Update pyevm backend subclass, use URI for provider connection

nucypher/blockchain/eth/interfaces.py

@@ -1,9 +1,15 @@
 from urllib.parse import urlparse
 
 from constant_sorrow import constants
+from eth import constants as pyevm_constants
 from eth_keys.datatypes import PublicKey, Signature
+from eth_tester import EthereumTester
 from eth_utils import to_canonical_address
+<<<<<<< HEAD
 from typing import Tuple, Union
+=======
+from eth_utils import to_wei
+>>>>>>> 73225ce... Update pyevm backend subclass, use URI for provider connection
 from web3 import Web3, WebsocketProvider, HTTPProvider, IPCProvider
 from web3.contract import Contract
 from web3.providers.eth_tester.main import EthereumTesterProvider
@@ -206,10 +212,31 @@ class BlockchainInterface:
             if uri_breakdown.scheme == 'pyevm':
 
                 if uri_breakdown.netloc == 'tester':
+<<<<<<< HEAD
 
                     NUCYPHER_GAS_LIMIT = 4899698  # 4626271  # TODO: Move ME
                     genesis_parameter_overrides = {'gas_limit': NUCYPHER_GAS_LIMIT}
                     pyevm_backend = PyEVMBackend(genesis_parameter_overrides=genesis_parameter_overrides)
+=======
+                    from nucypher.blockchain.eth.utilities import OverridablePyEVMBackend
+
+                    NUCYPHER_GAS_LIMIT = 4899698  # 4626271
+
+                    GENESIS_PARAMS = {
+                        'parent_hash': pyevm_constants.GENESIS_PARENT_HASH,
+                        'uncles_hash': pyevm_constants.EMPTY_UNCLE_HASH,
+                        'coinbase': pyevm_constants.ZERO_ADDRESS,
+                        'transaction_root': pyevm_constants.BLANK_ROOT_HASH,
+                        'receipt_root': pyevm_constants.BLANK_ROOT_HASH,
+                        'difficulty': pyevm_constants.GENESIS_DIFFICULTY,
+                        'block_number': pyevm_constants.GENESIS_BLOCK_NUMBER,
+                        'gas_limit': NUCYPHER_GAS_LIMIT,
+                        'extra_data': pyevm_constants.GENESIS_EXTRA_DATA,
+                        'nonce': pyevm_constants.GENESIS_NONCE
+                    }
+
+                    pyevm_backend = OverridablePyEVMBackend(genesis_params=GENESIS_PARAMS)
+>>>>>>> 73225ce... Update pyevm backend subclass, use URI for provider connection
 
                     eth_tester = EthereumTester(backend=pyevm_backend, auto_mine_transactions=True)
                     provider = EthereumTesterProvider(ethereum_tester=eth_tester)

tests/fixtures.py

@@ -1,19 +1,20 @@
 import contextlib
-import datetime
 import os
 import tempfile
 
+import datetime
 import maya
 import pytest
 from constant_sorrow import constants
 from eth_utils import to_checksum_address
+from nucypher.blockchain.eth.utilities import TemporaryEthereumContractRegistry
 from sqlalchemy.engine import create_engine
 
 from nucypher.blockchain.eth.chains import TesterBlockchain
 from nucypher.blockchain.eth.deployers import PolicyManagerDeployer, NucypherTokenDeployer, MinerEscrowDeployer
 from nucypher.blockchain.eth.interfaces import BlockchainDeployerInterface
-from nucypher.blockchain.eth.sol.compile import SolidityCompiler
 from nucypher.blockchain.eth.registry import TemporaryEthereumContractRegistry
+from nucypher.blockchain.eth.sol.compile import SolidityCompiler
 from nucypher.characters import Alice, Bob
 from nucypher.data_sources import DataSource
 from nucypher.keystore import keystore
@@ -21,6 +22,8 @@ from nucypher.keystore.db import Base
 from nucypher.keystore.keypairs import SigningKeypair
 from nucypher.utilities.blockchain import make_ursulas, token_airdrop
 from nucypher.utilities.network import MockRestMiddleware
+
+
 #
 # Setup
 #
@@ -247,6 +250,7 @@ def testerchain(solidity_compiler):
     temp_registrar = TemporaryEthereumContractRegistry()
 
     # Use the the custom provider and registrar to init an interface
+
     circumflex = BlockchainDeployerInterface(compiler=solidity_compiler,  # freshly recompile if not None
                                              registry=temp_registrar,
                                              provider_uri='pyevm://tester')