def test_reset_balance_in_trie_and_revert():
db = InMemoryDb()
b = TokenBalances(b"", db)
mapping = {
token_id_encode("Q" + chr(65 + i)): int(i * 1e3) + 42
for i in range(17)
}
b._balances = mapping.copy()
b.commit()
journal = []
b.set_balance(journal, 999, 999)
assert b.balance(999) == 999
b.reset(journal)
assert b.is_blank()
assert b.to_dict() == {}
for op in journal:
op()
assert not b.is_blank()
assert b.to_dict() == mapping
def test_encoding_change_from_dict_to_trie():
db = InMemoryDb()
b = TokenBalances(b"", db)
# start with 16 entries - right below the threshold
mapping = {
token_id_encode("Q" + chr(65 + i)): int(i * 1e3) + 42
for i in range(16)
}
b._balances = mapping.copy()
b.commit()
assert b.serialize().startswith(b"\x00")
assert b.token_trie is None
# add one more entry and expect changes
journal = []
new_token = token_id_encode("QKC")
b.set_balance(journal, new_token, 123)
assert b.balance(new_token) == 123
b.commit()
assert b.token_trie is not None
assert b.serialize().startswith(b"\x01")
root1 = b.token_trie.root_hash
copied_mapping = mapping.copy()
copied_mapping[new_token] = 123
assert b.to_dict() == copied_mapping
# clear all balances except QKC
for k in mapping:
b.set_balance(journal, k, 0)
# still have those token keys in balance map
assert b.balance(token_id_encode("QA")) == 0
assert b.to_dict() == {new_token: 123}
# trie hash should change after serialization
b.commit()
serialized = b.serialize()
root2 = b.token_trie.root_hash
assert serialized == b"\x01" + root2
assert root1 != root2
# balance map truncated, entries with 0 value will be ignored
assert b._balances == {}
assert b.balance(token_id_encode("QB")) == 0
assert len(b._balances) == 0
assert b.to_dict() == {new_token: 123}
assert not b.is_blank()
# remove the last entry
b.set_balance(journal, new_token, 0)
assert b.to_dict() == {}
b.commit()
assert b.token_trie.root_hash == BLANK_ROOT
assert b._balances == {}