make_head_candidate() now returns both the block and state

Also fixes mk_genesis_data() to use the correct key names.
Closes #726

Author: gsalgado

ethereum/genesis_helpers.py

@@ -67,7 +67,7 @@ def mk_genesis_data(env, **kwargs):
 
     allowed_args = set([
         'start_alloc',
-        'prevhash',
+        'parent_hash',
         'coinbase',
         'difficulty',
         'gas_limit',
@@ -79,12 +79,12 @@ def mk_genesis_data(env, **kwargs):
     assert set(kwargs.keys()).issubset(allowed_args)
 
     genesis_data = {
-        "prevhash": kwargs.get('prevhash', encode_hex(env.config['GENESIS_PREVHASH'])),
+        "parentHash": kwargs.get('parent_hash', encode_hex(env.config['GENESIS_PREVHASH'])),
         "coinbase": kwargs.get('coinbase', encode_hex(env.config['GENESIS_COINBASE'])),
         "difficulty": kwargs.get('difficulty', env.config['GENESIS_DIFFICULTY']),
-        "gas_limit": kwargs.get('gas_limit', env.config['GENESIS_GAS_LIMIT']),
+        "gasLimit": kwargs.get('gas_limit', env.config['GENESIS_GAS_LIMIT']),
         "timestamp": kwargs.get('timestamp', 0),
-        "extra_data": kwargs.get('extra_data', encode_hex(env.config['GENESIS_EXTRA_DATA'])),
+        "extraData": kwargs.get('extra_data', encode_hex(env.config['GENESIS_EXTRA_DATA'])),
         "mixhash": kwargs.get('mixhash', encode_hex(env.config['GENESIS_MIXHASH'])),
         "nonce": kwargs.get('nonce', encode_hex(env.config['GENESIS_NONCE'])),
         "alloc": kwargs.get('start_alloc', env.config['GENESIS_INITIAL_ALLOC'])

ethereum/meta.py

@@ -66,4 +66,4 @@ def make_head_candidate(chain, txqueue=None,
     # Set state root, receipt root, etc
     set_execution_results(temp_state, blk)
     log.info('Created head candidate successfully')
-    return blk
+    return blk, temp_state

ethereum/tests/test_chain.py

@@ -54,7 +54,7 @@ def mine_on_chain(chain, parent=None, transactions=[], coinbase=None, timestamp=
     for t in transactions:
         txqueue.add_transaction(t)
     parent_timestamp = parent.timestamp if parent else chain.state.timestamp
-    hc = meta.make_head_candidate(chain, txqueue, parent,
+    hc, _ = meta.make_head_candidate(chain, txqueue, parent,
                              timestamp or parent_timestamp + 1, coinbase or '\x00'*20)
     assert hc.difficulty == 1
     m = ethpow.Miner(hc)

ethereum/tests/todo/test_pos.py

@@ -54,7 +54,7 @@
 
 # Create and sign a block
 def make_block(chain, key, randao, vchash, skips):
-    h = make_head_candidate(chain, TransactionQueue(), timestamp=get_timestamp(chain, skips))
+    h, _ = make_head_candidate(chain, TransactionQueue(), timestamp=get_timestamp(chain, skips))
     return sign_block(h, key, randao.get_parent(call_casper(chain.state, 'getRandao', [vchash])), vchash, skips)
 
 next_validator = call_casper(s, 'getValidator', [0])