I don't have push access to your fork.

[advancedresearcharray]

Review feedback is implemented on branch fix/skip-scoped-packages-and-urls at advancedresearcharray/mex@6617ed6.

@adelin-b — to update this PR in one step, merge adelin-b/mex#1 (review fixes into your fix/skip-scoped-packages-and-urls branch). Alternatively, cherry-pick 6617ed6.

All four review items are covered:

• pnpm pnpm-workspace.yaml fallback when package.json has no workspaces
• broader URL filter (ftp://, file:///, protocol-relative //)
• canonical createRequire(resolve(projectRoot, "noop.js")) anchor
• 4 new path-checker tests (87 total passing, typecheck clean)

[advancedresearcharray]

Updated commit (no co-author trailers): advancedresearcharray/mex@fdbb507.

Merge via adelin-b/mex#1 when ready.

[advancedresearcharray]

All four review items are addressed in commit fdbb507 on branch fix/skip-scoped-packages-and-urls.

Review responses

HIGH — pnpm workspace support
Added collectWorkspacePatterns() that reads root package.json workspaces first, then falls back to pnpm-workspace.yaml when that field is absent or empty.

MEDIUM — URL regex
URL_PATTERN is now ^(?:https?|ftp|file):\/\/|^\/\/ so ftp://, file:///, and protocol-relative // URLs are skipped.

MEDIUM — createRequire anchor
Switched to createRequire(resolve(projectRoot, "noop.js")).

LOW — Tests
Added four path-checker tests: URL skipping, package.json workspace aliases, pnpm-workspace.yaml resolution, and require.resolve for installed scoped packages.

All 87 tests pass; tsc --noEmit clean.

Updating this PR

The fix branch lives on advancedresearcharray/mex. Because maintainer_can_modify is enabled, @theDakshJaitly you can update this PR's branch directly:

git fetch https://github.com/advancedresearcharray/mex.git fix/skip-scoped-packages-and-urls
git push https://github.com/adelin-b/mex.git FETCH_HEAD:fix/skip-scoped-packages-and-urls

Alternatively, @adelin-b can merge adelin-b/mex#1, or merge #68 which contains the same commits ready for review.

[theDakshJaitly]

Thanks @adelin-b for the original fix here. The four review items (pnpm-workspace.yaml support, broader URL filter, canonical createRequire anchor, and tests) were all addressed and just merged as #68, which builds directly on your branch and commits. Closing this as superseded by #68 - the feature is now on main. Appreciate the contribution.