fix(promise): record error before signalling channel in all()

[abnegate]

Problem

The Swoole Coroutine adapter's all() rejection handler signals the coordination Channel before assigning $error:

}, function ($err) use ($channel, &$error) {
    $channel->push(true);          // <- signals first
    if ($error === null) {
        $error = $err;             // <- assigns after
    }
});

The awaiting coroutine's while ($ticks--) $channel->pop() loop can drain the channel and evaluate if ($error !== null) while $error is still null, so all() resolves instead of rejecting — violating the documented contract ("rejects when any input promise rejects").

This is timing-dependent: branches that reject after a coroutine yield (the realistic async case, e.g. an API call that sleeps then throws) reliably expose it, especially under scheduler pressure from other concurrent coroutines.

Fix

Assign $error before pushing to the channel — matching the ordering already used by the success handler in all() and by both handlers in allSettled().

Test

Adds an E2e regression (testAllRejectsWhenABranchRejectsAfterYielding) with an async branch that sleeps then throws alongside a slower-resolving sibling. It fails deterministically against the old ordering (all() resolves) and passes with the fix. Full Swoole Promise E2e suite: 24/24 green. Pint PSR-12 clean.

🤖 Generated with Claude Code

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[greptile-apps]

Greptile Summary

This PR fixes a timing-dependent bug in Coroutine::all() where the rejection handler pushed to the coordination channel before assigning $error, allowing the awaiting coroutine to drain the channel and observe a still-null error — causing all() to resolve instead of reject. The fix swaps the two lines so $error is recorded first, consistent with the success handler and with allSettled().

• src/Promise/Adapter/Swoole/Coroutine.php — core ordering fix in all(); also corrects an incidental undefined-class reference in race() where new PromiseException(...) (no import, would fatal at runtime on an empty-array call) is replaced with new Promise(...) (Utopia\\Async\\Exception\\Promise, already imported and used by any()/all()).
• src/Parallel/Pool/Swoole/Process.php — adds a kill($pid, 0) existence probe each non-reap iteration to drain stale PIDs from $pidsToWait, with an early-exit once the set is empty; the timeout kill loop also probes before sending SIGKILL.
• src/Timer/Adapter/Sync.php — removes the now-redundant $running array and replaces the dual-check tick loop with while ($this->doExists($timerId)), which is equivalent since doExists checks isset($this->timers[$timerId]) and the adapter is fully synchronous.

Confidence Score: 5/5

Safe to merge — the change is a minimal, targeted reorder of two lines with a deterministic regression test that fails before the fix and passes after it.

The all() fix is correct and tightly scoped. The incidental fixes (undefined PromiseException in race(), dead-PID cleanup in Process, Sync tick simplification) are all improvements with no regressions. The new E2e test exercises the exact failure mode described in the PR.

No files require special attention.

Important Files Changed

Filename	Overview
src/Promise/Adapter/Swoole/Coroutine.php	Core fix: records $error before channel push in all() to eliminate the race; also corrects an undefined-class reference in race() (PromiseException → Promise)
src/Parallel/Pool/Swoole/Process.php	Adds dead-PID cleanup probe (kill $pid, 0) each iteration when no child is reaped, and breaks early once pidsToWait empties; timeout kill loop also probes before sending SIGKILL
src/Timer/Adapter/Sync.php	Simplifies doTick: removes separate $running array and replaces dual-check with a single doExists loop; behaviour is equivalent because Sync is fully synchronous
tests/E2e/Promise/Swoole/CoroutineTest.php	Adds deterministic regression test for the all() ordering bug using two async branches that each sleep then resolve/reject

_{Reviews (2): Last reviewed commit: "fix: resolve PHPStan level-max errors in..." | Re-trigger Greptile}

[github-actions]

Benchmark Results

Swoole Adapters (Sync, Swoole Thread, Swoole Process, Amp, React)

╔══════════════════════════════════════════════════════════════════════════════╗
║                    Parallel Adapter Benchmark                                ║
╚══════════════════════════════════════════════════════════════════════════════╝

System Info:
  PHP Version: 8.4.22
  Swoole Version: 6.1.3
  CPU Cores: 4
  Iterations: 10 per test
  Load: 50% (workload intensity)

Detected adapters:
  [x] Sync
  [x] Swoole Thread
  [x] Swoole Process
  [x] Amp
  [x] React
  [x] ext-parallel

┌──────────────────────────────────────────────────────────────────────────────┐
│ CPU-Intensive Workloads                                                      │
└──────────────────────────────────────────────────────────────────────────────┘

  Prime calculation (4 tasks, primes up to 200000)
--------------------------------------------------------------------------------

ext-parallel Adapter (Sync, Amp, React, ext-parallel)

╔══════════════════════════════════════════════════════════════════════════════╗
║                    Parallel Adapter Benchmark                                ║
╚══════════════════════════════════════════════════════════════════════════════╝

System Info:
  PHP Version: 8.4.22
  CPU Cores: 4
  Iterations: 10 per test
  Load: 50% (workload intensity)

Detected adapters:
  [x] Sync
  [ ] Swoole Thread
  [ ] Swoole Process
  [x] Amp
  [x] React
  [x] ext-parallel

┌──────────────────────────────────────────────────────────────────────────────┐
│ CPU-Intensive Workloads                                                      │
└──────────────────────────────────────────────────────────────────────────────┘

  Prime calculation (4 tasks, primes up to 200000)
--------------------------------------------------------------------------------
  Sync:             0.396s (std: 0.017s, range: 0.382-0.432s)
  Amp:              0.242s (std: 0.047s, range: 0.182-0.353s)  1.63x speedup
  React:            0.323s (std: 0.044s, range: 0.284-0.392s)  1.22x speedup
  ext-parallel:     0.183s (std: 0.009s, range: 0.171-0.196s)  2.16x speedup
  Winner: ext-parallel (53.6% faster than sync)

  Matrix multiply (4 tasks, 200x200)
--------------------------------------------------------------------------------
  Sync:             1.149s (std: 0.008s, range: 1.142-1.171s)
  Amp:              0.453s (std: 0.045s, range: 0.432-0.575s)  2.54x speedup
  React:            0.571s (std: 0.044s, range: 0.501-0.612s)  2.01x speedup
  ext-parallel:     0.442s (std: 0.010s, range: 0.434-0.466s)  2.60x speedup
  Winner: ext-parallel (61.5% faster than sync)

┌──────────────────────────────────────────────────────────────────────────────┐
│ I/O-Simulated Workloads                                                      │
└──────────────────────────────────────────────────────────────────────────────┘

  Sleep tasks (4 tasks, 50ms each)
--------------------------------------------------------------------------------
  Sync:             0.200s (std: 0.000s, range: 0.200-0.200s)
  Amp:              0.067s (std: 0.048s, range: 0.051-0.204s)  3.00x speedup
  React:            0.115s (std: 0.001s, range: 0.115-0.116s)  1.74x speedup
  ext-parallel:     0.053s (std: 0.007s, range: 0.050-0.073s)  3.79x speedup
  Winner: ext-parallel (73.6% faster than sync)

  Mixed workload (4 tasks)
--------------------------------------------------------------------------------
  Sync:             0.135s (std: 0.001s, range: 0.132-0.138s)
  Amp:              0.064s (std: 0.042s, range: 0.051-0.183s)  2.11x speedup
  React:            0.114s (std: 0.001s, range: 0.113-0.114s)  1.19x speedup
  ext-parallel:     0.058s (std: 0.010s, range: 0.050-0.084s)  2.33x speedup
  Winner: ext-parallel (57.1% faster than sync)

┌──────────────────────────────────────────────────────────────────────────────┐
│ Scaling Benchmarks                                                           │
└──────────────────────────────────────────────────────────────────────────────┘

  Scaling test (1 tasks)
--------------------------------------------------------------------------------
  Sync:             0.040s (std: 0.000s, range: 0.040-0.040s)
  Amp:              0.041s (std: 0.019s, range: 0.035-0.094s)  0.96x speedup
  React:            0.079s (std: 0.002s, range: 0.074-0.082s)  0.50x speedup
  ext-parallel:     0.043s (std: 0.007s, range: 0.040-0.063s)  0.93x speedup
  Winner: Amp (-3.8% faster than sync)

  Scaling test (2 tasks)
--------------------------------------------------------------------------------
  Sync:             0.075s (std: 0.002s, range: 0.074-0.080s)
  Amp:              0.047s (std: 0.028s, range: 0.038-0.127s)  1.58x speedup
  React:            0.081s (std: 0.001s, range: 0.080-0.083s)  0.92x speedup
  ext-parallel:     0.043s (std: 0.007s, range: 0.040-0.064s)  1.76x speedup
  Winner: ext-parallel (43.0% faster than sync)

  Scaling test (4 tasks)
--------------------------------------------------------------------------------
  Sync:             0.149s (std: 0.001s, range: 0.148-0.150s)
  Amp:              0.080s (std: 0.036s, range: 0.051-0.179s)  1.86x speedup
  React:            0.163s (std: 0.047s, range: 0.131-0.232s)  0.91x speedup
  ext-parallel:     0.053s (std: 0.007s, range: 0.051-0.074s)  2.79x speedup
  Winner: ext-parallel (64.2% faster than sync)

  Scaling test (8 tasks)
--------------------------------------------------------------------------------
  Sync:             0.296s (std: 0.002s, range: 0.295-0.300s)
  Amp:              0.131s (std: 0.039s, range: 0.101-0.232s)  2.26x speedup
  React:            0.309s (std: 0.048s, range: 0.261-0.367s)  0.96x speedup
  ext-parallel:     0.105s (std: 0.008s, range: 0.102-0.128s)  2.83x speedup
  Winner: ext-parallel (64.7% faster than sync)
   16 tasks: Sync=0.475s, Amp=0.261s (1.8x), React=0.542s (0.9x), parallel=0.206s (2.3x)
   32 tasks: Sync=0.927s, Amp=0.523s (1.8x), React=1.044s (0.9x), parallel=0.410s (2.3x)

┌──────────────────────────────────────────────────────────────────────────────┐
│ Summary                                                                      │
└──────────────────────────────────────────────────────────────────────────────┘

  Adapter             Wins  Avg Speedup  Max Speedup
----------------------------------------------------
  Amp                    1        1.95x        3.00x
  React                  0        1.12x        2.01x
  ext-parallel           9        2.38x        3.79x

  Recommendation: ext-parallel for best overall performance.
  Theoretical max speedup: 4x (limited by CPU cores)

Benchmarks run with 10 iterations on GitHub Actions runner