Return header instead of block from vm.apply_txn

Makefile

@@ -23,7 +23,7 @@ clean-pyc:
 	find . -name '*~' -exec rm -f {} +
 
 lint:
-	tox -eflake8py3{5,6}
+	tox -elint-py36
 
 test:
 	py.test --tb native tests

evm/chains/base.py

@@ -23,7 +23,6 @@
     MAX_UNCLE_DEPTH,
 )
 from evm.db.chain import AsyncChainDB
-from evm.db.trie import make_trie_root_and_nodes
 from evm.estimators import (
     get_gas_estimator,
 )
@@ -487,20 +486,18 @@ def apply_transaction(self, transaction):
         heavy and incurs significant perferomance overhead.
         """
         vm = self.get_vm()
-        block, receipt, computation = vm.apply_transaction(transaction)
-        receipts = block.get_receipts(self.chaindb) + [receipt]
+        base_block = vm.block
 
-        tx_root_hash, tx_kv_nodes = make_trie_root_and_nodes(block.transactions)
-        receipt_root_hash, receipt_kv_nodes = make_trie_root_and_nodes(receipts)
-        self.chaindb.persist_trie_data_dict(tx_kv_nodes)
-        self.chaindb.persist_trie_data_dict(receipt_kv_nodes)
+        new_header, receipt, computation = vm.apply_transaction(transaction)
 
-        self.header = block.header.copy(
-            transaction_root=tx_root_hash,
-            receipt_root=receipt_root_hash,
-        )
+        transactions = base_block.transactions + (transaction, )
+        receipts = base_block.get_receipts(self.chaindb) + (receipt, )
+
+        new_block = vm.set_block_transactions(base_block, new_header, transactions, receipts)
+
+        self.header = new_block.header
 
-        return block.copy(header=self.header), receipt, computation
+        return new_block, receipt, computation
 
     def estimate_gas(self, transaction, at_header=None):
         if at_header is None:

evm/db/chain.py

@@ -409,7 +409,7 @@ def get_block_uncles(self, uncles_hash: bytes) -> List[BlockHeader]:
     #
     # Transaction and Receipt API
     #
-    @to_list
+    @to_tuple
     def get_receipts(self, header: BlockHeader, receipt_class: Type[Receipt]) -> Iterable[Receipt]:
         receipt_db = HexaryTrie(db=self.db, root_hash=header.receipt_root)
         for receipt_idx in itertools.count():

evm/vm/base.py

@@ -143,12 +143,8 @@ def apply_transaction(self, transaction):
             gas_used=receipt.gas_used,
             state_root=state_root,
         )
-        self.block = self.block.copy(
-            header=new_header,
-            transactions=tuple(self.block.transactions) + (transaction,),
-        )
 
-        return self.block, receipt, computation
+        return new_header, receipt, computation
 
     #
     # Mining
@@ -181,25 +177,37 @@ def import_block(self, block):
             in block.transactions
         ]
         if execution_data:
-            _, receipts, _ = zip(*execution_data)
+            headers, receipts, _ = zip(*execution_data)
+            header_with_txns = headers[-1]
         else:
             receipts = tuple()
+            header_with_txns = self.block.header
 
-        tx_root_hash, tx_kv_nodes = make_trie_root_and_nodes(block.transactions)
-        receipt_root_hash, receipt_kv_nodes = make_trie_root_and_nodes(receipts)
+        self.block = self.set_block_transactions(
+            self.block,
+            header_with_txns,
+            block.transactions,
+            receipts,
+        )
+
+        return self.mine_block()
 
+    def set_block_transactions(self, base_block, new_header, transactions, receipts):
+
+        tx_root_hash, tx_kv_nodes = make_trie_root_and_nodes(transactions)
         self.chaindb.persist_trie_data_dict(tx_kv_nodes)
+
+        receipt_root_hash, receipt_kv_nodes = make_trie_root_and_nodes(receipts)
         self.chaindb.persist_trie_data_dict(receipt_kv_nodes)
 
-        self.block = self.block.copy(
-            header=self.block.header.copy(
+        return base_block.copy(
+            transactions=transactions,
+            header=new_header.copy(
                 transaction_root=tx_root_hash,
                 receipt_root=receipt_root_hash,
             ),
         )
 
-        return self.mine_block()
-
     def mine_block(self, *args, **kwargs):
         """
         Mine the current block. Proxies to self.pack_block method.

tests/core/chain-object/test_chain.py

@@ -55,11 +55,10 @@ def test_import_block_validation(valid_chain, funded_address, funded_address_ini
 
 
 def test_import_block(chain, tx):
-    vm = chain.get_vm()
-    *_, computation = vm.apply_transaction(tx)
+    new_block, _, computation = chain.apply_transaction(tx)
     assert computation.is_success
 
-    block = chain.import_block(vm.block)
+    block = chain.import_block(new_block)
     assert block.transactions == (tx,)
     assert chain.get_block_by_hash(block.hash) == block
     assert chain.get_canonical_block_by_number(block.number) == block

tests/core/vm/test_vm.py

@@ -20,22 +20,20 @@ def test_apply_transaction(
         funded_address_private_key,
         funded_address_initial_balance):
     vm = chain.get_vm()
-    tx_idx = len(vm.block.transactions)
     recipient = decode_hex('0xa94f5374fce5edbc8e2a8697c15331677e6ebf0c')
     amount = 100
     from_ = funded_address
     tx = new_transaction(vm, from_, recipient, amount, funded_address_private_key)
-    *_, computation = vm.apply_transaction(tx)
+    new_header, _, computation = vm.apply_transaction(tx)
 
     assert not computation.is_error
     tx_gas = tx.gas_price * constants.GAS_TX
     account_db = vm.state.account_db
     assert account_db.get_balance(from_) == (
         funded_address_initial_balance - amount - tx_gas)
     assert account_db.get_balance(recipient) == amount
-    block = vm.block
-    assert block.transactions[tx_idx] == tx
-    assert block.header.gas_used == constants.GAS_TX
+
+    assert new_header.gas_used == constants.GAS_TX
 
 
 def test_mine_block_issues_block_reward(chain):
@@ -46,14 +44,13 @@ def test_mine_block_issues_block_reward(chain):
 
 
 def test_import_block(chain, funded_address, funded_address_private_key):
-    vm = chain.get_vm()
     recipient = decode_hex('0xa94f5374fce5edbc8e2a8697c15331677e6ebf0c')
     amount = 100
     from_ = funded_address
-    tx = new_transaction(vm, from_, recipient, amount, funded_address_private_key)
-    *_, computation = vm.apply_transaction(tx)
+    tx = new_transaction(chain.get_vm(), from_, recipient, amount, funded_address_private_key)
+    new_block, _, computation = chain.apply_transaction(tx)
 
     assert not computation.is_error
-    parent_vm = chain.get_chain_at_block_parent(vm.block).get_vm()
-    block = parent_vm.import_block(vm.block)
+    parent_vm = chain.get_chain_at_block_parent(new_block).get_vm()
+    block = parent_vm.import_block(new_block)
     assert block.transactions == (tx,)

tests/json-fixtures/test_state.py

@@ -307,7 +307,10 @@ def test_state_fixtures(fixture, fixture_vm_class):
         )
 
     try:
-        block, _, computation = vm.apply_transaction(transaction)
+        header, receipt, computation = vm.apply_transaction(transaction)
+        transactions = vm.block.transactions + (transaction, )
+        receipts = vm.block.get_receipts(chaindb) + (receipt, )
+        block = vm.set_block_transactions(vm.block, header, transactions, receipts)
     except ValidationError as err:
         block = vm.block
         transaction_error = err

tox.ini

@@ -63,8 +63,9 @@ basepython=python3.6
 setenv=MYPYPATH={toxinidir}:{toxinidir}/stubs
 commands=
     flake8 {toxinidir}/eth_typing
+    flake8 {toxinidir}/evm
     flake8 {toxinidir}/p2p
     flake8 {toxinidir}/trinity
-    flake8 {toxinidir}/tests/trinity --exclude=""
+    flake8 {toxinidir}/tests
     # TODO: Drop --ignore-missing-imports once we have type annotations for eth_utils, coincurve and cytoolz
     mypy --follow-imports=silent --ignore-missing-imports --check-untyped-defs --disallow-incomplete-defs -p eth_typing -p p2p -p trinity