Summary

• route request socket-only failures through
  eq.destroy(err) so Axios rejects instead of leaving the error outside the request promise chain
• remove the per-request socket error listener on
  eq.close so reused keep-alive sockets do not accumulate listeners
• add focused adapter regressions for socket-only request errors and keep-alive listener cleanup

Notes

• Alternative to fix(http): handle socket errors to prevent EPIPE crashes #10561 for issue Failed requests can sometimes crash the Node.js process with EPIPE. #10558; this version addresses the unresolved review concern about leaking socket.error listeners on keep-alive reuse.
• Direct behavioral validation passed locally with targeted inline Node checks covering socket-only rejection, listener cleanup across reused sockets, and the existing keep-alive timeout path.

Closes #10558

Summary by cubic

Ensure axios rejects when a request’s socket emits an error, and prevent keep-alive listener leaks by removing per-request socket error listeners on close. Adds unit tests for the socket-only error path and listener cleanup. Addresses #10558.

Description

• Route socket-only errors through req.destroy(err) so requests reject.
• Add a per-request socket.on('error', ...) and remove it on req.once('close', ...) to avoid leaks on reused keep-alive sockets.
• Matches Node keep-alive behavior and prevents unhandled socket errors during reuse.

Testing

• Added tests in tests/unit/adapters/http.test.js:
  • Rejects when only the request socket emits an error.
  • Confirms socket error listeners are removed after each keep-alive request (listener count stays constant).

^{Written for commit 77eef87. Summary will update on new commits.}