initialize head_candidate and pep8

Author: heikoheiko

ethereum/blocks.py

@@ -100,6 +100,7 @@ def calc_difficulty(parent, timestamp):
 
 
 class Account(rlp.Serializable):
+
     """An Ethereum account.
 
     :ivar nonce: the account's nonce (the number of transactions sent by the
@@ -172,6 +173,7 @@ def bloom(self):
 
 
 class BlockHeader(rlp.Serializable):
+
     """A block header.
 
     If the block with this header exists as an instance of :class:`Block`, the
@@ -306,7 +308,7 @@ def hex_hash(self):
     @property
     def mining_hash(self):
         return utils.sha3(rlp.encode(self,
-                          BlockHeader.exclude(['mixhash', 'nonce'])))
+                                     BlockHeader.exclude(['mixhash', 'nonce'])))
 
     @property
     def seed(self):
@@ -405,6 +407,7 @@ def setter(self, value):
              set(['state_root', 'receipts_root', 'tx_list_root']),
              only_getters=False)
 class Block(rlp.Serializable):
+
     """A block.
 
     All attributes from the block header are accessible via properties
@@ -563,7 +566,7 @@ def must_le(what, a, b):
                              "database" % self)
         if (not self.is_genesis() and self.nonce and not self.header.check_pow()):
             raise ValueError("PoW check failed")
-        self.db.put('validated:'+self.hash, '1')
+        self.db.put('validated:' + self.hash, '1')
 
     @classmethod
     def init_from_header(cls, header_rlp, db):
@@ -1351,7 +1354,7 @@ def get_block(db, blockhash):
     return CachedBlock.create_cached(blk)
 
 
-#def has_block(blockhash):
+# def has_block(blockhash):
 #    return blockhash in db.DB(utils.get_db_path())
 
 

ethereum/chain.py

@@ -96,18 +96,19 @@ class Chain(object):
     :ivar head_candidate: the block which if mined by our miner would become
                           the new head
     """
+    head_candidate = None
 
     def __init__(self, db, genesis=None, new_head_cb=None, coinbase='\x00' * 20):
         self.db = self.blockchain = db
         self.new_head_cb = new_head_cb
         self.index = Index(db)
-        self.head_candidate = None
         self._coinbase = coinbase
         if genesis:
             self._initialize_blockchain(genesis)
         log.debug('chain @', head_hash=self.head)
         self.genesis = blocks.genesis(db=db)
         log.debug('got genesis', genesis_hash=self.genesis)
+        self._update_head_candidate()
 
     def _initialize_blockchain(self, genesis=None):
         log.info('Initializing new chain')