def test_if_the_blocks_are_not_changed_then_chain_should_be_a_valid_chain(): chain = Blockchain() block_id_zero = Block() block_id_one = Block() block_id_two = Block() chain.add_block(block_id_zero) first_validation = chain.validate() assert first_validation == True chain.add_block(block_id_one) second_validation = chain.validate() assert second_validation == True chain.add_block(block_id_two) third_validation = chain.validate() assert third_validation == True
def test_if_a_block_is_changed_then_chain_should_not_be_a_valid_chain(): chain = Blockchain() block_id_zero = Block() block_id_one = Block() block_id_two = Block() chain.add_block(block_id_zero) chain.add_block(block_id_one) chain.add_block(block_id_two) block_id_one.data = {'hacked'} block_id_one.calculate_hash() validation = chain.validate() assert validation == False