package merkle import ( . "github.com/tendermint/tendermint2/common" "bytes" "testing" ) type testItem []byte func (tI testItem) Hash() []byte { return []byte(tI) } func TestMerkleTrails(t *testing.T) { numItems := uint(100) items := make([]Hashable, numItems) for i := uint(0); i < numItems; i++ { items[i] = testItem(RandBytes(32)) } root := HashFromHashables(items) trails, rootTrail := HashTrailsFromHashables(items) // Assert that HashFromHashables and HashTrailsFromHashables are compatible. if !bytes.Equal(root, rootTrail.Hash) { t.Errorf("Root mismatch:\n%X vs\n%X", root, rootTrail.Hash) } // For each item, check the trail. for i, item := range items { itemHash := item.Hash() flatTrail := trails[i].Flatten() // Verify success ok := VerifyHashTrail(uint(i), numItems, itemHash, flatTrail, root) if !ok { t.Errorf("Verification failed for index %v.", i) } // Wrong item index should make it fail ok = VerifyHashTrail(uint(i)+1, numItems, itemHash, flatTrail, root) if ok { t.Errorf("Expected verification to fail for wrong index %v.", i) } // Trail too long should make it fail trail2 := append(flatTrail, RandBytes(32)) ok = VerifyHashTrail(uint(i), numItems, itemHash, trail2, root) if ok { t.Errorf("Expected verification to fail for wrong trail length.") } // Trail too short should make it fail trail2 = flatTrail[:len(flatTrail)-1] ok = VerifyHashTrail(uint(i), numItems, itemHash, trail2, root) if ok { t.Errorf("Expected verification to fail for wrong trail length.") } // Mutating the itemHash should make it fail. itemHash2 := make([]byte, len(itemHash)) copy(itemHash2, itemHash) itemHash2[0] += byte(0x01) ok = VerifyHashTrail(uint(i), numItems, itemHash2, flatTrail, root) if ok { t.Errorf("Expected verification to fail for mutated leaf hash") } } }