miden-crypto/src/merkle/mmr/tests.rs
src/merkle/mmr/tests.rsRaw
1use super::{
2 super::{InnerNodeInfo, Rpo256, RpoDigest},
3 bit::TrueBitPositionIterator,
4 full::high_bitmask,
5 leaf_to_corresponding_tree, nodes_in_forest, Mmr, MmrPeaks, PartialMmr,
6};
7use crate::{
8 merkle::{int_to_node, InOrderIndex, MerklePath, MerkleTree, MmrProof, NodeIndex},
9 Felt, Word,
10};
11use alloc::vec::Vec;
12
13#[test]
14fn test_position_equal_or_higher_than_leafs_is_never_contained() {
15 let empty_forest = 0;
16 for pos in 1..1024 {
17 // pos is index, 0 based
18 // tree is a length counter, 1 based
19 // so a valid pos is always smaller, not equal, to tree
20 assert_eq!(leaf_to_corresponding_tree(pos, pos), None);
21 assert_eq!(leaf_to_corresponding_tree(pos, pos - 1), None);
22 // and empty forest has no trees, so no position is valid
23 assert_eq!(leaf_to_corresponding_tree(pos, empty_forest), None);
24 }
25}
26
27#[test]
28fn test_position_zero_is_always_contained_by_the_highest_tree() {
29 for leaves in 1..1024usize {
30 let tree = leaves.ilog2();
31 assert_eq!(leaf_to_corresponding_tree(0, leaves), Some(tree));
32 }
33}
34
35#[test]
36fn test_leaf_to_corresponding_tree() {
37 assert_eq!(leaf_to_corresponding_tree(0, 0b0001), Some(0));
38 assert_eq!(leaf_to_corresponding_tree(0, 0b0010), Some(1));
39 assert_eq!(leaf_to_corresponding_tree(0, 0b0011), Some(1));
40 assert_eq!(leaf_to_corresponding_tree(0, 0b1011), Some(3));
41
42 // position one is always owned by the left-most tree
43 assert_eq!(leaf_to_corresponding_tree(1, 0b0010), Some(1));
44 assert_eq!(leaf_to_corresponding_tree(1, 0b0011), Some(1));
45 assert_eq!(leaf_to_corresponding_tree(1, 0b1011), Some(3));
46
47 // position two starts as its own root, and then it is merged with the left-most tree
48 assert_eq!(leaf_to_corresponding_tree(2, 0b0011), Some(0));
49 assert_eq!(leaf_to_corresponding_tree(2, 0b0100), Some(2));
50 assert_eq!(leaf_to_corresponding_tree(2, 0b1011), Some(3));
51
52 // position tree is merged on the left-most tree
53 assert_eq!(leaf_to_corresponding_tree(3, 0b0011), None);
54 assert_eq!(leaf_to_corresponding_tree(3, 0b0100), Some(2));
55 assert_eq!(leaf_to_corresponding_tree(3, 0b1011), Some(3));
56
57 assert_eq!(leaf_to_corresponding_tree(4, 0b0101), Some(0));
58 assert_eq!(leaf_to_corresponding_tree(4, 0b0110), Some(1));
59 assert_eq!(leaf_to_corresponding_tree(4, 0b0111), Some(1));
60 assert_eq!(leaf_to_corresponding_tree(4, 0b1000), Some(3));
61
62 assert_eq!(leaf_to_corresponding_tree(12, 0b01101), Some(0));
63 assert_eq!(leaf_to_corresponding_tree(12, 0b01110), Some(1));
64 assert_eq!(leaf_to_corresponding_tree(12, 0b01111), Some(1));
65 assert_eq!(leaf_to_corresponding_tree(12, 0b10000), Some(4));
66}
67
68#[test]
69fn test_high_bitmask() {
70 assert_eq!(high_bitmask(0), usize::MAX);
71 assert_eq!(high_bitmask(1), usize::MAX << 1);
72 assert_eq!(high_bitmask(usize::BITS - 2), 0b11usize.rotate_right(2));
73 assert_eq!(high_bitmask(usize::BITS - 1), 0b1usize.rotate_right(1));
74 assert_eq!(high_bitmask(usize::BITS), 0, "overflow should be handled");
75}
76
77#[test]
78fn test_nodes_in_forest() {
79 assert_eq!(nodes_in_forest(0b0000), 0);
80 assert_eq!(nodes_in_forest(0b0001), 1);
81 assert_eq!(nodes_in_forest(0b0010), 3);
82 assert_eq!(nodes_in_forest(0b0011), 4);
83 assert_eq!(nodes_in_forest(0b0100), 7);
84 assert_eq!(nodes_in_forest(0b0101), 8);
85 assert_eq!(nodes_in_forest(0b0110), 10);
86 assert_eq!(nodes_in_forest(0b0111), 11);
87 assert_eq!(nodes_in_forest(0b1000), 15);
88 assert_eq!(nodes_in_forest(0b1001), 16);
89 assert_eq!(nodes_in_forest(0b1010), 18);
90 assert_eq!(nodes_in_forest(0b1011), 19);
91}
92
93#[test]
94fn test_nodes_in_forest_single_bit() {
95 assert_eq!(nodes_in_forest(2usize.pow(0)), 2usize.pow(1) - 1);
96 assert_eq!(nodes_in_forest(2usize.pow(1)), 2usize.pow(2) - 1);
97 assert_eq!(nodes_in_forest(2usize.pow(2)), 2usize.pow(3) - 1);
98 assert_eq!(nodes_in_forest(2usize.pow(3)), 2usize.pow(4) - 1);
99
100 for bit in 0..(usize::BITS - 1) {
101 let size = 2usize.pow(bit + 1) - 1;
102 assert_eq!(nodes_in_forest(1usize << bit), size);
103 }
104}
105
106const LEAVES: [RpoDigest; 7] = [
107 int_to_node(0),
108 int_to_node(1),
109 int_to_node(2),
110 int_to_node(3),
111 int_to_node(4),
112 int_to_node(5),
113 int_to_node(6),
114];
115
116#[test]
117fn test_mmr_simple() {
118 let mut postorder = vec![
119 LEAVES[0],
120 LEAVES[1],
121 merge(LEAVES[0], LEAVES[1]),
122 LEAVES[2],
123 LEAVES[3],
124 merge(LEAVES[2], LEAVES[3]),
125 ];
126 postorder.push(merge(postorder[2], postorder[5]));
127 postorder.push(LEAVES[4]);
128 postorder.push(LEAVES[5]);
129 postorder.push(merge(LEAVES[4], LEAVES[5]));
130 postorder.push(LEAVES[6]);
131
132 let mut mmr = Mmr::new();
133 assert_eq!(mmr.forest(), 0);
134 assert_eq!(mmr.nodes.len(), 0);
135
136 mmr.add(LEAVES[0]);
137 assert_eq!(mmr.forest(), 1);
138 assert_eq!(mmr.nodes.len(), 1);
139 assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
140
141 let acc = mmr.peaks();
142 assert_eq!(acc.num_leaves(), 1);
143 assert_eq!(acc.peaks(), &[postorder[0]]);
144
145 mmr.add(LEAVES[1]);
146 assert_eq!(mmr.forest(), 2);
147 assert_eq!(mmr.nodes.len(), 3);
148 assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
149
150 let acc = mmr.peaks();
151 assert_eq!(acc.num_leaves(), 2);
152 assert_eq!(acc.peaks(), &[postorder[2]]);
153
154 mmr.add(LEAVES[2]);
155 assert_eq!(mmr.forest(), 3);
156 assert_eq!(mmr.nodes.len(), 4);
157 assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
158
159 let acc = mmr.peaks();
160 assert_eq!(acc.num_leaves(), 3);
161 assert_eq!(acc.peaks(), &[postorder[2], postorder[3]]);
162
163 mmr.add(LEAVES[3]);
164 assert_eq!(mmr.forest(), 4);
165 assert_eq!(mmr.nodes.len(), 7);
166 assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
167
168 let acc = mmr.peaks();
169 assert_eq!(acc.num_leaves(), 4);
170 assert_eq!(acc.peaks(), &[postorder[6]]);
171
172 mmr.add(LEAVES[4]);
173 assert_eq!(mmr.forest(), 5);
174 assert_eq!(mmr.nodes.len(), 8);
175 assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
176
177 let acc = mmr.peaks();
178 assert_eq!(acc.num_leaves(), 5);
179 assert_eq!(acc.peaks(), &[postorder[6], postorder[7]]);
180
181 mmr.add(LEAVES[5]);
182 assert_eq!(mmr.forest(), 6);
183 assert_eq!(mmr.nodes.len(), 10);
184 assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
185
186 let acc = mmr.peaks();
187 assert_eq!(acc.num_leaves(), 6);
188 assert_eq!(acc.peaks(), &[postorder[6], postorder[9]]);
189
190 mmr.add(LEAVES[6]);
191 assert_eq!(mmr.forest(), 7);
192 assert_eq!(mmr.nodes.len(), 11);
193 assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
194
195 let acc = mmr.peaks();
196 assert_eq!(acc.num_leaves(), 7);
197 assert_eq!(acc.peaks(), &[postorder[6], postorder[9], postorder[10]]);
198}
199
200#[test]
201fn test_mmr_open() {
202 let mmr: Mmr = LEAVES.into();
203 let h01 = merge(LEAVES[0], LEAVES[1]);
204 let h23 = merge(LEAVES[2], LEAVES[3]);
205
206 // node at pos 7 is the root
207 assert!(mmr.open(7).is_err(), "Element 7 is not in the tree, result should be None");
208
209 // node at pos 6 is the root
210 let empty: MerklePath = MerklePath::new(vec![]);
211 let opening = mmr
212 .open(6)
213 .expect("Element 6 is contained in the tree, expected an opening result.");
214 assert_eq!(opening.merkle_path, empty);
215 assert_eq!(opening.forest, mmr.forest);
216 assert_eq!(opening.position, 6);
217 assert!(
218 mmr.peaks().verify(LEAVES[6], opening),
219 "MmrProof should be valid for the current accumulator."
220 );
221
222 // nodes 4,5 are depth 1
223 let root_to_path = MerklePath::new(vec![LEAVES[4]]);
224 let opening = mmr
225 .open(5)
226 .expect("Element 5 is contained in the tree, expected an opening result.");
227 assert_eq!(opening.merkle_path, root_to_path);
228 assert_eq!(opening.forest, mmr.forest);
229 assert_eq!(opening.position, 5);
230 assert!(
231 mmr.peaks().verify(LEAVES[5], opening),
232 "MmrProof should be valid for the current accumulator."
233 );
234
235 let root_to_path = MerklePath::new(vec![LEAVES[5]]);
236 let opening = mmr
237 .open(4)
238 .expect("Element 4 is contained in the tree, expected an opening result.");
239 assert_eq!(opening.merkle_path, root_to_path);
240 assert_eq!(opening.forest, mmr.forest);
241 assert_eq!(opening.position, 4);
242 assert!(
243 mmr.peaks().verify(LEAVES[4], opening),
244 "MmrProof should be valid for the current accumulator."
245 );
246
247 // nodes 0,1,2,3 are detph 2
248 let root_to_path = MerklePath::new(vec![LEAVES[2], h01]);
249 let opening = mmr
250 .open(3)
251 .expect("Element 3 is contained in the tree, expected an opening result.");
252 assert_eq!(opening.merkle_path, root_to_path);
253 assert_eq!(opening.forest, mmr.forest);
254 assert_eq!(opening.position, 3);
255 assert!(
256 mmr.peaks().verify(LEAVES[3], opening),
257 "MmrProof should be valid for the current accumulator."
258 );
259
260 let root_to_path = MerklePath::new(vec![LEAVES[3], h01]);
261 let opening = mmr
262 .open(2)
263 .expect("Element 2 is contained in the tree, expected an opening result.");
264 assert_eq!(opening.merkle_path, root_to_path);
265 assert_eq!(opening.forest, mmr.forest);
266 assert_eq!(opening.position, 2);
267 assert!(
268 mmr.peaks().verify(LEAVES[2], opening),
269 "MmrProof should be valid for the current accumulator."
270 );
271
272 let root_to_path = MerklePath::new(vec![LEAVES[0], h23]);
273 let opening = mmr
274 .open(1)
275 .expect("Element 1 is contained in the tree, expected an opening result.");
276 assert_eq!(opening.merkle_path, root_to_path);
277 assert_eq!(opening.forest, mmr.forest);
278 assert_eq!(opening.position, 1);
279 assert!(
280 mmr.peaks().verify(LEAVES[1], opening),
281 "MmrProof should be valid for the current accumulator."
282 );
283
284 let root_to_path = MerklePath::new(vec![LEAVES[1], h23]);
285 let opening = mmr
286 .open(0)
287 .expect("Element 0 is contained in the tree, expected an opening result.");
288 assert_eq!(opening.merkle_path, root_to_path);
289 assert_eq!(opening.forest, mmr.forest);
290 assert_eq!(opening.position, 0);
291 assert!(
292 mmr.peaks().verify(LEAVES[0], opening),
293 "MmrProof should be valid for the current accumulator."
294 );
295}
296
297#[test]
298fn test_mmr_open_older_version() {
299 let mmr: Mmr = LEAVES.into();
300
301 fn is_even(v: &usize) -> bool {
302 v & 1 == 0
303 }
304
305 // merkle path of a node is empty if there are no elements to pair with it
306 for pos in (0..mmr.forest()).filter(is_even) {
307 let forest = pos + 1;
308 let proof = mmr.open_at(pos, forest).unwrap();
309 assert_eq!(proof.forest, forest);
310 assert_eq!(proof.merkle_path.nodes(), []);
311 assert_eq!(proof.position, pos);
312 }
313
314 // openings match that of a merkle tree
315 let mtree: MerkleTree = LEAVES[..4].try_into().unwrap();
316 for forest in 4..=LEAVES.len() {
317 for pos in 0..4 {
318 let idx = NodeIndex::new(2, pos).unwrap();
319 let path = mtree.get_path(idx).unwrap();
320 let proof = mmr.open_at(pos as usize, forest).unwrap();
321 assert_eq!(path, proof.merkle_path);
322 }
323 }
324 let mtree: MerkleTree = LEAVES[4..6].try_into().unwrap();
325 for forest in 6..=LEAVES.len() {
326 for pos in 0..2 {
327 let idx = NodeIndex::new(1, pos).unwrap();
328 let path = mtree.get_path(idx).unwrap();
329 // account for the bigger tree with 4 elements
330 let mmr_pos = (pos + 4) as usize;
331 let proof = mmr.open_at(mmr_pos, forest).unwrap();
332 assert_eq!(path, proof.merkle_path);
333 }
334 }
335}
336
337/// Tests the openings of a simple Mmr with a single tree of depth 8.
338#[test]
339fn test_mmr_open_eight() {
340 let leaves = [
341 int_to_node(0),
342 int_to_node(1),
343 int_to_node(2),
344 int_to_node(3),
345 int_to_node(4),
346 int_to_node(5),
347 int_to_node(6),
348 int_to_node(7),
349 ];
350
351 let mtree: MerkleTree = leaves.as_slice().try_into().unwrap();
352 let forest = leaves.len();
353 let mmr: Mmr = leaves.into();
354 let root = mtree.root();
355
356 let position = 0;
357 let proof = mmr.open(position).unwrap();
358 let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
359 assert_eq!(proof, MmrProof { forest, position, merkle_path });
360 assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
361
362 let position = 1;
363 let proof = mmr.open(position).unwrap();
364 let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
365 assert_eq!(proof, MmrProof { forest, position, merkle_path });
366 assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
367
368 let position = 2;
369 let proof = mmr.open(position).unwrap();
370 let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
371 assert_eq!(proof, MmrProof { forest, position, merkle_path });
372 assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
373
374 let position = 3;
375 let proof = mmr.open(position).unwrap();
376 let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
377 assert_eq!(proof, MmrProof { forest, position, merkle_path });
378 assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
379
380 let position = 4;
381 let proof = mmr.open(position).unwrap();
382 let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
383 assert_eq!(proof, MmrProof { forest, position, merkle_path });
384 assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
385
386 let position = 5;
387 let proof = mmr.open(position).unwrap();
388 let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
389 assert_eq!(proof, MmrProof { forest, position, merkle_path });
390 assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
391
392 let position = 6;
393 let proof = mmr.open(position).unwrap();
394 let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
395 assert_eq!(proof, MmrProof { forest, position, merkle_path });
396 assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
397
398 let position = 7;
399 let proof = mmr.open(position).unwrap();
400 let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
401 assert_eq!(proof, MmrProof { forest, position, merkle_path });
402 assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
403}
404
405/// Tests the openings of Mmr with a 3 trees of depths 4, 2, and 1.
406#[test]
407fn test_mmr_open_seven() {
408 let mtree1: MerkleTree = LEAVES[..4].try_into().unwrap();
409 let mtree2: MerkleTree = LEAVES[4..6].try_into().unwrap();
410
411 let forest = LEAVES.len();
412 let mmr: Mmr = LEAVES.into();
413
414 let position = 0;
415 let proof = mmr.open(position).unwrap();
416 let merkle_path: MerklePath =
417 mtree1.get_path(NodeIndex::new(2, position as u64).unwrap()).unwrap();
418 assert_eq!(proof, MmrProof { forest, position, merkle_path });
419 assert_eq!(proof.merkle_path.compute_root(0, LEAVES[0]).unwrap(), mtree1.root());
420
421 let position = 1;
422 let proof = mmr.open(position).unwrap();
423 let merkle_path: MerklePath =
424 mtree1.get_path(NodeIndex::new(2, position as u64).unwrap()).unwrap();
425 assert_eq!(proof, MmrProof { forest, position, merkle_path });
426 assert_eq!(proof.merkle_path.compute_root(1, LEAVES[1]).unwrap(), mtree1.root());
427
428 let position = 2;
429 let proof = mmr.open(position).unwrap();
430 let merkle_path: MerklePath =
431 mtree1.get_path(NodeIndex::new(2, position as u64).unwrap()).unwrap();
432 assert_eq!(proof, MmrProof { forest, position, merkle_path });
433 assert_eq!(proof.merkle_path.compute_root(2, LEAVES[2]).unwrap(), mtree1.root());
434
435 let position = 3;
436 let proof = mmr.open(position).unwrap();
437 let merkle_path: MerklePath =
438 mtree1.get_path(NodeIndex::new(2, position as u64).unwrap()).unwrap();
439 assert_eq!(proof, MmrProof { forest, position, merkle_path });
440 assert_eq!(proof.merkle_path.compute_root(3, LEAVES[3]).unwrap(), mtree1.root());
441
442 let position = 4;
443 let proof = mmr.open(position).unwrap();
444 let merkle_path: MerklePath = mtree2.get_path(NodeIndex::new(1, 0u64).unwrap()).unwrap();
445 assert_eq!(proof, MmrProof { forest, position, merkle_path });
446 assert_eq!(proof.merkle_path.compute_root(0, LEAVES[4]).unwrap(), mtree2.root());
447
448 let position = 5;
449 let proof = mmr.open(position).unwrap();
450 let merkle_path: MerklePath = mtree2.get_path(NodeIndex::new(1, 1u64).unwrap()).unwrap();
451 assert_eq!(proof, MmrProof { forest, position, merkle_path });
452 assert_eq!(proof.merkle_path.compute_root(1, LEAVES[5]).unwrap(), mtree2.root());
453
454 let position = 6;
455 let proof = mmr.open(position).unwrap();
456 let merkle_path: MerklePath = [].as_ref().into();
457 assert_eq!(proof, MmrProof { forest, position, merkle_path });
458 assert_eq!(proof.merkle_path.compute_root(0, LEAVES[6]).unwrap(), LEAVES[6]);
459}
460
461#[test]
462fn test_mmr_get() {
463 let mmr: Mmr = LEAVES.into();
464 assert_eq!(mmr.get(0).unwrap(), LEAVES[0], "value at pos 0 must correspond");
465 assert_eq!(mmr.get(1).unwrap(), LEAVES[1], "value at pos 1 must correspond");
466 assert_eq!(mmr.get(2).unwrap(), LEAVES[2], "value at pos 2 must correspond");
467 assert_eq!(mmr.get(3).unwrap(), LEAVES[3], "value at pos 3 must correspond");
468 assert_eq!(mmr.get(4).unwrap(), LEAVES[4], "value at pos 4 must correspond");
469 assert_eq!(mmr.get(5).unwrap(), LEAVES[5], "value at pos 5 must correspond");
470 assert_eq!(mmr.get(6).unwrap(), LEAVES[6], "value at pos 6 must correspond");
471 assert!(mmr.get(7).is_err());
472}
473
474#[test]
475fn test_mmr_invariants() {
476 let mut mmr = Mmr::new();
477 for v in 1..=1028 {
478 mmr.add(int_to_node(v));
479 let accumulator = mmr.peaks();
480 assert_eq!(v as usize, mmr.forest(), "MMR leaf count must increase by one on every add");
481 assert_eq!(
482 v as usize,
483 accumulator.num_leaves(),
484 "MMR and its accumulator must match leaves count"
485 );
486 assert_eq!(
487 accumulator.num_leaves().count_ones() as usize,
488 accumulator.peaks().len(),
489 "bits on leaves must match the number of peaks"
490 );
491
492 let expected_nodes: usize = TrueBitPositionIterator::new(mmr.forest())
493 .map(|bit_pos| nodes_in_forest(1 << bit_pos))
494 .sum();
495
496 assert_eq!(
497 expected_nodes,
498 mmr.nodes.len(),
499 "the sum of every tree size must be equal to the number of nodes in the MMR (forest: {:b})",
500 mmr.forest(),
501 );
502 }
503}
504
505#[test]
506fn test_bit_position_iterator() {
507 assert_eq!(TrueBitPositionIterator::new(0).count(), 0);
508 assert_eq!(TrueBitPositionIterator::new(0).rev().count(), 0);
509
510 assert_eq!(TrueBitPositionIterator::new(1).collect::<Vec<u32>>(), vec![0]);
511 assert_eq!(TrueBitPositionIterator::new(1).rev().collect::<Vec<u32>>(), vec![0],);
512
513 assert_eq!(TrueBitPositionIterator::new(2).collect::<Vec<u32>>(), vec![1]);
514 assert_eq!(TrueBitPositionIterator::new(2).rev().collect::<Vec<u32>>(), vec![1],);
515
516 assert_eq!(TrueBitPositionIterator::new(3).collect::<Vec<u32>>(), vec![0, 1],);
517 assert_eq!(TrueBitPositionIterator::new(3).rev().collect::<Vec<u32>>(), vec![1, 0],);
518
519 assert_eq!(
520 TrueBitPositionIterator::new(0b11010101).collect::<Vec<u32>>(),
521 vec![0, 2, 4, 6, 7],
522 );
523 assert_eq!(
524 TrueBitPositionIterator::new(0b11010101).rev().collect::<Vec<u32>>(),
525 vec![7, 6, 4, 2, 0],
526 );
527}
528
529#[test]
530fn test_mmr_inner_nodes() {
531 let mmr: Mmr = LEAVES.into();
532 let nodes: Vec<InnerNodeInfo> = mmr.inner_nodes().collect();
533
534 let h01 = Rpo256::merge(&[LEAVES[0], LEAVES[1]]);
535 let h23 = Rpo256::merge(&[LEAVES[2], LEAVES[3]]);
536 let h0123 = Rpo256::merge(&[h01, h23]);
537 let h45 = Rpo256::merge(&[LEAVES[4], LEAVES[5]]);
538 let postorder = vec![
539 InnerNodeInfo {
540 value: h01,
541 left: LEAVES[0],
542 right: LEAVES[1],
543 },
544 InnerNodeInfo {
545 value: h23,
546 left: LEAVES[2],
547 right: LEAVES[3],
548 },
549 InnerNodeInfo { value: h0123, left: h01, right: h23 },
550 InnerNodeInfo {
551 value: h45,
552 left: LEAVES[4],
553 right: LEAVES[5],
554 },
555 ];
556
557 assert_eq!(postorder, nodes);
558}
559
560#[test]
561fn test_mmr_peaks() {
562 let mmr: Mmr = LEAVES.into();
563
564 let forest = 0b0001;
565 let acc = mmr.peaks_at(forest).unwrap();
566 assert_eq!(acc.num_leaves(), forest);
567 assert_eq!(acc.peaks(), &[mmr.nodes[0]]);
568
569 let forest = 0b0010;
570 let acc = mmr.peaks_at(forest).unwrap();
571 assert_eq!(acc.num_leaves(), forest);
572 assert_eq!(acc.peaks(), &[mmr.nodes[2]]);
573
574 let forest = 0b0011;
575 let acc = mmr.peaks_at(forest).unwrap();
576 assert_eq!(acc.num_leaves(), forest);
577 assert_eq!(acc.peaks(), &[mmr.nodes[2], mmr.nodes[3]]);
578
579 let forest = 0b0100;
580 let acc = mmr.peaks_at(forest).unwrap();
581 assert_eq!(acc.num_leaves(), forest);
582 assert_eq!(acc.peaks(), &[mmr.nodes[6]]);
583
584 let forest = 0b0101;
585 let acc = mmr.peaks_at(forest).unwrap();
586 assert_eq!(acc.num_leaves(), forest);
587 assert_eq!(acc.peaks(), &[mmr.nodes[6], mmr.nodes[7]]);
588
589 let forest = 0b0110;
590 let acc = mmr.peaks_at(forest).unwrap();
591 assert_eq!(acc.num_leaves(), forest);
592 assert_eq!(acc.peaks(), &[mmr.nodes[6], mmr.nodes[9]]);
593
594 let forest = 0b0111;
595 let acc = mmr.peaks_at(forest).unwrap();
596 assert_eq!(acc.num_leaves(), forest);
597 assert_eq!(acc.peaks(), &[mmr.nodes[6], mmr.nodes[9], mmr.nodes[10]]);
598}
599
600#[test]
601fn test_mmr_hash_peaks() {
602 let mmr: Mmr = LEAVES.into();
603 let peaks = mmr.peaks();
604
605 let first_peak = Rpo256::merge(&[
606 Rpo256::merge(&[LEAVES[0], LEAVES[1]]),
607 Rpo256::merge(&[LEAVES[2], LEAVES[3]]),
608 ]);
609 let second_peak = Rpo256::merge(&[LEAVES[4], LEAVES[5]]);
610 let third_peak = LEAVES[6];
611
612 // minimum length is 16
613 let mut expected_peaks = [first_peak, second_peak, third_peak].to_vec();
614 expected_peaks.resize(16, RpoDigest::default());
615 assert_eq!(peaks.hash_peaks(), Rpo256::hash_elements(&digests_to_elements(&expected_peaks)));
616}
617
618#[test]
619fn test_mmr_peaks_hash_less_than_16() {
620 let mut peaks = Vec::new();
621
622 for i in 0..16 {
623 peaks.push(int_to_node(i));
624
625 let num_leaves = (1 << peaks.len()) - 1;
626 let accumulator = MmrPeaks::new(num_leaves, peaks.clone()).unwrap();
627
628 // minimum length is 16
629 let mut expected_peaks = peaks.clone();
630 expected_peaks.resize(16, RpoDigest::default());
631 assert_eq!(
632 accumulator.hash_peaks(),
633 Rpo256::hash_elements(&digests_to_elements(&expected_peaks))
634 );
635 }
636}
637
638#[test]
639fn test_mmr_peaks_hash_odd() {
640 let peaks: Vec<_> = (0..=17).map(int_to_node).collect();
641
642 let num_leaves = (1 << peaks.len()) - 1;
643 let accumulator = MmrPeaks::new(num_leaves, peaks.clone()).unwrap();
644
645 // odd length bigger than 16 is padded to the next even number
646 let mut expected_peaks = peaks;
647 expected_peaks.resize(18, RpoDigest::default());
648 assert_eq!(
649 accumulator.hash_peaks(),
650 Rpo256::hash_elements(&digests_to_elements(&expected_peaks))
651 );
652}
653
654#[test]
655fn test_mmr_delta() {
656 let mmr: Mmr = LEAVES.into();
657 let acc = mmr.peaks();
658
659 // original_forest can't have more elements
660 assert!(
661 mmr.get_delta(LEAVES.len() + 1, mmr.forest()).is_err(),
662 "Can not provide updates for a newer Mmr"
663 );
664
665 // if the number of elements is the same there is no change
666 assert!(
667 mmr.get_delta(LEAVES.len(), mmr.forest()).unwrap().data.is_empty(),
668 "There are no updates for the same Mmr version"
669 );
670
671 // missing the last element added, which is itself a tree peak
672 assert_eq!(mmr.get_delta(6, mmr.forest()).unwrap().data, vec![acc.peaks()[2]], "one peak");
673
674 // missing the sibling to complete the tree of depth 2, and the last element
675 assert_eq!(
676 mmr.get_delta(5, mmr.forest()).unwrap().data,
677 vec![LEAVES[5], acc.peaks()[2]],
678 "one sibling, one peak"
679 );
680
681 // missing the whole last two trees, only send the peaks
682 assert_eq!(
683 mmr.get_delta(4, mmr.forest()).unwrap().data,
684 vec![acc.peaks()[1], acc.peaks()[2]],
685 "two peaks"
686 );
687
688 // missing the sibling to complete the first tree, and the two last trees
689 assert_eq!(
690 mmr.get_delta(3, mmr.forest()).unwrap().data,
691 vec![LEAVES[3], acc.peaks()[1], acc.peaks()[2]],
692 "one sibling, two peaks"
693 );
694
695 // missing half of the first tree, only send the computed element (not the leaves), and the new
696 // peaks
697 assert_eq!(
698 mmr.get_delta(2, mmr.forest()).unwrap().data,
699 vec![mmr.nodes[5], acc.peaks()[1], acc.peaks()[2]],
700 "one sibling, two peaks"
701 );
702
703 assert_eq!(
704 mmr.get_delta(1, mmr.forest()).unwrap().data,
705 vec![LEAVES[1], mmr.nodes[5], acc.peaks()[1], acc.peaks()[2]],
706 "one sibling, two peaks"
707 );
708
709 assert_eq!(&mmr.get_delta(0, mmr.forest()).unwrap().data, acc.peaks(), "all peaks");
710}
711
712#[test]
713fn test_mmr_delta_old_forest() {
714 let mmr: Mmr = LEAVES.into();
715
716 // from_forest must be smaller-or-equal to to_forest
717 for version in 1..=mmr.forest() {
718 assert!(mmr.get_delta(version + 1, version).is_err());
719 }
720
721 // when from_forest and to_forest are equal, there are no updates
722 for version in 1..=mmr.forest() {
723 let delta = mmr.get_delta(version, version).unwrap();
724 assert!(delta.data.is_empty());
725 assert_eq!(delta.forest, version);
726 }
727
728 // test update which merges the odd peak to the right
729 for count in 0..(mmr.forest() / 2) {
730 // *2 because every iteration tests a pair
731 // +1 because the Mmr is 1-indexed
732 let from_forest = (count * 2) + 1;
733 let to_forest = (count * 2) + 2;
734 let delta = mmr.get_delta(from_forest, to_forest).unwrap();
735
736 // *2 because every iteration tests a pair
737 // +1 because sibling is the odd element
738 let sibling = (count * 2) + 1;
739 assert_eq!(delta.data, [LEAVES[sibling]]);
740 assert_eq!(delta.forest, to_forest);
741 }
742
743 let version = 4;
744 let delta = mmr.get_delta(1, version).unwrap();
745 assert_eq!(delta.data, [mmr.nodes[1], mmr.nodes[5]]);
746 assert_eq!(delta.forest, version);
747
748 let version = 5;
749 let delta = mmr.get_delta(1, version).unwrap();
750 assert_eq!(delta.data, [mmr.nodes[1], mmr.nodes[5], mmr.nodes[7]]);
751 assert_eq!(delta.forest, version);
752}
753
754#[test]
755fn test_partial_mmr_simple() {
756 let mmr: Mmr = LEAVES.into();
757 let peaks = mmr.peaks();
758 let mut partial: PartialMmr = peaks.clone().into();
759
760 // check initial state of the partial mmr
761 assert_eq!(partial.peaks(), peaks);
762 assert_eq!(partial.forest(), peaks.num_leaves());
763 assert_eq!(partial.forest(), LEAVES.len());
764 assert_eq!(partial.peaks().num_peaks(), 3);
765 assert_eq!(partial.nodes.len(), 0);
766
767 // check state after adding tracking one element
768 let proof1 = mmr.open(0).unwrap();
769 let el1 = mmr.get(proof1.position).unwrap();
770 partial.track(proof1.position, el1, &proof1.merkle_path).unwrap();
771
772 // check the number of nodes increased by the number of nodes in the proof
773 assert_eq!(partial.nodes.len(), proof1.merkle_path.len());
774 // check the values match
775 let idx = InOrderIndex::from_leaf_pos(proof1.position);
776 assert_eq!(partial.nodes[&idx.sibling()], proof1.merkle_path[0]);
777 let idx = idx.parent();
778 assert_eq!(partial.nodes[&idx.sibling()], proof1.merkle_path[1]);
779
780 let proof2 = mmr.open(1).unwrap();
781 let el2 = mmr.get(proof2.position).unwrap();
782 partial.track(proof2.position, el2, &proof2.merkle_path).unwrap();
783
784 // check the number of nodes increased by a single element (the one that is not shared)
785 assert_eq!(partial.nodes.len(), 3);
786 // check the values match
787 let idx = InOrderIndex::from_leaf_pos(proof2.position);
788 assert_eq!(partial.nodes[&idx.sibling()], proof2.merkle_path[0]);
789 let idx = idx.parent();
790 assert_eq!(partial.nodes[&idx.sibling()], proof2.merkle_path[1]);
791}
792
793#[test]
794fn test_partial_mmr_update_single() {
795 let mut full = Mmr::new();
796 let zero = int_to_node(0);
797 full.add(zero);
798 let mut partial: PartialMmr = full.peaks().into();
799
800 let proof = full.open(0).unwrap();
801 partial.track(proof.position, zero, &proof.merkle_path).unwrap();
802
803 for i in 1..100 {
804 let node = int_to_node(i);
805 full.add(node);
806 let delta = full.get_delta(partial.forest(), full.forest()).unwrap();
807 partial.apply(delta).unwrap();
808
809 assert_eq!(partial.forest(), full.forest());
810 assert_eq!(partial.peaks(), full.peaks());
811
812 let proof1 = full.open(i as usize).unwrap();
813 partial.track(proof1.position, node, &proof1.merkle_path).unwrap();
814 let proof2 = partial.open(proof1.position).unwrap().unwrap();
815 assert_eq!(proof1.merkle_path, proof2.merkle_path);
816 }
817}
818
819#[test]
820fn test_mmr_add_invalid_odd_leaf() {
821 let mmr: Mmr = LEAVES.into();
822 let acc = mmr.peaks();
823 let mut partial: PartialMmr = acc.clone().into();
824
825 let empty = MerklePath::new(Vec::new());
826
827 // None of the other leaves should work
828 for node in LEAVES.iter().cloned().rev().skip(1) {
829 let result = partial.track(LEAVES.len() - 1, node, &empty);
830 assert!(result.is_err());
831 }
832
833 let result = partial.track(LEAVES.len() - 1, LEAVES[6], &empty);
834 assert!(result.is_ok());
835}
836
837mod property_tests {
838 use proptest::prelude::*;
839
840 use super::leaf_to_corresponding_tree;
841
842 proptest! {
843 #[test]
844 fn test_last_position_is_always_contained_in_the_last_tree(leaves in any::<usize>().prop_filter("cant have an empty tree", |v| *v != 0)) {
845 let last_pos = leaves - 1;
846 let lowest_bit = leaves.trailing_zeros();
847
848 assert_eq!(
849 leaf_to_corresponding_tree(last_pos, leaves),
850 Some(lowest_bit),
851 );
852 }
853 }
854
855 proptest! {
856 #[test]
857 fn test_contained_tree_is_always_power_of_two((leaves, pos) in any::<usize>().prop_flat_map(|v| (Just(v), 0..v))) {
858 let tree_bit = leaf_to_corresponding_tree(pos, leaves).expect("pos is smaller than leaves, there should always be a corresponding tree");
859 let mask = 1usize << tree_bit;
860
861 assert!(tree_bit < usize::BITS, "the result must be a bit in usize");
862 assert!(mask & leaves != 0, "the result should be a tree in leaves");
863 }
864 }
865}
866
867// HELPER FUNCTIONS
868// ================================================================================================
869
870fn digests_to_elements(digests: &[RpoDigest]) -> Vec<Felt> {
871 digests.iter().flat_map(Word::from).collect()
872}
873
874// short hand for the rpo hash, used to make test code more concise and easy to read
875fn merge(l: RpoDigest, r: RpoDigest) -> RpoDigest {
876 Rpo256::merge(&[l, r])
877}