stream: do cleanup when iterator is destroyed

[KhooHaoYit]

When you create a readable.iterator from a stream with options.destroyOnReturn on false, the iterator doesn't do any cleanup when the iterator exits, causing it to add multiple listeners to the stream

Code that reproduces the bug

constpass=newstream.PassThrough().end();for(letamount=15;amount;--amount){forawait(constchunkofpass.iterator({destroyOnReturn: false})){}}

Console output

(node:20524) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 readable listeners added to [PassThrough]. Use emitter.setMaxListeners() to increase limit (Use `node --trace-warnings ...` to show where the warning was created) (node:20524) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 end listeners added to [PassThrough]. Use emitter.setMaxListeners() to increase limit (node:20524) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 finish listeners added to [PassThrough]. Use emitter.setMaxListeners() to increase limit (node:20524) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 error listeners added to [PassThrough]. Use emitter.setMaxListeners() to increase limit (node:20524) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 close listeners added to [PassThrough]. Use emitter.setMaxListeners() to increase limit 

Tested node version

v17.6.0 on Windows 10 and v18.0.0-pre @ b481beecd8

[nodejs-github-bot]

Review requested:

• @nodejs/streams

[mcollina]

Can you please add a unit test?

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/42978/

[benjamingr]

@Linkgoron

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/43020/

[mcollina]

lgtm

[nodejs-github-bot]

Commit Queue failed

- Loading data for nodejs/node/pull/42320 ✔ Done loading data for nodejs/node/pull/42320 ----------------------------------- PR info ------------------------------------ Title stream: do cleanup when iterator is destroyed (#42320) ⚠ Could not retrieve the email or name of the PR author's from user's GitHub profile! Branch KhooHaoYit:stream-iterator-fix -> nodejs:master Labels stream, commit-queue-squash Commits 3 - stream: do cleanup when iterator is destroyed - test: check for dangling listeners - test: enable no-unused-vars ESLint rule Committers 1 - Khoo Hao Yit <[email protected]> PR-URL: https://github.com/nodejs/node/pull/42320 Reviewed-By: Robert Nagy Reviewed-By: Matteo Collina Reviewed-By: Nitzan Uziely Reviewed-By: Benjamin Gruenbaum Reviewed-By: James M Snell ------------------------------ Generated metadata ------------------------------ PR-URL: https://github.com/nodejs/node/pull/42320 Reviewed-By: Robert Nagy Reviewed-By: Matteo Collina Reviewed-By: Nitzan Uziely Reviewed-By: Benjamin Gruenbaum Reviewed-By: James M Snell -------------------------------------------------------------------------------- ℹ This PR was created on Sun, 13 Mar 2022 11:59:44 GMT ✔ Approvals: 5 ✔ - Robert Nagy (@ronag) (TSC): https://github.com/nodejs/node/pull/42320#pullrequestreview-908129087 ✔ - Matteo Collina (@mcollina) (TSC): https://github.com/nodejs/node/pull/42320#pullrequestreview-910068802 ✔ - Nitzan Uziely (@linkgoron): https://github.com/nodejs/node/pull/42320#pullrequestreview-908140795 ✔ - Benjamin Gruenbaum (@benjamingr): https://github.com/nodejs/node/pull/42320#pullrequestreview-908141108 ✔ - James M Snell (@jasnell) (TSC): https://github.com/nodejs/node/pull/42320#pullrequestreview-908891052 ✖ This PR needs to wait 15 more minutes to land ✔ Last GitHub CI successful ℹ Last Full PR CI on 2022-03-14T17:01:15Z: https://ci.nodejs.org/job/node-test-pull-request/43020/ - Querying data for job/node-test-pull-request/43020/ ✔ Last Jenkins CI successful -------------------------------------------------------------------------------- ✔ Aborted `git node land` session in /home/runner/work/node/node/.ncu

https://github.com/nodejs/node/actions/runs/1986430799

[nodejs-github-bot]

Landed in 6d3920d