1use super::*;
2use clock::ReplicaId;
3use rand::prelude::*;
4use std::{
5 cmp::Ordering,
6 env,
7 iter::Iterator,
8 time::{Duration, Instant},
9};
10
11#[cfg(test)]
12#[ctor::ctor]
13fn init_logger() {
14 // std::env::set_var("RUST_LOG", "info");
15 env_logger::init();
16}
17
18#[test]
19fn test_edit() {
20 let mut buffer = Buffer::new(0, 0, History::new("abc".into()));
21 assert_eq!(buffer.text(), "abc");
22 buffer.edit(vec![3..3], "def");
23 assert_eq!(buffer.text(), "abcdef");
24 buffer.edit(vec![0..0], "ghi");
25 assert_eq!(buffer.text(), "ghiabcdef");
26 buffer.edit(vec![5..5], "jkl");
27 assert_eq!(buffer.text(), "ghiabjklcdef");
28 buffer.edit(vec![6..7], "");
29 assert_eq!(buffer.text(), "ghiabjlcdef");
30 buffer.edit(vec![4..9], "mno");
31 assert_eq!(buffer.text(), "ghiamnoef");
32}
33
34#[gpui::test(iterations = 100)]
35fn test_random_edits(mut rng: StdRng) {
36 let operations = env::var("OPERATIONS")
37 .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
38 .unwrap_or(10);
39
40 let reference_string_len = rng.gen_range(0..3);
41 let mut reference_string = RandomCharIter::new(&mut rng)
42 .take(reference_string_len)
43 .collect::<String>();
44 let mut buffer = Buffer::new(0, 0, History::new(reference_string.clone().into()));
45 buffer.history.group_interval = Duration::from_millis(rng.gen_range(0..=200));
46 let mut buffer_versions = Vec::new();
47 log::info!(
48 "buffer text {:?}, version: {:?}",
49 buffer.text(),
50 buffer.version()
51 );
52
53 for _i in 0..operations {
54 let (old_ranges, new_text, _) = buffer.randomly_edit(&mut rng, 5);
55 for old_range in old_ranges.iter().rev() {
56 reference_string.replace_range(old_range.clone(), &new_text);
57 }
58 assert_eq!(buffer.text(), reference_string);
59 log::info!(
60 "buffer text {:?}, version: {:?}",
61 buffer.text(),
62 buffer.version()
63 );
64
65 if rng.gen_bool(0.25) {
66 buffer.randomly_undo_redo(&mut rng);
67 reference_string = buffer.text();
68 log::info!(
69 "buffer text {:?}, version: {:?}",
70 buffer.text(),
71 buffer.version()
72 );
73 }
74
75 let range = buffer.random_byte_range(0, &mut rng);
76 assert_eq!(
77 buffer.text_summary_for_range::<TextSummary, _>(range.clone()),
78 TextSummary::from(&reference_string[range])
79 );
80
81 buffer.check_invariants();
82
83 if rng.gen_bool(0.3) {
84 buffer_versions.push((buffer.clone(), buffer.subscribe()));
85 }
86 }
87
88 for (old_buffer, subscription) in buffer_versions {
89 let edits = buffer
90 .edits_since::<usize>(&old_buffer.version)
91 .collect::<Vec<_>>();
92
93 log::info!(
94 "applying edits since version {:?} to old text: {:?}: {:?}",
95 old_buffer.version(),
96 old_buffer.text(),
97 edits,
98 );
99
100 let mut text = old_buffer.visible_text.clone();
101 for edit in edits {
102 let new_text: String = buffer.text_for_range(edit.new.clone()).collect();
103 text.replace(edit.new.start..edit.new.start + edit.old.len(), &new_text);
104 }
105 assert_eq!(text.to_string(), buffer.text());
106
107 for _ in 0..5 {
108 let end_ix = old_buffer.clip_offset(rng.gen_range(0..=old_buffer.len()), Bias::Right);
109 let start_ix = old_buffer.clip_offset(rng.gen_range(0..=end_ix), Bias::Left);
110 let range = old_buffer.anchor_before(start_ix)..old_buffer.anchor_after(end_ix);
111 let mut old_text = old_buffer.text_for_range(range.clone()).collect::<String>();
112 let edits = buffer
113 .edits_since_in_range::<usize>(&old_buffer.version, range.clone())
114 .collect::<Vec<_>>();
115 log::info!(
116 "applying edits since version {:?} to old text in range {:?}: {:?}: {:?}",
117 old_buffer.version(),
118 start_ix..end_ix,
119 old_text,
120 edits,
121 );
122
123 let new_text = buffer.text_for_range(range).collect::<String>();
124 for edit in edits {
125 old_text.replace_range(
126 edit.new.start..edit.new.start + edit.old_len(),
127 &new_text[edit.new],
128 );
129 }
130 assert_eq!(old_text, new_text);
131 }
132
133 let subscription_edits = subscription.consume();
134 log::info!(
135 "applying subscription edits since version {:?} to old text: {:?}: {:?}",
136 old_buffer.version(),
137 old_buffer.text(),
138 subscription_edits,
139 );
140
141 let mut text = old_buffer.visible_text.clone();
142 for edit in subscription_edits.into_inner() {
143 let new_text: String = buffer.text_for_range(edit.new.clone()).collect();
144 text.replace(edit.new.start..edit.new.start + edit.old.len(), &new_text);
145 }
146 assert_eq!(text.to_string(), buffer.text());
147 }
148}
149
150#[test]
151fn test_line_len() {
152 let mut buffer = Buffer::new(0, 0, History::new("".into()));
153 buffer.edit(vec![0..0], "abcd\nefg\nhij");
154 buffer.edit(vec![12..12], "kl\nmno");
155 buffer.edit(vec![18..18], "\npqrs\n");
156 buffer.edit(vec![18..21], "\nPQ");
157
158 assert_eq!(buffer.line_len(0), 4);
159 assert_eq!(buffer.line_len(1), 3);
160 assert_eq!(buffer.line_len(2), 5);
161 assert_eq!(buffer.line_len(3), 3);
162 assert_eq!(buffer.line_len(4), 4);
163 assert_eq!(buffer.line_len(5), 0);
164}
165
166#[test]
167fn test_text_summary_for_range() {
168 let buffer = Buffer::new(0, 0, History::new("ab\nefg\nhklm\nnopqrs\ntuvwxyz".into()));
169 assert_eq!(
170 buffer.text_summary_for_range::<TextSummary, _>(1..3),
171 TextSummary {
172 bytes: 2,
173 lines: Point::new(1, 0),
174 lines_utf16: PointUtf16::new(1, 0),
175 first_line_chars: 1,
176 last_line_chars: 0,
177 longest_row: 0,
178 longest_row_chars: 1,
179 }
180 );
181 assert_eq!(
182 buffer.text_summary_for_range::<TextSummary, _>(1..12),
183 TextSummary {
184 bytes: 11,
185 lines: Point::new(3, 0),
186 lines_utf16: PointUtf16::new(3, 0),
187 first_line_chars: 1,
188 last_line_chars: 0,
189 longest_row: 2,
190 longest_row_chars: 4,
191 }
192 );
193 assert_eq!(
194 buffer.text_summary_for_range::<TextSummary, _>(0..20),
195 TextSummary {
196 bytes: 20,
197 lines: Point::new(4, 1),
198 lines_utf16: PointUtf16::new(4, 1),
199 first_line_chars: 2,
200 last_line_chars: 1,
201 longest_row: 3,
202 longest_row_chars: 6,
203 }
204 );
205 assert_eq!(
206 buffer.text_summary_for_range::<TextSummary, _>(0..22),
207 TextSummary {
208 bytes: 22,
209 lines: Point::new(4, 3),
210 lines_utf16: PointUtf16::new(4, 3),
211 first_line_chars: 2,
212 last_line_chars: 3,
213 longest_row: 3,
214 longest_row_chars: 6,
215 }
216 );
217 assert_eq!(
218 buffer.text_summary_for_range::<TextSummary, _>(7..22),
219 TextSummary {
220 bytes: 15,
221 lines: Point::new(2, 3),
222 lines_utf16: PointUtf16::new(2, 3),
223 first_line_chars: 4,
224 last_line_chars: 3,
225 longest_row: 1,
226 longest_row_chars: 6,
227 }
228 );
229}
230
231#[test]
232fn test_chars_at() {
233 let mut buffer = Buffer::new(0, 0, History::new("".into()));
234 buffer.edit(vec![0..0], "abcd\nefgh\nij");
235 buffer.edit(vec![12..12], "kl\nmno");
236 buffer.edit(vec![18..18], "\npqrs");
237 buffer.edit(vec![18..21], "\nPQ");
238
239 let chars = buffer.chars_at(Point::new(0, 0));
240 assert_eq!(chars.collect::<String>(), "abcd\nefgh\nijkl\nmno\nPQrs");
241
242 let chars = buffer.chars_at(Point::new(1, 0));
243 assert_eq!(chars.collect::<String>(), "efgh\nijkl\nmno\nPQrs");
244
245 let chars = buffer.chars_at(Point::new(2, 0));
246 assert_eq!(chars.collect::<String>(), "ijkl\nmno\nPQrs");
247
248 let chars = buffer.chars_at(Point::new(3, 0));
249 assert_eq!(chars.collect::<String>(), "mno\nPQrs");
250
251 let chars = buffer.chars_at(Point::new(4, 0));
252 assert_eq!(chars.collect::<String>(), "PQrs");
253
254 // Regression test:
255 let mut buffer = Buffer::new(0, 0, History::new("".into()));
256 buffer.edit(vec![0..0], "[workspace]\nmembers = [\n \"xray_core\",\n \"xray_server\",\n \"xray_cli\",\n \"xray_wasm\",\n]\n");
257 buffer.edit(vec![60..60], "\n");
258
259 let chars = buffer.chars_at(Point::new(6, 0));
260 assert_eq!(chars.collect::<String>(), " \"xray_wasm\",\n]\n");
261}
262
263#[test]
264fn test_anchors() {
265 let mut buffer = Buffer::new(0, 0, History::new("".into()));
266 buffer.edit(vec![0..0], "abc");
267 let left_anchor = buffer.anchor_before(2);
268 let right_anchor = buffer.anchor_after(2);
269
270 buffer.edit(vec![1..1], "def\n");
271 assert_eq!(buffer.text(), "adef\nbc");
272 assert_eq!(left_anchor.to_offset(&buffer), 6);
273 assert_eq!(right_anchor.to_offset(&buffer), 6);
274 assert_eq!(left_anchor.to_point(&buffer), Point { row: 1, column: 1 });
275 assert_eq!(right_anchor.to_point(&buffer), Point { row: 1, column: 1 });
276
277 buffer.edit(vec![2..3], "");
278 assert_eq!(buffer.text(), "adf\nbc");
279 assert_eq!(left_anchor.to_offset(&buffer), 5);
280 assert_eq!(right_anchor.to_offset(&buffer), 5);
281 assert_eq!(left_anchor.to_point(&buffer), Point { row: 1, column: 1 });
282 assert_eq!(right_anchor.to_point(&buffer), Point { row: 1, column: 1 });
283
284 buffer.edit(vec![5..5], "ghi\n");
285 assert_eq!(buffer.text(), "adf\nbghi\nc");
286 assert_eq!(left_anchor.to_offset(&buffer), 5);
287 assert_eq!(right_anchor.to_offset(&buffer), 9);
288 assert_eq!(left_anchor.to_point(&buffer), Point { row: 1, column: 1 });
289 assert_eq!(right_anchor.to_point(&buffer), Point { row: 2, column: 0 });
290
291 buffer.edit(vec![7..9], "");
292 assert_eq!(buffer.text(), "adf\nbghc");
293 assert_eq!(left_anchor.to_offset(&buffer), 5);
294 assert_eq!(right_anchor.to_offset(&buffer), 7);
295 assert_eq!(left_anchor.to_point(&buffer), Point { row: 1, column: 1 },);
296 assert_eq!(right_anchor.to_point(&buffer), Point { row: 1, column: 3 });
297
298 // Ensure anchoring to a point is equivalent to anchoring to an offset.
299 assert_eq!(
300 buffer.anchor_before(Point { row: 0, column: 0 }),
301 buffer.anchor_before(0)
302 );
303 assert_eq!(
304 buffer.anchor_before(Point { row: 0, column: 1 }),
305 buffer.anchor_before(1)
306 );
307 assert_eq!(
308 buffer.anchor_before(Point { row: 0, column: 2 }),
309 buffer.anchor_before(2)
310 );
311 assert_eq!(
312 buffer.anchor_before(Point { row: 0, column: 3 }),
313 buffer.anchor_before(3)
314 );
315 assert_eq!(
316 buffer.anchor_before(Point { row: 1, column: 0 }),
317 buffer.anchor_before(4)
318 );
319 assert_eq!(
320 buffer.anchor_before(Point { row: 1, column: 1 }),
321 buffer.anchor_before(5)
322 );
323 assert_eq!(
324 buffer.anchor_before(Point { row: 1, column: 2 }),
325 buffer.anchor_before(6)
326 );
327 assert_eq!(
328 buffer.anchor_before(Point { row: 1, column: 3 }),
329 buffer.anchor_before(7)
330 );
331 assert_eq!(
332 buffer.anchor_before(Point { row: 1, column: 4 }),
333 buffer.anchor_before(8)
334 );
335
336 // Comparison between anchors.
337 let anchor_at_offset_0 = buffer.anchor_before(0);
338 let anchor_at_offset_1 = buffer.anchor_before(1);
339 let anchor_at_offset_2 = buffer.anchor_before(2);
340
341 assert_eq!(
342 anchor_at_offset_0
343 .cmp(&anchor_at_offset_0, &buffer)
344 .unwrap(),
345 Ordering::Equal
346 );
347 assert_eq!(
348 anchor_at_offset_1
349 .cmp(&anchor_at_offset_1, &buffer)
350 .unwrap(),
351 Ordering::Equal
352 );
353 assert_eq!(
354 anchor_at_offset_2
355 .cmp(&anchor_at_offset_2, &buffer)
356 .unwrap(),
357 Ordering::Equal
358 );
359
360 assert_eq!(
361 anchor_at_offset_0
362 .cmp(&anchor_at_offset_1, &buffer)
363 .unwrap(),
364 Ordering::Less
365 );
366 assert_eq!(
367 anchor_at_offset_1
368 .cmp(&anchor_at_offset_2, &buffer)
369 .unwrap(),
370 Ordering::Less
371 );
372 assert_eq!(
373 anchor_at_offset_0
374 .cmp(&anchor_at_offset_2, &buffer)
375 .unwrap(),
376 Ordering::Less
377 );
378
379 assert_eq!(
380 anchor_at_offset_1
381 .cmp(&anchor_at_offset_0, &buffer)
382 .unwrap(),
383 Ordering::Greater
384 );
385 assert_eq!(
386 anchor_at_offset_2
387 .cmp(&anchor_at_offset_1, &buffer)
388 .unwrap(),
389 Ordering::Greater
390 );
391 assert_eq!(
392 anchor_at_offset_2
393 .cmp(&anchor_at_offset_0, &buffer)
394 .unwrap(),
395 Ordering::Greater
396 );
397}
398
399#[test]
400fn test_anchors_at_start_and_end() {
401 let mut buffer = Buffer::new(0, 0, History::new("".into()));
402 let before_start_anchor = buffer.anchor_before(0);
403 let after_end_anchor = buffer.anchor_after(0);
404
405 buffer.edit(vec![0..0], "abc");
406 assert_eq!(buffer.text(), "abc");
407 assert_eq!(before_start_anchor.to_offset(&buffer), 0);
408 assert_eq!(after_end_anchor.to_offset(&buffer), 3);
409
410 let after_start_anchor = buffer.anchor_after(0);
411 let before_end_anchor = buffer.anchor_before(3);
412
413 buffer.edit(vec![3..3], "def");
414 buffer.edit(vec![0..0], "ghi");
415 assert_eq!(buffer.text(), "ghiabcdef");
416 assert_eq!(before_start_anchor.to_offset(&buffer), 0);
417 assert_eq!(after_start_anchor.to_offset(&buffer), 3);
418 assert_eq!(before_end_anchor.to_offset(&buffer), 6);
419 assert_eq!(after_end_anchor.to_offset(&buffer), 9);
420}
421
422#[test]
423fn test_undo_redo() {
424 let mut buffer = Buffer::new(0, 0, History::new("1234".into()));
425 // Set group interval to zero so as to not group edits in the undo stack.
426 buffer.history.group_interval = Duration::from_secs(0);
427
428 buffer.edit(vec![1..1], "abx");
429 buffer.edit(vec![3..4], "yzef");
430 buffer.edit(vec![3..5], "cd");
431 assert_eq!(buffer.text(), "1abcdef234");
432
433 let transactions = buffer.history.undo_stack.clone();
434 assert_eq!(transactions.len(), 3);
435
436 buffer.undo_or_redo(transactions[0].clone()).unwrap();
437 assert_eq!(buffer.text(), "1cdef234");
438 buffer.undo_or_redo(transactions[0].clone()).unwrap();
439 assert_eq!(buffer.text(), "1abcdef234");
440
441 buffer.undo_or_redo(transactions[1].clone()).unwrap();
442 assert_eq!(buffer.text(), "1abcdx234");
443 buffer.undo_or_redo(transactions[2].clone()).unwrap();
444 assert_eq!(buffer.text(), "1abx234");
445 buffer.undo_or_redo(transactions[1].clone()).unwrap();
446 assert_eq!(buffer.text(), "1abyzef234");
447 buffer.undo_or_redo(transactions[2].clone()).unwrap();
448 assert_eq!(buffer.text(), "1abcdef234");
449
450 buffer.undo_or_redo(transactions[2].clone()).unwrap();
451 assert_eq!(buffer.text(), "1abyzef234");
452 buffer.undo_or_redo(transactions[0].clone()).unwrap();
453 assert_eq!(buffer.text(), "1yzef234");
454 buffer.undo_or_redo(transactions[1].clone()).unwrap();
455 assert_eq!(buffer.text(), "1234");
456}
457
458#[test]
459fn test_history() {
460 let mut now = Instant::now();
461 let mut buffer = Buffer::new(0, 0, History::new("123456".into()));
462
463 buffer.start_transaction_at(now);
464 buffer.edit(vec![2..4], "cd");
465 buffer.end_transaction_at(now);
466 assert_eq!(buffer.text(), "12cd56");
467
468 buffer.start_transaction_at(now);
469 buffer.edit(vec![4..5], "e");
470 buffer.end_transaction_at(now).unwrap();
471 assert_eq!(buffer.text(), "12cde6");
472
473 now += buffer.history.group_interval + Duration::from_millis(1);
474 buffer.start_transaction_at(now);
475 buffer.edit(vec![0..1], "a");
476 buffer.edit(vec![1..1], "b");
477 buffer.end_transaction_at(now).unwrap();
478 assert_eq!(buffer.text(), "ab2cde6");
479
480 // Last transaction happened past the group interval, undo it on its own.
481 buffer.undo();
482 assert_eq!(buffer.text(), "12cde6");
483
484 // First two transactions happened within the group interval, undo them together.
485 buffer.undo();
486 assert_eq!(buffer.text(), "123456");
487
488 // Redo the first two transactions together.
489 buffer.redo();
490 assert_eq!(buffer.text(), "12cde6");
491
492 // Redo the last transaction on its own.
493 buffer.redo();
494 assert_eq!(buffer.text(), "ab2cde6");
495
496 buffer.start_transaction_at(now);
497 assert!(buffer.end_transaction_at(now).is_none());
498 buffer.undo();
499 assert_eq!(buffer.text(), "12cde6");
500}
501
502#[test]
503fn test_concurrent_edits() {
504 let text = "abcdef";
505
506 let mut buffer1 = Buffer::new(1, 0, History::new(text.into()));
507 let mut buffer2 = Buffer::new(2, 0, History::new(text.into()));
508 let mut buffer3 = Buffer::new(3, 0, History::new(text.into()));
509
510 let buf1_op = buffer1.edit(vec![1..2], "12");
511 assert_eq!(buffer1.text(), "a12cdef");
512 let buf2_op = buffer2.edit(vec![3..4], "34");
513 assert_eq!(buffer2.text(), "abc34ef");
514 let buf3_op = buffer3.edit(vec![5..6], "56");
515 assert_eq!(buffer3.text(), "abcde56");
516
517 buffer1.apply_op(Operation::Edit(buf2_op.clone())).unwrap();
518 buffer1.apply_op(Operation::Edit(buf3_op.clone())).unwrap();
519 buffer2.apply_op(Operation::Edit(buf1_op.clone())).unwrap();
520 buffer2.apply_op(Operation::Edit(buf3_op.clone())).unwrap();
521 buffer3.apply_op(Operation::Edit(buf1_op.clone())).unwrap();
522 buffer3.apply_op(Operation::Edit(buf2_op.clone())).unwrap();
523
524 assert_eq!(buffer1.text(), "a12c34e56");
525 assert_eq!(buffer2.text(), "a12c34e56");
526 assert_eq!(buffer3.text(), "a12c34e56");
527}
528
529#[gpui::test(iterations = 100)]
530fn test_random_concurrent_edits(mut rng: StdRng) {
531 let peers = env::var("PEERS")
532 .map(|i| i.parse().expect("invalid `PEERS` variable"))
533 .unwrap_or(5);
534 let operations = env::var("OPERATIONS")
535 .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
536 .unwrap_or(10);
537
538 let base_text_len = rng.gen_range(0..10);
539 let base_text = RandomCharIter::new(&mut rng)
540 .take(base_text_len)
541 .collect::<String>();
542 let mut replica_ids = Vec::new();
543 let mut buffers = Vec::new();
544 let mut network = Network::new(rng.clone());
545
546 for i in 0..peers {
547 let mut buffer = Buffer::new(i as ReplicaId, 0, History::new(base_text.clone().into()));
548 buffer.history.group_interval = Duration::from_millis(rng.gen_range(0..=200));
549 buffers.push(buffer);
550 replica_ids.push(i as u16);
551 network.add_peer(i as u16);
552 }
553
554 log::info!("initial text: {:?}", base_text);
555
556 let mut mutation_count = operations;
557 loop {
558 let replica_index = rng.gen_range(0..peers);
559 let replica_id = replica_ids[replica_index];
560 let buffer = &mut buffers[replica_index];
561 match rng.gen_range(0..=100) {
562 0..=50 if mutation_count != 0 => {
563 let op = buffer.randomly_edit(&mut rng, 5).2;
564 network.broadcast(buffer.replica_id, vec![op]);
565 log::info!("buffer {} text: {:?}", buffer.replica_id, buffer.text());
566 mutation_count -= 1;
567 }
568 51..=70 if mutation_count != 0 => {
569 let ops = buffer.randomly_undo_redo(&mut rng);
570 network.broadcast(buffer.replica_id, ops);
571 mutation_count -= 1;
572 }
573 71..=100 if network.has_unreceived(replica_id) => {
574 let ops = network.receive(replica_id);
575 if !ops.is_empty() {
576 log::info!(
577 "peer {} applying {} ops from the network.",
578 replica_id,
579 ops.len()
580 );
581 buffer.apply_ops(ops).unwrap();
582 }
583 }
584 _ => {}
585 }
586 buffer.check_invariants();
587
588 if mutation_count == 0 && network.is_idle() {
589 break;
590 }
591 }
592
593 let first_buffer = &buffers[0];
594 for buffer in &buffers[1..] {
595 assert_eq!(
596 buffer.text(),
597 first_buffer.text(),
598 "Replica {} text != Replica 0 text",
599 buffer.replica_id
600 );
601 buffer.check_invariants();
602 }
603}
604
605#[derive(Clone)]
606struct Envelope<T: Clone> {
607 message: T,
608 sender: ReplicaId,
609}
610
611struct Network<T: Clone, R: rand::Rng> {
612 inboxes: std::collections::BTreeMap<ReplicaId, Vec<Envelope<T>>>,
613 all_messages: Vec<T>,
614 rng: R,
615}
616
617impl Buffer {
618 fn check_invariants(&self) {
619 // Ensure every fragment is ordered by locator in the fragment tree and corresponds
620 // to an insertion fragment in the insertions tree.
621 let mut prev_fragment_id = Locator::min();
622 for fragment in self.snapshot.fragments.items(&None) {
623 assert!(fragment.id > prev_fragment_id);
624 prev_fragment_id = fragment.id.clone();
625
626 let insertion_fragment = self
627 .snapshot
628 .insertions
629 .get(
630 &InsertionFragmentKey {
631 timestamp: fragment.insertion_timestamp.local(),
632 split_offset: fragment.insertion_offset,
633 },
634 &(),
635 )
636 .unwrap();
637 assert_eq!(insertion_fragment.fragment_id, fragment.id);
638 }
639
640 let mut cursor = self.snapshot.fragments.cursor::<Option<&Locator>>();
641 for insertion_fragment in self.snapshot.insertions.cursor::<()>() {
642 cursor.seek(&Some(&insertion_fragment.fragment_id), Bias::Left, &None);
643 let fragment = cursor.item().unwrap();
644 assert_eq!(insertion_fragment.fragment_id, fragment.id);
645 assert_eq!(insertion_fragment.split_offset, fragment.insertion_offset);
646 }
647 }
648}
649
650impl<T: Clone, R: rand::Rng> Network<T, R> {
651 fn new(rng: R) -> Self {
652 Network {
653 inboxes: Default::default(),
654 all_messages: Vec::new(),
655 rng,
656 }
657 }
658
659 fn add_peer(&mut self, id: ReplicaId) {
660 self.inboxes.insert(id, Vec::new());
661 }
662
663 fn is_idle(&self) -> bool {
664 self.inboxes.values().all(|i| i.is_empty())
665 }
666
667 fn broadcast(&mut self, sender: ReplicaId, messages: Vec<T>) {
668 for (replica, inbox) in self.inboxes.iter_mut() {
669 if *replica != sender {
670 for message in &messages {
671 let min_index = inbox
672 .iter()
673 .enumerate()
674 .rev()
675 .find_map(|(index, envelope)| {
676 if sender == envelope.sender {
677 Some(index + 1)
678 } else {
679 None
680 }
681 })
682 .unwrap_or(0);
683
684 // Insert one or more duplicates of this message *after* the previous
685 // message delivered by this replica.
686 for _ in 0..self.rng.gen_range(1..4) {
687 let insertion_index = self.rng.gen_range(min_index..inbox.len() + 1);
688 inbox.insert(
689 insertion_index,
690 Envelope {
691 message: message.clone(),
692 sender,
693 },
694 );
695 }
696 }
697 }
698 }
699 self.all_messages.extend(messages);
700 }
701
702 fn has_unreceived(&self, receiver: ReplicaId) -> bool {
703 !self.inboxes[&receiver].is_empty()
704 }
705
706 fn receive(&mut self, receiver: ReplicaId) -> Vec<T> {
707 let inbox = self.inboxes.get_mut(&receiver).unwrap();
708 let count = self.rng.gen_range(0..inbox.len() + 1);
709 inbox
710 .drain(0..count)
711 .map(|envelope| envelope.message)
712 .collect()
713 }
714}