module: add requireStack to all error paths

[Han5991]

@BridgeAR

Summary

Previously, requireStack was only attached to MODULE_NOT_FOUND errors
thrown from the final fallback path in Module._resolveFilename. Several
earlier error paths in the resolution pipeline silently omitted it:

Error path	Had requireStack?
_resolveFilename final fallback	✅
tryPackage — invalid package.json main field	❌
trySelf — self-referential package resolution	❌
createEsmNotFoundErr — ESM-in-CJS resolution	❌

This meant that callers catching MODULE_NOT_FOUND errors could not
reliably use err.requireStack for diagnostics across all failure modes.

Changes

lib/internal/modules/cjs/loader.js

• Moves requireStack construction before all resolution attempts in
  _resolveFilename, so it is always available when an error is thrown.
• Wraps trySelf and Module._findPath in try/catch blocks that
  attach requireStack to any MODULE_NOT_FOUND error that does not
  already have one. The e.requireStack === undefined guard prevents
  overwriting a value set by a future inner code path.
• Adds an optional requireStack parameter to createEsmNotFoundErr
  and passes it from the #-import error site in _resolveFilename.

test/sequential/test-module-loading.js

• Extends the existing missing-main-no-index assertion to verify that
  requireStack is present on the error thrown from tryPackage.

test/parallel/test-module-loading-error.js

• Extends the existing is-dir assertion to verify that requireStack
  is present on a standard MODULE_NOT_FOUND error.

Reproduction

Before this fix, the requireStack property was undefined for errors
thrown from tryPackage:

try {
  require('./a-package-with-bad-main'); // package.json main → missing file
} catch (e) {
  console.log(e.code);         // 'MODULE_NOT_FOUND'
  console.log(e.requireStack); // undefined  ← bug
}

After this fix:

console.log(e.requireStack); // ['/path/to/caller.js']

Testing

python3 tools/test.py test/sequential/test-module-loading.js
python3 tools/test.py test/parallel/test-module-loading-error.js

Related

- Resolves the TODO left by @BridgeAR in tryPackage:
// TODO(BridgeAR): Add the requireStack as well.
- Resolves the TODO left by @BridgeAR in createEsmNotFoundErr:
// TODO(BridgeAR): Add the requireStack as well.

[nodejs-github-bot]

Review requested:

• @nodejs/loaders

[codecov]

Codecov Report

❌ Patch coverage is 96.87500% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 89.65%. Comparing base (6a3d358) to head (7b29458).
⚠️ Report is 8 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/internal/modules/cjs/loader.js	96.87%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #62059      +/-   ##
==========================================
+ Coverage   89.58%   89.65%   +0.07%     
==========================================
  Files         674      676       +2     
  Lines      205159   206259    +1100     
  Branches    39352    39501     +149     
==========================================
+ Hits       183792   184924    +1132     
+ Misses      13583    13469     -114     
- Partials     7784     7866      +82     

Files with missing lines	Coverage Δ
lib/internal/modules/cjs/loader.js	98.33% <96.87%> (-0.04%)	⬇️

... and 127 files with indirect coverage changes

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