[yuxi-liu-wired]

processNextTick kept state across tasks of one queue. So a task that threw left every later task REJECTED, and a reject handler that returned a value never set it back to RESOLVED. (p/resolved nil) returns one shared NULL_PROMISE, so independent chains from nil share a queue and one chain's exception corrupts the others.

Reproduction

const a = P.resolved(null).then(() => { throw new Error("A"); });
const b = P.resolved(null).then(() => "b-ok");
a.catch(() => null);

const c = P.resolved(null).then(() => { throw new Error("C"); })
  .catch(e => "recovered:" + e.message).then(v => v + ":continued");
const d = P.resolved(null).then(() => "d-ok");

	11.0.678	master (before)	this PR (after)
b	rejected A	resolved null	"b-ok"
c	"recovered:C:continued"	rejected "recovered:C"	"recovered:C:continued"
d	rejected C	resolved null	"d-ok"

Fix

• state/rvalue are task-local. Each outcome depends only on the source promise and the task's own handler: return means RESOLVED (a reject handler that returns is a recovery), throw means REJECTED.
• handle uses defaultRejectHandler again (as in 11.0.678). Its identity reject handler only worked because the loop-level state leaked.
• A task whose reject handler is defaultRejectHandler gets the rethrow outcome directly, with no throw. This avoids a ~2.5× slowdown in handle on rejected promises. Benchmarks (1M ops, 15 interleaved rounds): resolved and rejected paths match master within noise, and rejection propagation through .then/.catch is ~2× faster (655 → 314 ms).

Tests

New :cljs tests in core_test.cljc: independent-chains-from-nil-do-not-share-outcome and throw-in-then-recover-in-catch-and-continue. Both fail on master (3 assertions) and pass with the fix.

• CLJS: 82 tests, 281 assertions, 0 failures (ClojureScript 1.12.42 via cljs.main, since Clojars was unreachable from the environment the change was made in; the CI job runs the shadow-cljs build).
• JVM (all promesa.tests.*-test): 92 tests, 263 assertions, 0 failures.
• bb (bb test:bb): 68 tests, 160 assertions, 0 failures.

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