cacheable-request - fix: keyv error listener leak on every request

[jaredwray]

Please check if the PR fulfills these requirements

• Followed the Contributing guidelines and Code of Conduct
• Tests for the changes have been added (for bug fixes/features) with 100% code coverage.

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

Bug fix — fixes #1685.

cacheable-request registered its per-request Keyv error handler with cachek.once("error", errorHandler) and later tried to clean it up with cachek.removeListener("error", errorHandler). Keyv v5's custom event manager wraps once() listeners in an anonymous function and removeListener() matches by exact reference, so the wrapper was never removed — one error listener leaked per request, triggering MaxListenersExceededWarning: Possible event memory leak detected. 101 error listeners added. after 100 requests. This is a regression of the original leak fix (jaredwray/cacheable-request#222 / #223) after the Keyv 5 migration.

Changes in packages/cacheable-request/src/index.ts:

• Register the handler with cachek.on("error", errorHandler) so the shared removeListener cleanup removes the exact same reference. Effective once-semantics are preserved: forwarding a Keyv error emits error on the request emitter, which itself removes the Keyv listener.
• Also remove the handler on the underlying request's error, abort, and close events, so aborted or destroyed requests that never emit response/error on the emitter no longer leak the listener.

Tests (packages/cacheable-request/test/cacheable-request-instance.test.ts):

• New regression test asserting the Keyv error listener count returns to baseline after sequential requests across both the network and cached-response paths (fails with 6 leaked listeners before the fix).
• New regression test asserting the listener is removed when the request is aborted before a response (fails with 1 leaked listener before the fix).
• Verified the exact reproduction script from cacheable-request leaks Keyv error listeners on every request with Keyv v5 #1685 against the built package: after 110 sequential requests there are 0 residual listeners and no MaxListenersExceededWarning.

pnpm test for the package passes (67 tests; statements/lines remain at 100%, branch coverage improves 93.97% → 96.38%). The only failure in this environment is the pre-existing return with url and port test, which requires outbound network access to mockhttp.org and fails identically on unmodified main here.

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https://claude.ai/code/session_011tF3VefnzwcH6TQo48uJHQ

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Generated by Claude Code

[gemini-code-assist]

Code Review

This pull request addresses a memory leak where Keyv error listeners were not being properly unregistered upon request completion or abortion. It introduces a unified cleanup handler registered across multiple termination events and adds corresponding unit tests. The reviewer identified a potential issue where registering once listeners on the underlying request object without cleaning them up when the request succeeds could still lead to dangling listeners and a memory leak, and provided a code suggestion to clean up those listeners on any termination path.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (d93554f) to head (43aec20).

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #1687   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files           29        29           
  Lines         3504      3513    +9     
  Branches       794       809   +15     
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+ Hits          3504      3513    +9     

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