fix: eliminate Promise.race handler-stacking in batchPackageStream#600
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John-David Dalton (jdalton) merged 4 commits intomainfrom Apr 21, 2026
Merged
fix: eliminate Promise.race handler-stacking in batchPackageStream#600John-David Dalton (jdalton) merged 4 commits intomainfrom
John-David Dalton (jdalton) merged 4 commits intomainfrom
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The prior implementation stored per-generator promises in a Map and called `Promise.race(running.values())` every loop iteration. Each race call re-attached fresh `.then` handlers to every still-pending promise in the pool, so long-surviving generators accumulated O(iterations) dead handler closures before finally settling. See nodejs/node#17469 and https://github.com/cefn/watchable/tree/main/packages/unpromise for the pattern. Switch to a single-waiter queue: each generator's `.then` delivers its step into a buffer, and the main loop awaits a fresh promiseWithResolvers each iteration. Handlers are one-shot — nothing to stack. All 565 tests pass.
Pairs with the batchPackageStream fix: documents the anti-pattern so future code does not reintroduce it. Concise bullet in the SHARED STANDARDS section alongside the existsSync rule.
The rule already lives in SHARED STANDARDS (line 26). Having it twice — once general, once under sdk-specific TypeScript Patterns — adds maintenance drift without adding clarity. Keep the SHARED STANDARDS version.
…ckageStream Align the single-waiter queue with project rules: alphabetical destructuring/type property order and undefined (not null) for absent state.
Bill Li (billxinli)
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Apr 20, 2026
John-David Dalton (jdalton)
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Apr 21, 2026
Replace the 6-line comment landed in #600 with the fuller narrative that was sitting uncommitted on the fix/promise-race-leak worktree — concrete walkthrough of the handler-stacking trap, what each piece of the single-waiter machinery is responsible for, and why the snapshot-and- clear dance in deliverStep/deliverError matters. No behavioral change; comments only. The mechanical fix already shipped in #600 (376a743); this captures the reasoning someone will want when they look at this code six months from now.
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John-David Dalton (jdalton)
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* docs(claude): consolidate CLAUDE.md rules from stale branches
Fold the genuinely valuable guidance scattered across several now-stale
worktree branches (fix/promise-race-leak, chore/parallel-claude-rule,
docs/claude-fix-warnings-rule) into a single coherent pass on CLAUDE.md,
and pull in two rules the socket-repo-template gold standard already
carries but this repo was missing.
- Restructure the Promise.race guidance into a dedicated "### Promise.race
in loops" subsection with the template's Safe/Leaky/Fix triad — same
content, but the three-state framing is easier to apply at review time
than a single run-on bullet.
- Add null-prototype rule: `{ __proto__: null, ...rest }` is already the
idiom used throughout src/socket-sdk-class.ts and src/file-upload.ts
(config objects, internal state, return shapes); codify it so new
contributions follow suit and prototype pollution surface stays small.
- Add Linear-reference rule: keep code and PR history tool-agnostic.
Forward-looking — no violations currently in the repo.
Deliberately NOT pulled from template: the "NEVER use dynamic imports"
rule. SDK uses `await import('node:fs')` legitimately in two places
(socket-sdk-class.ts:1931, :3818) for lazy loading; a blanket ban would
be wrong here.
* docs(sdk): expand batchPackageStream Promise.race rationale
Replace the 6-line comment landed in #600 with the fuller narrative that
was sitting uncommitted on the fix/promise-race-leak worktree — concrete
walkthrough of the handler-stacking trap, what each piece of the
single-waiter machinery is responsible for, and why the snapshot-and-
clear dance in deliverStep/deliverError matters.
No behavioral change; comments only. The mechanical fix already shipped
in #600 (376a743); this captures the reasoning someone will want when
they look at this code six months from now.
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Summary
src/socket-sdk-class.ts):batchPackageStreamre-raced a persistent pool of generator promises each iteration. EveryPromise.race(running.values())call attached a fresh.then(resolve, reject)pair to every still-pending arm, so long-running generators accumulatedO(iterations_survived)dead handler closures before finally settling. See nodejs/node#17469 and @watchable/unpromise for the pattern..thendelivers its step into a buffer, and the main loop awaits a freshpromiseWithResolverseach iteration. Handlers are one-shot — nothing to stack. Rejection and ordering semantics preserved.CLAUDE.md): added a concise rule under SHARED STANDARDS so the pattern is not reintroduced.Test plan
pnpm test)pnpm run check(lint + type-check) clean