def test_merge_update_key_collision():
crdt_1, crdt_2 = CRDT(), CRDT()
crdt_1.add('a', 1)
crdt_2.add('b', 2)
crdt_1.update('a', 'b')
merged = merge(crdt_1, crdt_2)
# In this implementation of LWW the update should overwrite the original key if the key already exists
assert merged.data == {'b': 1}
def test_merge_remove_same_key_twice():
crdt_1, crdt_2 = CRDT(), CRDT()
crdt_1.add('a', 1)
crdt_2.add('a', 1)
crdt_1.remove('a')
crdt_2.remove('a')
# In a merged set, since the key is removed before, the later remove should be ignored
merged = merge(crdt_1, crdt_2)
assert len(merged.data) == 0
def test_merge_update_same_key_twice():
crdt_1, crdt_2 = CRDT(), CRDT()
crdt_1.add('a', 1)
crdt_2.add('a', 2)
crdt_1.update('a', 'b')
crdt_2.update('a', 'c')
merged = merge(crdt_1, crdt_2)
# In a LWW merge, only the latest update should be present
assert merged.data == {'c': 2}
def test_merge_add_only(ans):
crdt_1, crdt_2 = CRDT(), CRDT()
ans_1, ans_2 = slice_dict(ans, 0, len(ans) // 2), slice_dict(ans, len(ans) // 2, len(ans))
for k, v in ans_1.items():
crdt_1.add(k, v)
for k, v in ans_2.items():
crdt_2.add(k, v)
merged = merge(crdt_1, crdt_2)
assert len(merged.log) == len(crdt_1.log) + len(crdt_2.log)
assert merged.data == ans
def test_merge_add_same_key_diff_values(ans):
crdt_1, crdt_2 = CRDT(), CRDT()
ans_alt = {k:v + 1 for k, v in ans.items()}
for k, v in ans.items():
crdt_1.add(k, v)
for k, v in ans_alt.items():
crdt_2.add(k, v)
merged = merge(crdt_1, crdt_2)
assert len(merged.log) == len(crdt_1.log) + len(crdt_2.log)
# Only the values updated later should be present
assert merged.data == ans_alt
def test_merge_add_remove(ans):
crdt_1, crdt_2 = CRDT(), CRDT()
ans_1, ans_2 = slice_dict(ans, 0, len(ans) // 2), slice_dict(ans, len(ans) // 2, len(ans))
# Both CRDTs contain the same data initially
for k, v in ans.items():
crdt_1.add(k, v)
crdt_2.add(k, v)
# Remove second half of the ans set in crdt_2
for k in ans_2:
crdt_2.remove(k)
merged = merge(crdt_1, crdt_2)
# Only first half of the ans set should remain
assert merged.data == ans_1
def test_merge_add_update(ans, upd):
crdt_1, crdt_2 = CRDT(), CRDT()
ans_1, ans_2 = slice_dict(ans, 0, len(ans) // 2), slice_dict(ans, len(ans) // 2, len(ans))
for k, v in ans_1.items():
crdt_1.add(k, v)
for k, v in ans_2.items():
crdt_2.add(k, v)
for k in ans_2:
crdt_2.update(k, upd[k])
merged = merge(crdt_1, crdt_2)
# Only keys in the second half of the ans set should be updated
ans_1.update({upd[k]:v for k, v in ans_2.items()})
assert merged.data == ans_1
def test_merge_add_update_remove(ans, upd):
crdt_1, crdt_2 = CRDT(), CRDT()
ans_1, ans_2 = slice_dict(ans, 0, len(ans) // 2), slice_dict(ans, len(ans) // 2, len(ans))
for k, v in ans.items():
crdt_1.add(k, v)
crdt_2.add(k, v)
# Update the elements in the second half of the ans set in crdt_1 (opposite of test_merge_add_remove_update())
for k in ans_2:
crdt_1.update(k, upd[k])
# Remove old keys that are updated in crdt_1 in crdt_2 (opposite of test_merge_add_remove_update())
for k in ans_2:
crdt_2.remove(k)
merged = merge(crdt_1, crdt_2)
# Since this is a LWW set, the **removes** will overwrite the **updates** since they're executed later
assert merged.data == ans_1