rings-core 0.20.0

Chord DHT implementation with ICE
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
use std::sync::atomic::AtomicBool;
use std::sync::atomic::AtomicUsize;
use std::sync::atomic::Ordering;

use bytes::Bytes;
use futures::channel::oneshot;

use super::capacity::OUTBOUND_DATA_RESERVED_TRANSFERS;
use super::*;
use crate::ecc::SecretKey;
use crate::message::e2e::E2eHandshakeRequest;
use crate::message::Message;

type TestTransfer = (TransferClass, &'static str);

struct ShutdownProbe {
    admitted: Arc<AtomicUsize>,
    sender: Option<oneshot::Sender<usize>>,
}

impl Drop for ShutdownProbe {
    fn drop(&mut self) {
        let previous = self.admitted.fetch_sub(1, Ordering::AcqRel);
        assert!(previous > 0, "a shutdown probe must own one admission");
    }
}

struct ShutdownProbeCompletion {
    admitted: Arc<AtomicUsize>,
    sender: oneshot::Sender<usize>,
}

struct ImplicitCompletionProbe {
    admitted: Arc<AtomicUsize>,
    sender: Option<oneshot::Sender<usize>>,
}

impl Drop for ImplicitCompletionProbe {
    fn drop(&mut self) {
        if let Some(sender) = self.sender.take() {
            let _ = sender.send(self.admitted.load(Ordering::Acquire));
        }
    }
}

struct ImplicitCapacityProbe(Arc<AtomicUsize>);

impl Drop for ImplicitCapacityProbe {
    fn drop(&mut self) {
        let previous = self.0.fetch_sub(1, Ordering::AcqRel);
        assert_eq!(previous, 1, "the active transfer must own one admission");
    }
}

impl ShutdownProbeCompletion {
    fn publish(self) {
        let _ = self.sender.send(self.admitted.load(Ordering::Acquire));
    }
}

fn finalize_shutdown_probe(mut probe: ShutdownProbe) -> Option<ShutdownProbeCompletion> {
    let sender = probe.sender.take()?;
    let admitted = probe.admitted.clone();
    drop(probe);
    Some(ShutdownProbeCompletion { admitted, sender })
}

fn pop_and_finish(queues: &mut TransferQueues<TestTransfer>) -> Option<&'static str> {
    let transfer = queues.pop()?;
    let class = transfer.class();
    let (_, item) = transfer.into_item();
    queues.record_frame_admitted(class);
    queues.finish_current(class);
    Some(item)
}

fn pop_order(mut queues: TransferQueues<TestTransfer>, n: usize) -> Vec<&'static str> {
    let mut order = Vec::new();
    for _ in 0..n {
        let Some(item) = pop_and_finish(&mut queues) else {
            break;
        };
        order.push(item);
    }
    order
}

fn push(queues: &mut TransferQueues<TestTransfer>, class: TransferClass, item: &'static str) {
    queues.push(class, (class, item));
}

fn assert_wire_classification(
    message: &Message,
    expected_kind: &'static str,
    expected_class: TransferClass,
) {
    let typed = OutboundMessageKind::from_message(message);
    let wire = rings_codec::serialize(message).expect("message must serialize");
    let decoded = OutboundMessageKind::from_wire(&wire).expect("wire metadata must decode");

    assert_eq!(typed.as_str(), expected_kind);
    assert_eq!(typed.class(), expected_class);
    assert_eq!(decoded, typed);
    assert_eq!(decoded.class(), typed.class());
}

#[test]
fn test_detached_first_frame_success_and_cancellation_are_mutually_exclusive() {
    let cancelled = DetachedAdmission::new();
    let cancelled_stop = cancelled.stop_token();
    assert_eq!(cancelled.cancel(), DetachedAdmissionCancel::Cancelled);
    assert!(cancelled.try_mark_irrevocable().is_none());
    assert!(!cancelled.try_succeed());
    assert!(cancelled_stop.should_stop());

    let succeeded = DetachedAdmission::new();
    let succeeded_stop = succeeded.stop_token();
    assert!(succeeded.try_mark_irrevocable().is_some());
    assert!(succeeded.try_succeed());
    assert!(succeeded.try_mark_irrevocable().is_some());
    assert_eq!(succeeded.cancel(), DetachedAdmissionCancel::MustAwait);
    assert!(!succeeded_stop.should_stop());

    let irrevocable = DetachedAdmission::new();
    let irrevocable_stop = irrevocable.stop_token();
    assert!(irrevocable.try_mark_irrevocable().is_some());
    assert_eq!(irrevocable.cancel(), DetachedAdmissionCancel::MustAwait);
    assert!(!irrevocable_stop.should_stop());
}

fn admit_single_frame_transfer(
    queues: &mut TransferQueues<TestTransfer>,
    delivery_id: u64,
) -> &'static str {
    let active = queues.pop().expect("a runnable transfer must exist");
    let class = active.class();
    let label = active.item().1;
    queues.record_frame_admitted(class);
    queues.wait_for_delivery(delivery_id, active);
    let delivered = queues
        .take_waiting(class, delivery_id)
        .expect("the matching delivery must own the lane head");
    queues.make_runnable(delivered);
    let completion_probe = queues.pop().expect("completion probe must be runnable");
    assert_eq!(completion_probe.item().1, label);
    queues.finish_current(class);
    label
}

#[test]
fn test_dht_control_preempts_queued_bulk_work() {
    let mut queues = TransferQueues::default();
    push(&mut queues, TransferClass::Application, "app-1");
    push(&mut queues, TransferClass::Application, "app-2");
    push(&mut queues, TransferClass::DhtControl, "dht");

    assert_eq!(pop_and_finish(&mut queues), Some("dht"));
}

#[test]
fn test_continuous_dht_control_yields_to_lower_classes() {
    let mut queues = TransferQueues::default();
    for item in ["dht-1", "dht-2", "dht-3", "dht-4", "dht-5"] {
        push(&mut queues, TransferClass::DhtControl, item);
    }
    push(&mut queues, TransferClass::Application, "app");

    assert_eq!(pop_order(queues, 6), vec![
        "dht-1", "dht-2", "dht-3", "dht-4", "app", "dht-5"
    ]);
}

#[test]
fn test_completion_probes_do_not_consume_control_frame_burst() {
    let mut queues = TransferQueues::default();
    for item in ["dht-1", "dht-2", "dht-3", "dht-4", "dht-5"] {
        push(&mut queues, TransferClass::DhtControl, item);
    }
    push(&mut queues, TransferClass::Application, "app");

    let mut admitted = Vec::new();
    for delivery_id in 0..3 {
        admitted.push(admit_single_frame_transfer(&mut queues, delivery_id));
    }

    let active = queues.pop().expect("fourth control transfer must exist");
    assert_eq!(active.item().1, "dht-4");
    let class = active.class();
    queues.record_frame_admitted(class);
    admitted.push(active.item().1);
    queues.wait_for_delivery(3, active);
    let delivered = queues
        .take_waiting(TransferClass::DhtControl, 3)
        .expect("fourth control delivery must resume its lane");
    queues.make_runnable(delivered);

    admitted.push(pop_and_finish(&mut queues).expect("application frame must receive its slot"));
    let completed_control = queues
        .pop()
        .expect("fourth control completion probe must remain runnable");
    assert_eq!(completed_control.item().1, "dht-4");
    queues.finish_current(completed_control.class());
    admitted.push(admit_single_frame_transfer(&mut queues, 4));

    assert_eq!(admitted, vec![
        "dht-1", "dht-2", "dht-3", "dht-4", "app", "dht-5"
    ]);
}

#[test]
fn test_lower_classes_progress_round_robin() {
    let mut queues = TransferQueues::default();
    push(&mut queues, TransferClass::Storage, "storage-1");
    push(&mut queues, TransferClass::Storage, "storage-2");
    push(&mut queues, TransferClass::E2e, "e2e");
    push(&mut queues, TransferClass::Application, "app");

    assert_eq!(pop_order(queues, 4), vec![
        "storage-1",
        "e2e",
        "app",
        "storage-2"
    ]);
}

#[test]
fn test_every_transfer_class_uses_its_own_lane() {
    let classes = [
        TransferClass::DhtControl,
        TransferClass::Storage,
        TransferClass::E2e,
        TransferClass::Application,
    ];
    let mut queues = TransferQueues::default();
    for class in classes {
        push(&mut queues, class, "indexed-lane");
    }

    for _ in classes {
        let transfer = queues.pop().expect("every indexed lane must be reachable");
        assert_eq!(transfer.class(), transfer.item().0);
        queues.finish_current(transfer.class());
    }
}

#[test]
fn test_lower_cursor_wraps_and_skips_idle_lanes() {
    for (previous, expected) in [
        (TransferClass::Application, TransferClass::Storage),
        (TransferClass::Storage, TransferClass::E2e),
        (TransferClass::E2e, TransferClass::Application),
    ] {
        let mut queues = TransferQueues::default();
        queues.record_frame_admitted(previous);
        for class in [
            TransferClass::Storage,
            TransferClass::E2e,
            TransferClass::Application,
        ] {
            push(&mut queues, class, "round-robin");
        }
        assert_eq!(
            queues.pop().map(|transfer| transfer.class()),
            Some(expected)
        );
    }

    let mut sparse = TransferQueues::default();
    sparse.record_frame_admitted(TransferClass::Storage);
    push(&mut sparse, TransferClass::Application, "sparse");
    assert_eq!(
        sparse.pop().map(|transfer| transfer.class()),
        Some(TransferClass::Application)
    );
}

#[test]
fn test_terminal_attempt_advances_the_lower_class_cursor() {
    let mut queues = TransferQueues::default();
    push(&mut queues, TransferClass::Storage, "stale-storage");
    push(&mut queues, TransferClass::E2e, "e2e");
    push(&mut queues, TransferClass::Application, "application");

    let stale = queues
        .pop()
        .expect("storage must start at the initial cursor");
    assert_eq!(stale.item().1, "stale-storage");
    queues.fail_attempt(stale);
    push(&mut queues, TransferClass::Storage, "more-stale-storage");

    let next = queues
        .pop()
        .expect("a failed attempt must yield to the next lower class");
    assert_eq!(next.item().1, "e2e");
}

#[test]
fn test_cancelled_control_attempts_consume_the_control_burst() {
    let mut queues = TransferQueues::default();
    push(&mut queues, TransferClass::Application, "application");
    for index in 0..OUTBOUND_CONTROL_BURST {
        push(&mut queues, TransferClass::DhtControl, "cancelled-control");
        let control = queues
            .pop()
            .expect("control must run while its burst remains");
        assert_eq!(
            control.item().1,
            "cancelled-control",
            "control attempt {index}"
        );
        queues.fail_attempt(control);
    }
    push(&mut queues, TransferClass::DhtControl, "fifth-control");

    let next = queues
        .pop()
        .expect("lower work must run after failed control consumes the burst");
    assert_eq!(next.item().1, "application");
}

#[test]
fn test_waiting_lane_preserves_same_class_fifo_and_allows_control_preemption() {
    let mut queues = TransferQueues::default();
    push(&mut queues, TransferClass::Application, "app-1");
    push(&mut queues, TransferClass::Application, "app-2");

    let active = queues.pop().expect("first application transfer must exist");
    assert_eq!(active.item(), &(TransferClass::Application, "app-1"));
    queues.record_frame_admitted(TransferClass::Application);
    queues.wait_for_delivery(7, active);
    push(&mut queues, TransferClass::DhtControl, "dht");
    let resumed = queues
        .take_waiting(TransferClass::Application, 7)
        .expect("matching application delivery must resume the lane");
    queues.make_runnable(resumed);

    assert_eq!(pop_and_finish(&mut queues), Some("dht"));
    assert_eq!(pop_and_finish(&mut queues), Some("app-1"));
    assert_eq!(pop_and_finish(&mut queues), Some("app-2"));
}

#[test]
fn test_draining_a_waiting_lane_returns_its_active_and_queued_transfers() {
    let mut queues = TransferQueues::default();
    push(&mut queues, TransferClass::Application, "app-1");
    push(&mut queues, TransferClass::Application, "app-2");

    let active = queues
        .pop()
        .expect("active transfer must exist before drain");
    queues.record_frame_admitted(TransferClass::Application);
    queues.wait_for_delivery(11, active);

    let mut drained: Vec<_> = queues
        .drain_transfers()
        .into_iter()
        .map(|(_, label)| label)
        .collect();
    drained.sort_unstable();
    assert_eq!(drained, vec!["app-1", "app-2"]);
}

#[test]
fn test_removing_ready_items_preserves_waiting_heads_and_fifo_order() {
    let mut queues = TransferQueues::default();
    push(&mut queues, TransferClass::Application, "waiting");
    push(&mut queues, TransferClass::Application, "cancel-1");
    push(&mut queues, TransferClass::Application, "keep");
    push(&mut queues, TransferClass::Application, "cancel-2");
    let waiting = queues.pop().expect("lane head must be runnable");
    queues.wait_for_delivery(17, waiting);

    let removed = queues.remove_ready_where(|(_, label)| label.starts_with("cancel"));

    assert_eq!(
        removed
            .into_iter()
            .map(|(_, label)| label)
            .collect::<Vec<_>>(),
        vec!["cancel-1", "cancel-2"]
    );
    let waiting = queues
        .take_waiting(TransferClass::Application, 17)
        .expect("active delivery must remain owned by the lane");
    queues.finish_current(TransferClass::Application);
    assert_eq!(waiting.item().1, "waiting");
    assert_eq!(pop_and_finish(&mut queues), Some("keep"));
}

#[test]
fn test_transfer_capacity_is_strict_across_permit_lifetimes() {
    let global = Arc::new(GlobalTransferCapacity::new());
    let capacity = Arc::new(TransferCapacity::new(global));
    let peer = Did::from(7_u32);
    let mut permits = Vec::with_capacity(OUTBOUND_TRANSFER_QUEUE_CAPACITY);
    for _ in 0..OUTBOUND_DATA_TRANSFER_CAPACITY {
        permits.push(
            capacity
                .try_acquire(peer, TransferClass::Application, 1)
                .expect("non-control capacity must admit its declared bound"),
        );
    }

    assert!(matches!(
        capacity.try_acquire(peer, TransferClass::Application, 1),
        Err(Error::OutboundTransferCapacityExceeded {
            peer: error_peer,
            capacity: OUTBOUND_DATA_TRANSFER_CAPACITY,
        }) if error_peer == peer
    ));
    for _ in 0..OUTBOUND_CONTROL_RESERVED_TRANSFERS {
        permits.push(
            capacity
                .try_acquire(peer, TransferClass::DhtControl, 1)
                .expect("reserved control capacity must remain available"),
        );
    }
    for class in [TransferClass::Storage, TransferClass::E2e] {
        for _ in 0..OUTBOUND_DATA_RESERVED_TRANSFERS {
            permits.push(
                capacity
                    .try_acquire(peer, class, 1)
                    .expect("every data class retains its reserved capacity"),
            );
        }
    }
    assert!(matches!(
        capacity.try_acquire(peer, TransferClass::DhtControl, 1),
        Err(Error::OutboundTransferCapacityExceeded {
            peer: error_peer,
            capacity,
        }) if error_peer == peer
            && capacity == super::capacity::transfer_limit(TransferClass::DhtControl)
    ));
    let backpressure = Error::OutboundTransferCapacityExceeded {
        peer,
        capacity: OUTBOUND_TRANSFER_QUEUE_CAPACITY,
    };
    assert!(backpressure.is_deferrable_data_plane_send());
    assert!(!backpressure.records_peer_send_failure());
    permits.pop();
    assert!(capacity.try_acquire(peer, TransferClass::E2e, 1).is_ok());
}

#[test]
fn test_transfer_memory_capacity_is_weighted_and_released() {
    let global = Arc::new(GlobalTransferCapacity::new());
    let capacity = Arc::new(TransferCapacity::new(global));
    let peer = Did::from(9_u32);
    let data_limit = super::capacity::peer_byte_limit(TransferClass::Application);
    let permit = capacity
        .try_acquire(peer, TransferClass::Application, data_limit)
        .expect("one transfer may consume the non-control byte budget");

    assert_eq!(capacity.admitted_bytes(), data_limit);
    assert!(matches!(
        capacity.try_acquire(peer, TransferClass::Application, 1),
        Err(Error::OutboundTransferMemoryCapacityExceeded {
            peer: error_peer,
            requested_bytes: 1,
            capacity_bytes,
        }) if error_peer == peer && capacity_bytes == data_limit
    ));
    drop(permit);
    assert_eq!(capacity.admitted_bytes(), 0);
}

#[test]
fn test_shutdown_closes_channel_without_worker_owned_sender() {
    let (sender, mut receiver) = mailbox::channel();
    let stop = StopSource::new();
    let handle = OutboundPeerHandle {
        state: Arc::new(OutboundPeerState {
            #[cfg(all(feature = "dummy", not(target_family = "wasm")))]
            peer: Did::from(42_u32),
            sender,
            cancel_requested: Arc::new(AtomicBool::new(false)),
            _capacity_anchor: TransferCapacityAnchor::new(Arc::new(TransferCapacity::new(
                Arc::new(GlobalTransferCapacity::new()),
            ))),
            stop: stop.clone(),
        }),
    };

    handle.shutdown();

    assert!(stop.is_stop_requested());
    assert!(matches!(receiver.next().now_or_never(), Some(None)));
}

#[test]
fn test_worker_drop_stops_generation_and_closes_ingress_without_a_normal_run_exit() {
    let peer = Did::from(43_u32);
    let (sender, receiver) = mailbox::channel();
    let stop = StopSource::new();
    let (measurements, _measurement_receiver) = MeasurementRecorder::channel(None, peer);
    let worker = OutboundWorker::new(
        receiver,
        stop.clone(),
        measurements,
        peer,
        Arc::new(AtomicBool::new(false)),
    );

    drop(worker);

    assert!(stop.is_stop_requested());
    assert!(sender
        .send(OutboundCommand::CancelStopped, MailboxLane::Priority)
        .is_err());
}

#[cfg(not(target_family = "wasm"))]
#[tokio::test]
async fn test_worker_drop_allows_registry_to_replace_the_stopped_generation() {
    let schedulers = OutboundSchedulers::new(None);
    let peer = Did::from(44_u32);
    let capacity = schedulers
        .lock_registry()
        .capacity(peer, &schedulers.global_capacity);
    let (sender, receiver) = mailbox::channel();
    let stop = StopSource::new();
    let stale = OutboundPeerHandle {
        state: Arc::new(OutboundPeerState {
            #[cfg(all(feature = "dummy", not(target_family = "wasm")))]
            peer,
            sender,
            cancel_requested: Arc::new(AtomicBool::new(false)),
            _capacity_anchor: TransferCapacityAnchor::new(capacity),
            stop: stop.clone(),
        }),
    };
    schedulers.lock_registry().peers.insert(peer, stale.clone());
    let (measurements, _measurement_receiver) = MeasurementRecorder::channel(None, peer);
    let worker = OutboundWorker::new(
        receiver,
        stop,
        measurements,
        peer,
        Arc::new(AtomicBool::new(false)),
    );

    drop(worker);
    let replacement = schedulers
        .handle(peer)
        .expect("a stopped worker generation must be replaceable");

    assert!(!Arc::ptr_eq(&stale.state, &replacement.state));
    assert!(!replacement.state.stop.is_stop_requested());
    schedulers.shutdown(peer);
}

#[test]
fn test_shutdown_batch_finalizes_active_ready_and_buffered_before_first_publish() {
    let admitted = Arc::new(AtomicUsize::new(3));
    let (active_sender, active_receiver) = oneshot::channel();
    let (ready_sender, ready_receiver) = oneshot::channel();
    let (buffered_sender, buffered_receiver) = oneshot::channel();
    let active = ShutdownProbe {
        admitted: admitted.clone(),
        sender: Some(active_sender),
    };
    let ready = ShutdownProbe {
        admitted: admitted.clone(),
        sender: Some(ready_sender),
    };
    let buffered = ShutdownProbe {
        admitted: admitted.clone(),
        sender: Some(buffered_sender),
    };

    let completions = ShutdownBatch::new(vec![active], vec![ready], vec![buffered])
        .finalize(finalize_shutdown_probe);
    assert_eq!(admitted.load(Ordering::Acquire), 0);
    let mut completions = completions.into_iter();
    completions
        .next()
        .expect("active completion must be collected first")
        .publish();
    assert_eq!(active_receiver.now_or_never(), Some(Ok(0)));
    completions
        .next()
        .expect("ready completion must remain available")
        .publish();
    assert_eq!(ready_receiver.now_or_never(), Some(Ok(0)));
    completions
        .next()
        .expect("buffered completion must remain available")
        .publish();
    assert_eq!(buffered_receiver.now_or_never(), Some(Ok(0)));
    assert!(completions.next().is_none());
}

#[test]
fn test_active_transfer_drop_releases_capacity_before_implicit_completion() {
    let admitted = Arc::new(AtomicUsize::new(1));
    let (sender, receiver) = oneshot::channel();
    let scheduled = ScheduledTransfer::new(
        ImplicitCompletionProbe {
            admitted: admitted.clone(),
            sender: Some(sender),
        },
        ImplicitCapacityProbe(admitted.clone()),
    );

    drop(scheduled);

    assert_eq!(receiver.now_or_never(), Some(Ok(0)));
    assert_eq!(admitted.load(Ordering::Acquire), 0);
}

#[test]
fn test_final_handle_drop_requests_stop_before_channel_close() {
    let (sender, mut receiver) = mailbox::channel();
    let stop = StopSource::new();
    let handle = OutboundPeerHandle {
        state: Arc::new(OutboundPeerState {
            #[cfg(all(feature = "dummy", not(target_family = "wasm")))]
            peer: Did::from(42_u32),
            sender,
            cancel_requested: Arc::new(AtomicBool::new(false)),
            _capacity_anchor: TransferCapacityAnchor::new(Arc::new(TransferCapacity::new(
                Arc::new(GlobalTransferCapacity::new()),
            ))),
            stop: stop.clone(),
        }),
    };

    drop(handle);

    assert!(stop.is_stop_requested());
    assert!(matches!(receiver.next().now_or_never(), Some(None)));
}

#[test]
fn test_message_classification_is_local_and_control_first() {
    let dht = Message::PeerLivenessProbe(crate::message::PeerLivenessProbe { sent_at_ms: 1 });
    let storage = Message::SyncEntriesWithSuccessor(crate::message::SyncEntriesWithSuccessor {
        purpose: crate::dht::StorageSyncPurpose::AdditiveRepair,
        destination: crate::dht::StorageSyncDestination::PhysicalOwner(Did::from(1_u32)),
        data: Vec::new(),
    });
    let requester_public_key = SecretKey::random().pubkey();
    let e2e = Message::E2eHandshakeRequest(E2eHandshakeRequest::new(requester_public_key));
    let query = Message::QueryForTopoInfoSend(crate::message::QueryForTopoInfoSend::new_for_sync(
        Did::from(2_u32),
    ));
    let chunk = Message::Chunk(crate::chunk::Chunk {
        chunk: [0, 1],
        data: Bytes::new(),
        meta: crate::chunk::ChunkMeta::default(),
    });
    let app = Message::custom(b"hello").expect("custom message must build");

    assert_wire_classification(&dht, "PeerLivenessProbe", TransferClass::DhtControl);
    assert_wire_classification(&storage, "SyncEntriesWithSuccessor", TransferClass::Storage);
    assert_wire_classification(&app, "CustomMessage", TransferClass::Application);
    assert_wire_classification(&e2e, "E2eHandshakeRequest", TransferClass::E2e);
    assert_wire_classification(&query, "QueryForTopoInfoSend", TransferClass::DhtControl);
    assert_wire_classification(&chunk, "Chunk", TransferClass::Application);
}

#[cfg(not(target_family = "wasm"))]
#[tokio::test]
async fn test_peer_capacity_survives_scheduler_generation_replacement() {
    let schedulers = OutboundSchedulers::new(None);
    let peer = Did::from(11_u32);
    let first = schedulers
        .handle(peer)
        .expect("first scheduler generation must start");
    let mut permits = Vec::with_capacity(OUTBOUND_DATA_TRANSFER_CAPACITY);
    for _ in 0..OUTBOUND_DATA_TRANSFER_CAPACITY {
        permits.push(
            first
                .reserve(peer, TransferClass::Application, 1)
                .expect("first generation must fill its declared capacity"),
        );
    }

    schedulers.shutdown(peer);
    let replacement = schedulers
        .handle(peer)
        .expect("replacement scheduler generation must start");

    assert!(matches!(
        replacement.reserve(peer, TransferClass::Application, 1),
        Err(Error::OutboundTransferCapacityExceeded {
            peer: error_peer,
            capacity: OUTBOUND_DATA_TRANSFER_CAPACITY,
        }) if error_peer == peer
    ));
    permits.pop();
    assert!(replacement
        .reserve(peer, TransferClass::Application, 1)
        .is_ok());
}

#[cfg(not(target_family = "wasm"))]
#[tokio::test]
async fn test_dead_peer_capacity_keys_are_pruned() {
    let schedulers = OutboundSchedulers::new(None);
    let first = schedulers
        .reserve(Did::from(41_u32), TransferClass::Application, 1)
        .await
        .expect("first peer must reserve capacity");
    assert_eq!(schedulers.capacity_key_count_for_test(), 1);
    drop(first);

    let second = schedulers
        .reserve(Did::from(42_u32), TransferClass::Application, 1)
        .await
        .expect("second peer must reserve capacity");
    assert_eq!(schedulers.capacity_key_count_for_test(), 1);
    drop(second);
    schedulers.shutdown(Did::from(42_u32));

    assert_eq!(schedulers.capacity_key_count_for_test(), 0);
}

#[cfg(not(target_family = "wasm"))]
#[tokio::test]
async fn test_peer_state_keeps_idle_capacity_accountant_alive() {
    let schedulers = OutboundSchedulers::new(None);
    let peer = Did::from(43_u32);
    let handle = schedulers.handle(peer).expect("peer worker must start");
    let permit = schedulers
        .reserve(peer, TransferClass::Application, 1)
        .await
        .expect("peer must reserve capacity");

    drop(permit);
    assert_eq!(schedulers.capacity_key_count_for_test(), 1);

    drop(handle);
    schedulers.shutdown(peer);
    assert_eq!(schedulers.capacity_key_count_for_test(), 0);
}