def test_sealing_linked_block_sets_hashes_correctly(self):
block1 = Block()
block1.messages = self.get_messages("first", "second", "third")
block1.seal()
block2 = Block()
block2.messages = self.get_messages("fourth", "fifth")
block2.link(block1)
block2.seal()
self.assertEqual(self.block_hash(block2), block2.hash)
self.assertEqual(block2.prev_hash, block1.hash)
def test_message_tampering_invalidates_block(self):
block = Block()
block.messages = self.get_messages("first", "second", "third", "fourth", "fifth")
block.messages[1].data = "changed"
self.assertRaises(InvalidBlock, block.validate)
def test_sealing_unlinked_block_sets_hashes_correctly(self):
block = Block()
block.messages = self.get_messages("first", "second")
block.seal()
self.assertEqual(self.block_hash(block), block.hash)
