module: show user location for missing module errors, resolve #38892

[meixg]

Fixes: #38892

Summary

This improves the source location shown for uncaught missing module errors.

Previously, some missing module failures displayed an internal loader location at the top of the fatal exception output, such as node:internal/modules/..., instead of pointing at the user import, dynamic import(), or require()
expression that triggered the resolution failure.

This change decorates missing module errors with an arrow message that points to the user source location.

Covered cases:

• static ESM import
• dynamic import()
• CommonJS require()

Implementation

For static ESM imports, ModuleWrap#getModuleRequests() now exposes the line and column for each module request. The ESM linking path uses that information when decorating ERR_MODULE_NOT_FOUND.

For dynamic import(), the loader temporarily increases Error.stackTraceLimit around the synchronous getOrCreateModuleJob() call so the original ERR_MODULE_NOT_FOUND stack can retain the user import frame. The decorator then uses
that frame to locate the dynamic import expression.

For CommonJS, MODULE_NOT_FOUND decoration uses the current structured stack to find the parent module call site, avoiding parsing the formatted err.stack string.

The source snippet formatting is centralized in internal/errors/error_source.js, including clipping for long source lines.

Example

Before:

node:internal/modules/cjs/loader:...
  throw err;
  ^

Error: Cannot find module 'this-package-does-not-exist'

After:

/path/to/entry.cjs:2
const missing = require("this-package-does-not-exist");
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^

Error: Cannot find module 'this-package-does-not-exist'

Tests

Added coverage for:

• static ESM import missing package errors
• dynamic import missing package errors from both .mjs and .cjs
• CommonJS require missing package errors
• long-line source snippet clipping

Relevant tests:

• test/es-module/test-esm-module-not-found-error-location.mjs
• test/es-module/test-esm-dynamic-import-not-found-error-location.mjs
• test/parallel/test-module-not-found-error-location.js

[nodejs-github-bot]

Review requested:

• @nodejs/loaders
• @nodejs/vm

[codecov]

Codecov Report

❌ Patch coverage is 92.70517% with 24 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.64%. Comparing base (53b8d3c) to head (2142429).
⚠️ Report is 18 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/internal/modules/esm/module_job.js	86.07%	11 Missing ⚠️
lib/internal/modules/esm/loader.js	93.93%	5 Missing and 1 partial ⚠️
lib/internal/errors/error_source.js	95.00%	4 Missing ⚠️
lib/internal/modules/cjs/loader.js	95.31%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #62885      +/-   ##
==========================================
+ Coverage   89.62%   89.64%   +0.01%     
==========================================
  Files         706      706              
  Lines      219137   219492     +355     
  Branches    41981    42065      +84     
==========================================
+ Hits       196404   196763     +359     
- Misses      14614    14617       +3     
+ Partials     8119     8112       -7     

Files with missing lines	Coverage Δ
src/module_wrap.cc	74.56% <100.00%> (+0.14%)	⬆️
lib/internal/modules/cjs/loader.js	98.06% <95.31%> (-0.09%)	⬇️
lib/internal/errors/error_source.js	86.12% <95.00%> (+4.30%)	⬆️
lib/internal/modules/esm/loader.js	99.15% <93.93%> (-0.54%)	⬇️
lib/internal/modules/esm/module_job.js	95.07% <86.07%> (-1.33%)	⬇️

... and 38 files with indirect coverage changes

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