fix: treat private class methods as function boundaries in TLA detection

[burgerni10]

Problem

detectESMFeatures climbs up from each AwaitExpression / for await and stops at function boundaries. The check lists FunctionDeclaration, FunctionExpression, ArrowFunctionExpression, ObjectMethod and ClassMethod, but not ClassPrivateMethod. So await inside async #method() is reported as top-level await.

If the module also has export statements, the transformer logs "has both top-level await and export statements" and returns the source untransformed. Bytecode generation then fails and the file is skipped from the executable. The binary crashes at runtime, e.g. ERR_MODULE_NOT_FOUND from a sibling import.

Real-world trigger: node-opcua ≥ 2.184 (node-opcua-chunkmanager, node-opcua-server, node-opcua-pki, node-opcua-certificate-manager, …) uses private async methods, so any app bundling it gets a broken executable with pkg 6.22.0.

Fix

Replace the list of checks with parent.isFunction(). Babel's Function alias covers all function-like nodes, including ClassPrivateMethod, so no future function kind can slip through.

Tests

• New unit test: await / for await inside private methods of an exported class. It fails before the change and passes after.
• yarn test:unit (258 pass) and yarn lint are clean.
• Checked on a real app (OIBus, node-opcua 2.186.1, node26-macos-arm64): the warnings are gone and the executable starts.

🤖 Generated with Claude Code

[burgerni10]

I only noticed now that PR #300 fix it another way. Sorry for this duplicate, you can close this PR if you think the other fix is better

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.47%. Comparing base (36f18af) to head (ffa3726).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #307      +/-   ##
==========================================
- Coverage   87.23%   86.47%   -0.77%     
==========================================
  Files          23       23              
  Lines        7929     7917      -12     
  Branches     1214     1213       -1     
==========================================
- Hits         6917     6846      -71     
- Misses       1005     1063      +58     
- Partials        7        8       +1     

Files with missing lines	Coverage Δ
lib/esm-transformer.ts	88.38% <100.00%> (+0.37%)	⬆️

... and 2 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[robertsLando]

not needed

[burgerni10]

tests on ubuntu-latest 22.x and 24.x were failing without it : https://github.com/yao-pkg/pkg/actions/runs/36423145365

I've removed it anyway since you pinned node-opcua to 2.181.0 in tests.

I directly edited my commit

[Copilot]

Copilot review overview

🟢 Approval recommended

The generalized Babel function-boundary check correctly addresses the regression and has focused unit coverage.

Review effort: Balanced
Findings: None

What changed in this PR

Fixes false top-level-await detection for private class methods.

Changes:

• Uses Babel’s function alias for all function boundaries.
• Adds regression coverage for private async methods.
• Defines import.meta paths in the node-opcua bundle test.

File	Description
lib/​esm-transformer.ts	Uses isFunction() during await detection.
test/​unit/​esm-transformer.test.ts	Tests private methods containing await expressions.
test/​test-80-compression-node-opcua/​main.js	Supplies CJS-compatible import.meta definitions.

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.