arnaucube
arnaucube/miden-cryptoPublic Self-hosted repository
miden-crypto/src/merkle/mmr/tests.rs
src/merkle/mmr/tests.rsRaw
  1use super::{
  2    super::{InnerNodeInfo, Rpo256, RpoDigest, Vec},
  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};
 11
 12#[test]
 13fn test_position_equal_or_higher_than_leafs_is_never_contained() {
 14    let empty_forest = 0;
 15    for pos in 1..1024 {
 16        // pos is index, 0 based
 17        // tree is a length counter, 1 based
 18        // so a valid pos is always smaller, not equal, to tree
 19        assert_eq!(leaf_to_corresponding_tree(pos, pos), None);
 20        assert_eq!(leaf_to_corresponding_tree(pos, pos - 1), None);
 21        // and empty forest has no trees, so no position is valid
 22        assert_eq!(leaf_to_corresponding_tree(pos, empty_forest), None);
 23    }
 24}
 25
 26#[test]
 27fn test_position_zero_is_always_contained_by_the_highest_tree() {
 28    for leaves in 1..1024usize {
 29        let tree = leaves.ilog2();
 30        assert_eq!(leaf_to_corresponding_tree(0, leaves), Some(tree));
 31    }
 32}
 33
 34#[test]
 35fn test_leaf_to_corresponding_tree() {
 36    assert_eq!(leaf_to_corresponding_tree(0, 0b0001), Some(0));
 37    assert_eq!(leaf_to_corresponding_tree(0, 0b0010), Some(1));
 38    assert_eq!(leaf_to_corresponding_tree(0, 0b0011), Some(1));
 39    assert_eq!(leaf_to_corresponding_tree(0, 0b1011), Some(3));
 40
 41    // position one is always owned by the left-most tree
 42    assert_eq!(leaf_to_corresponding_tree(1, 0b0010), Some(1));
 43    assert_eq!(leaf_to_corresponding_tree(1, 0b0011), Some(1));
 44    assert_eq!(leaf_to_corresponding_tree(1, 0b1011), Some(3));
 45
 46    // position two starts as its own root, and then it is merged with the left-most tree
 47    assert_eq!(leaf_to_corresponding_tree(2, 0b0011), Some(0));
 48    assert_eq!(leaf_to_corresponding_tree(2, 0b0100), Some(2));
 49    assert_eq!(leaf_to_corresponding_tree(2, 0b1011), Some(3));
 50
 51    // position tree is merged on the left-most tree
 52    assert_eq!(leaf_to_corresponding_tree(3, 0b0011), None);
 53    assert_eq!(leaf_to_corresponding_tree(3, 0b0100), Some(2));
 54    assert_eq!(leaf_to_corresponding_tree(3, 0b1011), Some(3));
 55
 56    assert_eq!(leaf_to_corresponding_tree(4, 0b0101), Some(0));
 57    assert_eq!(leaf_to_corresponding_tree(4, 0b0110), Some(1));
 58    assert_eq!(leaf_to_corresponding_tree(4, 0b0111), Some(1));
 59    assert_eq!(leaf_to_corresponding_tree(4, 0b1000), Some(3));
 60
 61    assert_eq!(leaf_to_corresponding_tree(12, 0b01101), Some(0));
 62    assert_eq!(leaf_to_corresponding_tree(12, 0b01110), Some(1));
 63    assert_eq!(leaf_to_corresponding_tree(12, 0b01111), Some(1));
 64    assert_eq!(leaf_to_corresponding_tree(12, 0b10000), Some(4));
 65}
 66
 67#[test]
 68fn test_high_bitmask() {
 69    assert_eq!(high_bitmask(0), usize::MAX);
 70    assert_eq!(high_bitmask(1), usize::MAX << 1);
 71    assert_eq!(high_bitmask(usize::BITS - 2), 0b11usize.rotate_right(2));
 72    assert_eq!(high_bitmask(usize::BITS - 1), 0b1usize.rotate_right(1));
 73    assert_eq!(high_bitmask(usize::BITS), 0, "overflow should be handled");
 74}
 75
 76#[test]
 77fn test_nodes_in_forest() {
 78    assert_eq!(nodes_in_forest(0b0000), 0);
 79    assert_eq!(nodes_in_forest(0b0001), 1);
 80    assert_eq!(nodes_in_forest(0b0010), 3);
 81    assert_eq!(nodes_in_forest(0b0011), 4);
 82    assert_eq!(nodes_in_forest(0b0100), 7);
 83    assert_eq!(nodes_in_forest(0b0101), 8);
 84    assert_eq!(nodes_in_forest(0b0110), 10);
 85    assert_eq!(nodes_in_forest(0b0111), 11);
 86    assert_eq!(nodes_in_forest(0b1000), 15);
 87    assert_eq!(nodes_in_forest(0b1001), 16);
 88    assert_eq!(nodes_in_forest(0b1010), 18);
 89    assert_eq!(nodes_in_forest(0b1011), 19);
 90}
 91
 92#[test]
 93fn test_nodes_in_forest_single_bit() {
 94    assert_eq!(nodes_in_forest(2usize.pow(0)), 2usize.pow(1) - 1);
 95    assert_eq!(nodes_in_forest(2usize.pow(1)), 2usize.pow(2) - 1);
 96    assert_eq!(nodes_in_forest(2usize.pow(2)), 2usize.pow(3) - 1);
 97    assert_eq!(nodes_in_forest(2usize.pow(3)), 2usize.pow(4) - 1);
 98
 99    for bit in 0..(usize::BITS - 1) {
100        let size = 2usize.pow(bit + 1) - 1;
101        assert_eq!(nodes_in_forest(1usize << bit), size);
102    }
103}
104
105const LEAVES: [RpoDigest; 7] = [
106    int_to_node(0),
107    int_to_node(1),
108    int_to_node(2),
109    int_to_node(3),
110    int_to_node(4),
111    int_to_node(5),
112    int_to_node(6),
113];
114
115#[test]
116fn test_mmr_simple() {
117    let mut postorder = vec![
118        LEAVES[0],
119        LEAVES[1],
120        merge(LEAVES[0], LEAVES[1]),
121        LEAVES[2],
122        LEAVES[3],
123        merge(LEAVES[2], LEAVES[3]),
124    ];
125    postorder.push(merge(postorder[2], postorder[5]));
126    postorder.push(LEAVES[4]);
127    postorder.push(LEAVES[5]);
128    postorder.push(merge(LEAVES[4], LEAVES[5]));
129    postorder.push(LEAVES[6]);
130
131    let mut mmr = Mmr::new();
132    assert_eq!(mmr.forest(), 0);
133    assert_eq!(mmr.nodes.len(), 0);
134
135    mmr.add(LEAVES[0]);
136    assert_eq!(mmr.forest(), 1);
137    assert_eq!(mmr.nodes.len(), 1);
138    assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
139
140    let acc = mmr.peaks(mmr.forest()).unwrap();
141    assert_eq!(acc.num_leaves(), 1);
142    assert_eq!(acc.peaks(), &[postorder[0]]);
143
144    mmr.add(LEAVES[1]);
145    assert_eq!(mmr.forest(), 2);
146    assert_eq!(mmr.nodes.len(), 3);
147    assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
148
149    let acc = mmr.peaks(mmr.forest()).unwrap();
150    assert_eq!(acc.num_leaves(), 2);
151    assert_eq!(acc.peaks(), &[postorder[2]]);
152
153    mmr.add(LEAVES[2]);
154    assert_eq!(mmr.forest(), 3);
155    assert_eq!(mmr.nodes.len(), 4);
156    assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
157
158    let acc = mmr.peaks(mmr.forest()).unwrap();
159    assert_eq!(acc.num_leaves(), 3);
160    assert_eq!(acc.peaks(), &[postorder[2], postorder[3]]);
161
162    mmr.add(LEAVES[3]);
163    assert_eq!(mmr.forest(), 4);
164    assert_eq!(mmr.nodes.len(), 7);
165    assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
166
167    let acc = mmr.peaks(mmr.forest()).unwrap();
168    assert_eq!(acc.num_leaves(), 4);
169    assert_eq!(acc.peaks(), &[postorder[6]]);
170
171    mmr.add(LEAVES[4]);
172    assert_eq!(mmr.forest(), 5);
173    assert_eq!(mmr.nodes.len(), 8);
174    assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
175
176    let acc = mmr.peaks(mmr.forest()).unwrap();
177    assert_eq!(acc.num_leaves(), 5);
178    assert_eq!(acc.peaks(), &[postorder[6], postorder[7]]);
179
180    mmr.add(LEAVES[5]);
181    assert_eq!(mmr.forest(), 6);
182    assert_eq!(mmr.nodes.len(), 10);
183    assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
184
185    let acc = mmr.peaks(mmr.forest()).unwrap();
186    assert_eq!(acc.num_leaves(), 6);
187    assert_eq!(acc.peaks(), &[postorder[6], postorder[9]]);
188
189    mmr.add(LEAVES[6]);
190    assert_eq!(mmr.forest(), 7);
191    assert_eq!(mmr.nodes.len(), 11);
192    assert_eq!(mmr.nodes.as_slice(), &postorder[0..mmr.nodes.len()]);
193
194    let acc = mmr.peaks(mmr.forest()).unwrap();
195    assert_eq!(acc.num_leaves(), 7);
196    assert_eq!(acc.peaks(), &[postorder[6], postorder[9], postorder[10]]);
197}
198
199#[test]
200fn test_mmr_open() {
201    let mmr: Mmr = LEAVES.into();
202    let h01 = merge(LEAVES[0], LEAVES[1]);
203    let h23 = merge(LEAVES[2], LEAVES[3]);
204
205    // node at pos 7 is the root
206    assert!(
207        mmr.open(7, mmr.forest()).is_err(),
208        "Element 7 is not in the tree, result should be None"
209    );
210
211    // node at pos 6 is the root
212    let empty: MerklePath = MerklePath::new(vec![]);
213    let opening = mmr
214        .open(6, mmr.forest())
215        .expect("Element 6 is contained in the tree, expected an opening result.");
216    assert_eq!(opening.merkle_path, empty);
217    assert_eq!(opening.forest, mmr.forest);
218    assert_eq!(opening.position, 6);
219    assert!(
220        mmr.peaks(mmr.forest()).unwrap().verify(LEAVES[6], opening),
221        "MmrProof should be valid for the current accumulator."
222    );
223
224    // nodes 4,5 are depth 1
225    let root_to_path = MerklePath::new(vec![LEAVES[4]]);
226    let opening = mmr
227        .open(5, mmr.forest())
228        .expect("Element 5 is contained in the tree, expected an opening result.");
229    assert_eq!(opening.merkle_path, root_to_path);
230    assert_eq!(opening.forest, mmr.forest);
231    assert_eq!(opening.position, 5);
232    assert!(
233        mmr.peaks(mmr.forest()).unwrap().verify(LEAVES[5], opening),
234        "MmrProof should be valid for the current accumulator."
235    );
236
237    let root_to_path = MerklePath::new(vec![LEAVES[5]]);
238    let opening = mmr
239        .open(4, mmr.forest())
240        .expect("Element 4 is contained in the tree, expected an opening result.");
241    assert_eq!(opening.merkle_path, root_to_path);
242    assert_eq!(opening.forest, mmr.forest);
243    assert_eq!(opening.position, 4);
244    assert!(
245        mmr.peaks(mmr.forest()).unwrap().verify(LEAVES[4], opening),
246        "MmrProof should be valid for the current accumulator."
247    );
248
249    // nodes 0,1,2,3 are detph 2
250    let root_to_path = MerklePath::new(vec![LEAVES[2], h01]);
251    let opening = mmr
252        .open(3, mmr.forest())
253        .expect("Element 3 is contained in the tree, expected an opening result.");
254    assert_eq!(opening.merkle_path, root_to_path);
255    assert_eq!(opening.forest, mmr.forest);
256    assert_eq!(opening.position, 3);
257    assert!(
258        mmr.peaks(mmr.forest()).unwrap().verify(LEAVES[3], opening),
259        "MmrProof should be valid for the current accumulator."
260    );
261
262    let root_to_path = MerklePath::new(vec![LEAVES[3], h01]);
263    let opening = mmr
264        .open(2, mmr.forest())
265        .expect("Element 2 is contained in the tree, expected an opening result.");
266    assert_eq!(opening.merkle_path, root_to_path);
267    assert_eq!(opening.forest, mmr.forest);
268    assert_eq!(opening.position, 2);
269    assert!(
270        mmr.peaks(mmr.forest()).unwrap().verify(LEAVES[2], opening),
271        "MmrProof should be valid for the current accumulator."
272    );
273
274    let root_to_path = MerklePath::new(vec![LEAVES[0], h23]);
275    let opening = mmr
276        .open(1, mmr.forest())
277        .expect("Element 1 is contained in the tree, expected an opening result.");
278    assert_eq!(opening.merkle_path, root_to_path);
279    assert_eq!(opening.forest, mmr.forest);
280    assert_eq!(opening.position, 1);
281    assert!(
282        mmr.peaks(mmr.forest()).unwrap().verify(LEAVES[1], opening),
283        "MmrProof should be valid for the current accumulator."
284    );
285
286    let root_to_path = MerklePath::new(vec![LEAVES[1], h23]);
287    let opening = mmr
288        .open(0, mmr.forest())
289        .expect("Element 0 is contained in the tree, expected an opening result.");
290    assert_eq!(opening.merkle_path, root_to_path);
291    assert_eq!(opening.forest, mmr.forest);
292    assert_eq!(opening.position, 0);
293    assert!(
294        mmr.peaks(mmr.forest()).unwrap().verify(LEAVES[0], opening),
295        "MmrProof should be valid for the current accumulator."
296    );
297}
298
299#[test]
300fn test_mmr_open_older_version() {
301    let mmr: Mmr = LEAVES.into();
302
303    fn is_even(v: &usize) -> bool {
304        v & 1 == 0
305    }
306
307    // merkle path of a node is empty if there are no elements to pair with it
308    for pos in (0..mmr.forest()).filter(is_even) {
309        let forest = pos + 1;
310        let proof = mmr.open(pos, forest).unwrap();
311        assert_eq!(proof.forest, forest);
312        assert_eq!(proof.merkle_path.nodes(), []);
313        assert_eq!(proof.position, pos);
314    }
315
316    // openings match that of a merkle tree
317    let mtree: MerkleTree = LEAVES[..4].try_into().unwrap();
318    for forest in 4..=LEAVES.len() {
319        for pos in 0..4 {
320            let idx = NodeIndex::new(2, pos).unwrap();
321            let path = mtree.get_path(idx).unwrap();
322            let proof = mmr.open(pos as usize, forest).unwrap();
323            assert_eq!(path, proof.merkle_path);
324        }
325    }
326    let mtree: MerkleTree = LEAVES[4..6].try_into().unwrap();
327    for forest in 6..=LEAVES.len() {
328        for pos in 0..2 {
329            let idx = NodeIndex::new(1, pos).unwrap();
330            let path = mtree.get_path(idx).unwrap();
331            // account for the bigger tree with 4 elements
332            let mmr_pos = (pos + 4) as usize;
333            let proof = mmr.open(mmr_pos, forest).unwrap();
334            assert_eq!(path, proof.merkle_path);
335        }
336    }
337}
338
339/// Tests the openings of a simple Mmr with a single tree of depth 8.
340#[test]
341fn test_mmr_open_eight() {
342    let leaves = [
343        int_to_node(0),
344        int_to_node(1),
345        int_to_node(2),
346        int_to_node(3),
347        int_to_node(4),
348        int_to_node(5),
349        int_to_node(6),
350        int_to_node(7),
351    ];
352
353    let mtree: MerkleTree = leaves.as_slice().try_into().unwrap();
354    let forest = leaves.len();
355    let mmr: Mmr = leaves.into();
356    let root = mtree.root();
357
358    let position = 0;
359    let proof = mmr.open(position, mmr.forest()).unwrap();
360    let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
361    assert_eq!(proof, MmrProof { forest, position, merkle_path });
362    assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
363
364    let position = 1;
365    let proof = mmr.open(position, mmr.forest()).unwrap();
366    let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
367    assert_eq!(proof, MmrProof { forest, position, merkle_path });
368    assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
369
370    let position = 2;
371    let proof = mmr.open(position, mmr.forest()).unwrap();
372    let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
373    assert_eq!(proof, MmrProof { forest, position, merkle_path });
374    assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
375
376    let position = 3;
377    let proof = mmr.open(position, mmr.forest()).unwrap();
378    let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
379    assert_eq!(proof, MmrProof { forest, position, merkle_path });
380    assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
381
382    let position = 4;
383    let proof = mmr.open(position, mmr.forest()).unwrap();
384    let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
385    assert_eq!(proof, MmrProof { forest, position, merkle_path });
386    assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
387
388    let position = 5;
389    let proof = mmr.open(position, mmr.forest()).unwrap();
390    let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
391    assert_eq!(proof, MmrProof { forest, position, merkle_path });
392    assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
393
394    let position = 6;
395    let proof = mmr.open(position, mmr.forest()).unwrap();
396    let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
397    assert_eq!(proof, MmrProof { forest, position, merkle_path });
398    assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
399
400    let position = 7;
401    let proof = mmr.open(position, mmr.forest()).unwrap();
402    let merkle_path = mtree.get_path(NodeIndex::new(3, position as u64).unwrap()).unwrap();
403    assert_eq!(proof, MmrProof { forest, position, merkle_path });
404    assert_eq!(proof.merkle_path.compute_root(position as u64, leaves[position]).unwrap(), root);
405}
406
407/// Tests the openings of Mmr with a 3 trees of depths 4, 2, and 1.
408#[test]
409fn test_mmr_open_seven() {
410    let mtree1: MerkleTree = LEAVES[..4].try_into().unwrap();
411    let mtree2: MerkleTree = LEAVES[4..6].try_into().unwrap();
412
413    let forest = LEAVES.len();
414    let mmr: Mmr = LEAVES.into();
415
416    let position = 0;
417    let proof = mmr.open(position, mmr.forest()).unwrap();
418    let merkle_path: MerklePath =
419        mtree1.get_path(NodeIndex::new(2, position as u64).unwrap()).unwrap();
420    assert_eq!(proof, MmrProof { forest, position, merkle_path });
421    assert_eq!(proof.merkle_path.compute_root(0, LEAVES[0]).unwrap(), mtree1.root());
422
423    let position = 1;
424    let proof = mmr.open(position, mmr.forest()).unwrap();
425    let merkle_path: MerklePath =
426        mtree1.get_path(NodeIndex::new(2, position as u64).unwrap()).unwrap();
427    assert_eq!(proof, MmrProof { forest, position, merkle_path });
428    assert_eq!(proof.merkle_path.compute_root(1, LEAVES[1]).unwrap(), mtree1.root());
429
430    let position = 2;
431    let proof = mmr.open(position, mmr.forest()).unwrap();
432    let merkle_path: MerklePath =
433        mtree1.get_path(NodeIndex::new(2, position as u64).unwrap()).unwrap();
434    assert_eq!(proof, MmrProof { forest, position, merkle_path });
435    assert_eq!(proof.merkle_path.compute_root(2, LEAVES[2]).unwrap(), mtree1.root());
436
437    let position = 3;
438    let proof = mmr.open(position, mmr.forest()).unwrap();
439    let merkle_path: MerklePath =
440        mtree1.get_path(NodeIndex::new(2, position as u64).unwrap()).unwrap();
441    assert_eq!(proof, MmrProof { forest, position, merkle_path });
442    assert_eq!(proof.merkle_path.compute_root(3, LEAVES[3]).unwrap(), mtree1.root());
443
444    let position = 4;
445    let proof = mmr.open(position, mmr.forest()).unwrap();
446    let merkle_path: MerklePath = mtree2.get_path(NodeIndex::new(1, 0u64).unwrap()).unwrap();
447    assert_eq!(proof, MmrProof { forest, position, merkle_path });
448    assert_eq!(proof.merkle_path.compute_root(0, LEAVES[4]).unwrap(), mtree2.root());
449
450    let position = 5;
451    let proof = mmr.open(position, mmr.forest()).unwrap();
452    let merkle_path: MerklePath = mtree2.get_path(NodeIndex::new(1, 1u64).unwrap()).unwrap();
453    assert_eq!(proof, MmrProof { forest, position, merkle_path });
454    assert_eq!(proof.merkle_path.compute_root(1, LEAVES[5]).unwrap(), mtree2.root());
455
456    let position = 6;
457    let proof = mmr.open(position, mmr.forest()).unwrap();
458    let merkle_path: MerklePath = [].as_ref().into();
459    assert_eq!(proof, MmrProof { forest, position, merkle_path });
460    assert_eq!(proof.merkle_path.compute_root(0, LEAVES[6]).unwrap(), LEAVES[6]);
461}
462
463#[test]
464fn test_mmr_get() {
465    let mmr: Mmr = LEAVES.into();
466    assert_eq!(mmr.get(0).unwrap(), LEAVES[0], "value at pos 0 must correspond");
467    assert_eq!(mmr.get(1).unwrap(), LEAVES[1], "value at pos 1 must correspond");
468    assert_eq!(mmr.get(2).unwrap(), LEAVES[2], "value at pos 2 must correspond");
469    assert_eq!(mmr.get(3).unwrap(), LEAVES[3], "value at pos 3 must correspond");
470    assert_eq!(mmr.get(4).unwrap(), LEAVES[4], "value at pos 4 must correspond");
471    assert_eq!(mmr.get(5).unwrap(), LEAVES[5], "value at pos 5 must correspond");
472    assert_eq!(mmr.get(6).unwrap(), LEAVES[6], "value at pos 6 must correspond");
473    assert!(mmr.get(7).is_err());
474}
475
476#[test]
477fn test_mmr_invariants() {
478    let mut mmr = Mmr::new();
479    for v in 1..=1028 {
480        mmr.add(int_to_node(v));
481        let accumulator = mmr.peaks(mmr.forest()).unwrap();
482        assert_eq!(v as usize, mmr.forest(), "MMR leaf count must increase by one on every add");
483        assert_eq!(
484            v as usize,
485            accumulator.num_leaves(),
486            "MMR and its accumulator must match leaves count"
487        );
488        assert_eq!(
489            accumulator.num_leaves().count_ones() as usize,
490            accumulator.peaks().len(),
491            "bits on leaves must match the number of peaks"
492        );
493
494        let expected_nodes: usize = TrueBitPositionIterator::new(mmr.forest())
495            .map(|bit_pos| nodes_in_forest(1 << bit_pos))
496            .sum();
497
498        assert_eq!(
499            expected_nodes,
500            mmr.nodes.len(),
501            "the sum of every tree size must be equal to the number of nodes in the MMR (forest: {:b})",
502            mmr.forest(),
503        );
504    }
505}
506
507#[test]
508fn test_bit_position_iterator() {
509    assert_eq!(TrueBitPositionIterator::new(0).count(), 0);
510    assert_eq!(TrueBitPositionIterator::new(0).rev().count(), 0);
511
512    assert_eq!(TrueBitPositionIterator::new(1).collect::<Vec<u32>>(), vec![0]);
513    assert_eq!(TrueBitPositionIterator::new(1).rev().collect::<Vec<u32>>(), vec![0],);
514
515    assert_eq!(TrueBitPositionIterator::new(2).collect::<Vec<u32>>(), vec![1]);
516    assert_eq!(TrueBitPositionIterator::new(2).rev().collect::<Vec<u32>>(), vec![1],);
517
518    assert_eq!(TrueBitPositionIterator::new(3).collect::<Vec<u32>>(), vec![0, 1],);
519    assert_eq!(TrueBitPositionIterator::new(3).rev().collect::<Vec<u32>>(), vec![1, 0],);
520
521    assert_eq!(
522        TrueBitPositionIterator::new(0b11010101).collect::<Vec<u32>>(),
523        vec![0, 2, 4, 6, 7],
524    );
525    assert_eq!(
526        TrueBitPositionIterator::new(0b11010101).rev().collect::<Vec<u32>>(),
527        vec![7, 6, 4, 2, 0],
528    );
529}
530
531#[test]
532fn test_mmr_inner_nodes() {
533    let mmr: Mmr = LEAVES.into();
534    let nodes: Vec<InnerNodeInfo> = mmr.inner_nodes().collect();
535
536    let h01 = Rpo256::merge(&[LEAVES[0], LEAVES[1]]);
537    let h23 = Rpo256::merge(&[LEAVES[2], LEAVES[3]]);
538    let h0123 = Rpo256::merge(&[h01, h23]);
539    let h45 = Rpo256::merge(&[LEAVES[4], LEAVES[5]]);
540    let postorder = vec![
541        InnerNodeInfo {
542            value: h01,
543            left: LEAVES[0],
544            right: LEAVES[1],
545        },
546        InnerNodeInfo {
547            value: h23,
548            left: LEAVES[2],
549            right: LEAVES[3],
550        },
551        InnerNodeInfo { value: h0123, left: h01, right: h23 },
552        InnerNodeInfo {
553            value: h45,
554            left: LEAVES[4],
555            right: LEAVES[5],
556        },
557    ];
558
559    assert_eq!(postorder, nodes);
560}
561
562#[test]
563fn test_mmr_peaks() {
564    let mmr: Mmr = LEAVES.into();
565
566    let forest = 0b0001;
567    let acc = mmr.peaks(forest).unwrap();
568    assert_eq!(acc.num_leaves(), forest);
569    assert_eq!(acc.peaks(), &[mmr.nodes[0]]);
570
571    let forest = 0b0010;
572    let acc = mmr.peaks(forest).unwrap();
573    assert_eq!(acc.num_leaves(), forest);
574    assert_eq!(acc.peaks(), &[mmr.nodes[2]]);
575
576    let forest = 0b0011;
577    let acc = mmr.peaks(forest).unwrap();
578    assert_eq!(acc.num_leaves(), forest);
579    assert_eq!(acc.peaks(), &[mmr.nodes[2], mmr.nodes[3]]);
580
581    let forest = 0b0100;
582    let acc = mmr.peaks(forest).unwrap();
583    assert_eq!(acc.num_leaves(), forest);
584    assert_eq!(acc.peaks(), &[mmr.nodes[6]]);
585
586    let forest = 0b0101;
587    let acc = mmr.peaks(forest).unwrap();
588    assert_eq!(acc.num_leaves(), forest);
589    assert_eq!(acc.peaks(), &[mmr.nodes[6], mmr.nodes[7]]);
590
591    let forest = 0b0110;
592    let acc = mmr.peaks(forest).unwrap();
593    assert_eq!(acc.num_leaves(), forest);
594    assert_eq!(acc.peaks(), &[mmr.nodes[6], mmr.nodes[9]]);
595
596    let forest = 0b0111;
597    let acc = mmr.peaks(forest).unwrap();
598    assert_eq!(acc.num_leaves(), forest);
599    assert_eq!(acc.peaks(), &[mmr.nodes[6], mmr.nodes[9], mmr.nodes[10]]);
600}
601
602#[test]
603fn test_mmr_hash_peaks() {
604    let mmr: Mmr = LEAVES.into();
605    let peaks = mmr.peaks(mmr.forest()).unwrap();
606
607    let first_peak = Rpo256::merge(&[
608        Rpo256::merge(&[LEAVES[0], LEAVES[1]]),
609        Rpo256::merge(&[LEAVES[2], LEAVES[3]]),
610    ]);
611    let second_peak = Rpo256::merge(&[LEAVES[4], LEAVES[5]]);
612    let third_peak = LEAVES[6];
613
614    // minimum length is 16
615    let mut expected_peaks = [first_peak, second_peak, third_peak].to_vec();
616    expected_peaks.resize(16, RpoDigest::default());
617    assert_eq!(peaks.hash_peaks(), Rpo256::hash_elements(&digests_to_elements(&expected_peaks)));
618}
619
620#[test]
621fn test_mmr_peaks_hash_less_than_16() {
622    let mut peaks = Vec::new();
623
624    for i in 0..16 {
625        peaks.push(int_to_node(i));
626
627        let num_leaves = (1 << peaks.len()) - 1;
628        let accumulator = MmrPeaks::new(num_leaves, peaks.clone()).unwrap();
629
630        // minimum length is 16
631        let mut expected_peaks = peaks.clone();
632        expected_peaks.resize(16, RpoDigest::default());
633        assert_eq!(
634            accumulator.hash_peaks(),
635            Rpo256::hash_elements(&digests_to_elements(&expected_peaks))
636        );
637    }
638}
639
640#[test]
641fn test_mmr_peaks_hash_odd() {
642    let peaks: Vec<_> = (0..=17).map(int_to_node).collect();
643
644    let num_leaves = (1 << peaks.len()) - 1;
645    let accumulator = MmrPeaks::new(num_leaves, peaks.clone()).unwrap();
646
647    // odd length bigger than 16 is padded to the next even number
648    let mut expected_peaks = peaks;
649    expected_peaks.resize(18, RpoDigest::default());
650    assert_eq!(
651        accumulator.hash_peaks(),
652        Rpo256::hash_elements(&digests_to_elements(&expected_peaks))
653    );
654}
655
656#[test]
657fn test_mmr_delta() {
658    let mmr: Mmr = LEAVES.into();
659    let acc = mmr.peaks(mmr.forest()).unwrap();
660
661    // original_forest can't have more elements
662    assert!(
663        mmr.get_delta(LEAVES.len() + 1, mmr.forest()).is_err(),
664        "Can not provide updates for a newer Mmr"
665    );
666
667    // if the number of elements is the same there is no change
668    assert!(
669        mmr.get_delta(LEAVES.len(), mmr.forest()).unwrap().data.is_empty(),
670        "There are no updates for the same Mmr version"
671    );
672
673    // missing the last element added, which is itself a tree peak
674    assert_eq!(mmr.get_delta(6, mmr.forest()).unwrap().data, vec![acc.peaks()[2]], "one peak");
675
676    // missing the sibling to complete the tree of depth 2, and the last element
677    assert_eq!(
678        mmr.get_delta(5, mmr.forest()).unwrap().data,
679        vec![LEAVES[5], acc.peaks()[2]],
680        "one sibling, one peak"
681    );
682
683    // missing the whole last two trees, only send the peaks
684    assert_eq!(
685        mmr.get_delta(4, mmr.forest()).unwrap().data,
686        vec![acc.peaks()[1], acc.peaks()[2]],
687        "two peaks"
688    );
689
690    // missing the sibling to complete the first tree, and the two last trees
691    assert_eq!(
692        mmr.get_delta(3, mmr.forest()).unwrap().data,
693        vec![LEAVES[3], acc.peaks()[1], acc.peaks()[2]],
694        "one sibling, two peaks"
695    );
696
697    // missing half of the first tree, only send the computed element (not the leaves), and the new
698    // peaks
699    assert_eq!(
700        mmr.get_delta(2, mmr.forest()).unwrap().data,
701        vec![mmr.nodes[5], acc.peaks()[1], acc.peaks()[2]],
702        "one sibling, two peaks"
703    );
704
705    assert_eq!(
706        mmr.get_delta(1, mmr.forest()).unwrap().data,
707        vec![LEAVES[1], mmr.nodes[5], acc.peaks()[1], acc.peaks()[2]],
708        "one sibling, two peaks"
709    );
710
711    assert_eq!(&mmr.get_delta(0, mmr.forest()).unwrap().data, acc.peaks(), "all peaks");
712}
713
714#[test]
715fn test_mmr_delta_old_forest() {
716    let mmr: Mmr = LEAVES.into();
717
718    // from_forest must be smaller-or-equal to to_forest
719    for version in 1..=mmr.forest() {
720        assert!(mmr.get_delta(version + 1, version).is_err());
721    }
722
723    // when from_forest and to_forest are equal, there are no updates
724    for version in 1..=mmr.forest() {
725        let delta = mmr.get_delta(version, version).unwrap();
726        assert!(delta.data.is_empty());
727        assert_eq!(delta.forest, version);
728    }
729
730    // test update which merges the odd peak to the right
731    for count in 0..(mmr.forest() / 2) {
732        // *2 because every iteration tests a pair
733        // +1 because the Mmr is 1-indexed
734        let from_forest = (count * 2) + 1;
735        let to_forest = (count * 2) + 2;
736        let delta = mmr.get_delta(from_forest, to_forest).unwrap();
737
738        // *2 because every iteration tests a pair
739        // +1 because sibling is the odd element
740        let sibling = (count * 2) + 1;
741        assert_eq!(delta.data, [LEAVES[sibling]]);
742        assert_eq!(delta.forest, to_forest);
743    }
744
745    let version = 4;
746    let delta = mmr.get_delta(1, version).unwrap();
747    assert_eq!(delta.data, [mmr.nodes[1], mmr.nodes[5]]);
748    assert_eq!(delta.forest, version);
749
750    let version = 5;
751    let delta = mmr.get_delta(1, version).unwrap();
752    assert_eq!(delta.data, [mmr.nodes[1], mmr.nodes[5], mmr.nodes[7]]);
753    assert_eq!(delta.forest, version);
754}
755
756#[test]
757fn test_partial_mmr_simple() {
758    let mmr: Mmr = LEAVES.into();
759    let peaks = mmr.peaks(mmr.forest()).unwrap();
760    let mut partial: PartialMmr = peaks.clone().into();
761
762    // check initial state of the partial mmr
763    assert_eq!(partial.peaks(), peaks);
764    assert_eq!(partial.forest(), peaks.num_leaves());
765    assert_eq!(partial.forest(), LEAVES.len());
766    assert_eq!(partial.peaks().num_peaks(), 3);
767    assert_eq!(partial.nodes.len(), 0);
768
769    // check state after adding tracking one element
770    let proof1 = mmr.open(0, mmr.forest()).unwrap();
771    let el1 = mmr.get(proof1.position).unwrap();
772    partial.add(proof1.position, el1, &proof1.merkle_path).unwrap();
773
774    // check the number of nodes increased by the number of nodes in the proof
775    assert_eq!(partial.nodes.len(), proof1.merkle_path.len());
776    // check the values match
777    let idx = InOrderIndex::from_leaf_pos(proof1.position);
778    assert_eq!(partial.nodes[&idx.sibling()], proof1.merkle_path[0]);
779    let idx = idx.parent();
780    assert_eq!(partial.nodes[&idx.sibling()], proof1.merkle_path[1]);
781
782    let proof2 = mmr.open(1, mmr.forest()).unwrap();
783    let el2 = mmr.get(proof2.position).unwrap();
784    partial.add(proof2.position, el2, &proof2.merkle_path).unwrap();
785
786    // check the number of nodes increased by a single element (the one that is not shared)
787    assert_eq!(partial.nodes.len(), 3);
788    // check the values match
789    let idx = InOrderIndex::from_leaf_pos(proof2.position);
790    assert_eq!(partial.nodes[&idx.sibling()], proof2.merkle_path[0]);
791    let idx = idx.parent();
792    assert_eq!(partial.nodes[&idx.sibling()], proof2.merkle_path[1]);
793}
794
795#[test]
796fn test_partial_mmr_update_single() {
797    let mut full = Mmr::new();
798    let zero = int_to_node(0);
799    full.add(zero);
800    let mut partial: PartialMmr = full.peaks(full.forest()).unwrap().into();
801
802    let proof = full.open(0, full.forest()).unwrap();
803    partial.add(proof.position, zero, &proof.merkle_path).unwrap();
804
805    for i in 1..100 {
806        let node = int_to_node(i);
807        full.add(node);
808        let delta = full.get_delta(partial.forest(), full.forest()).unwrap();
809        partial.apply(delta).unwrap();
810
811        assert_eq!(partial.forest(), full.forest());
812        assert_eq!(partial.peaks(), full.peaks(full.forest()).unwrap());
813
814        let proof1 = full.open(i as usize, full.forest()).unwrap();
815        partial.add(proof1.position, node, &proof1.merkle_path).unwrap();
816        let proof2 = partial.open(proof1.position).unwrap().unwrap();
817        assert_eq!(proof1.merkle_path, proof2.merkle_path);
818    }
819}
820
821#[test]
822fn test_mmr_add_invalid_odd_leaf() {
823    let mmr: Mmr = LEAVES.into();
824    let acc = mmr.peaks(mmr.forest()).unwrap();
825    let mut partial: PartialMmr = acc.clone().into();
826
827    let empty = MerklePath::new(Vec::new());
828
829    // None of the other leaves should work
830    for node in LEAVES.iter().cloned().rev().skip(1) {
831        let result = partial.add(LEAVES.len() - 1, node, &empty);
832        assert!(result.is_err());
833    }
834
835    let result = partial.add(LEAVES.len() - 1, LEAVES[6], &empty);
836    assert!(result.is_ok());
837}
838
839mod property_tests {
840    use super::leaf_to_corresponding_tree;
841    use proptest::prelude::*;
842
843    proptest! {
844        #[test]
845        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)) {
846            let last_pos = leaves - 1;
847            let lowest_bit = leaves.trailing_zeros();
848
849            assert_eq!(
850                leaf_to_corresponding_tree(last_pos, leaves),
851                Some(lowest_bit),
852            );
853        }
854    }
855
856    proptest! {
857        #[test]
858        fn test_contained_tree_is_always_power_of_two((leaves, pos) in any::<usize>().prop_flat_map(|v| (Just(v), 0..v))) {
859            let tree_bit = leaf_to_corresponding_tree(pos, leaves).expect("pos is smaller than leaves, there should always be a corresponding tree");
860            let mask = 1usize << tree_bit;
861
862            assert!(tree_bit < usize::BITS, "the result must be a bit in usize");
863            assert!(mask & leaves != 0, "the result should be a tree in leaves");
864        }
865    }
866}
867
868// HELPER FUNCTIONS
869// ================================================================================================
870
871fn digests_to_elements(digests: &[RpoDigest]) -> Vec<Felt> {
872    digests.iter().flat_map(Word::from).collect()
873}
874
875// short hand for the rpo hash, used to make test code more concise and easy to read
876fn merge(l: RpoDigest, r: RpoDigest) -> RpoDigest {
877    Rpo256::merge(&[l, r])
878}