fix(react-call): end-all no longer drops same-tick calls

[desko27]

What

Fixes a real library bug: calling the end-all form X.end() (no target promise) and then X.call({...}) one or more times in the same synchronous tick resulted in the new calls never rendering — the stack ended up empty even though call() ran after end(). No error was thrown.

const onClick = () => {
  Upload.end()                                  // end all (stack may be empty — intended no-op)
  for (const file of files) Upload.call({ ... }) // ← these used to vanish
}

Reproduced in the web gallery (React 19) while building examples; the broadcast-update example had been rewritten to avoid the pattern as a workaround.

Root cause

The end-all path used null as a "match everything" sentinel for its deferred removal:

// createEnd, end-all case
storeRef.current.set(null, /* mark all ended */)
setTimeout(() => storeRef.current.remove(null), unmountingDelay) // ← scheduled for NEXT macrotask

// store.remove, with promise === null
stack = stack.filter((c) => promise && c.promise !== promise)    // null && … → keeps NOTHING

So end() scheduled a blanket "clear the entire stack" for the next macrotask. Calls added after end() in the same tick were appended first, then wiped when the deferred remove(null) fired. Removing the leading end() removed the scheduled wipe — hence the calls rendered.

The targeted path (end(promise, value)) was never affected: it only filters out the one matching promise. update() (update-all) was never affected either: it mutates in place and schedules no removal.

The fix

createEnd now captures the exact set of promises it resolves during its synchronous set() pass, and defers removal of only those. The null sentinel is gone from the store — remove takes a Set<Promise> and filters with !promises.has(c.promise). Calls added later in the same tick are never in the captured set, so they survive. Targeted end() passes a one-element set and behaves exactly as before.

See ADR-0020 for the decision and the rejected alternatives.

Tests

New regression block same tick as later call() in end.test.tsx, covering all three interactions called out during triage — each flushes the unmountingDelay macrotask before asserting (the bug only manifested after the deferred removal ran):

• end-all then call() ×3 → 3 render (the exact repro; was 0 before the fix)
• end-all with pre-existing calls → the old calls are removed, the later ones kept
• targeted end(promise) then call() → the targeted call is removed, later ones survive
• update() then call() → all survive

Full suite green: 132 unit + 5 dist tests, tsc -b clean, biome clean, size-limit holds (main.js 810 B / main.cjs 895 B, both under the 1 KB budget).

Release

Patch changeset for react-call included, so merging to main opens/updates the "Version Packages" PR via the release workflow.

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Project	Deployment	Actions	Updated (UTC)
react-call	Ready	Preview, Comment	May 30, 2026 10:51pm