[WIP] [BLOCKED] Add Python 3.8 testing

.circleci/config.yml

@@ -6,6 +6,10 @@ version: 2.0
 common: &common
   working_directory: ~/repo
   steps:
+    # TODO: remove this step when `plyvel` gets a Python 3.8 wheel
+    - run:
+        name: install LevelDB headers dependency system-wide
+        command: sudo apt-get install libleveldb-dev
     - checkout
     - run:
         name: checkout fixtures submodule
@@ -168,6 +172,37 @@ jobs:
         environment:
           TOXENV: py37-lint
 
+  py38-core:
+    <<: *common
+    docker:
+      - image: circleci/python:3.8
+        environment:
+          TOXENV: py38-core
+  py38-database:
+    <<: *common
+    docker:
+      - image: circleci/python:3.8
+        environment:
+          TOXENV: py38-database
+  py38-transactions:
+    <<: *common
+    docker:
+      - image: circleci/python:3.8
+        environment:
+          TOXENV: py38-transactions
+  py38-vm:
+    <<: *common
+    docker:
+      - image: circleci/python:3.8
+        environment:
+          TOXENV: py38-vm
+  py38-lint:
+    <<: *common
+    docker:
+      - image: circleci/python:3.8
+        environment:
+          TOXENV: py38-lint
+
 workflows:
   version: 2
   test:
@@ -184,12 +219,17 @@ workflows:
       - py36-native-blockchain-transition
       - py36-vm
       - py37-vm
+      - py38-vm
       - py36-core
       - py37-core
+      - py38-core
       - py36-transactions
       - py37-transactions
+      - py38-transactions
       - py36-database
       - py37-database
+      - py38-database
       - py36-docs
       - py36-lint
       - py37-lint
+      - py38-lint

eth/abc.py

@@ -775,9 +775,9 @@ def __call__(self, computation: 'ComputationAPI') -> None:
     def as_opcode(cls: Type[T],
                   logic_fn: Callable[['ComputationAPI'], None],
                   mnemonic: str,
-                  gas_cost: int) -> Type[T]:
+                  gas_cost: int) -> T:
         """
-        Class factory method for turning vanilla functions into Opcode classes.
+        Class factory method for turning vanilla functions into Opcodes.
         """
         ...
 
@@ -1633,6 +1633,16 @@ def state_root(self) -> Hash32:
         """
         ...
 
+    @state_root.setter
+    def state_root(self, value: Hash32) -> None:
+        """
+        Force-set the state root hash.
+        """
+        # See: https://github.com/python/mypy/issues/4165
+        # Since we can't also decorate this with abstract method we want to be
+        # sure that the setter doesn't actually get used as a noop.
+        raise NotImplementedError
+
     @abstractmethod
     def has_root(self, state_root: bytes) -> bool:
         """
@@ -2287,7 +2297,10 @@ class VirtualMachineAPI(ConfigurableAPI):
     extra_data_max_bytes: ClassVar[int]
 
     @abstractmethod
-    def __init__(self, header: BlockHeaderAPI, chaindb: ChainDatabaseAPI) -> None:
+    def __init__(self,
+                 header: BlockHeaderAPI,
+                 chaindb: ChainDatabaseAPI,
+                 chain_context: ChainContextAPI) -> None:
         """
         Initialize the virtual machine.
         """

eth/chains/base.py

@@ -225,8 +225,8 @@ def from_genesis(cls,
             # the computed state from the initialized state database.
             raise ValidationError(
                 "The provided genesis state root does not match the computed "
-                f"genesis state root.  Got {state.state_root}.  "
-                f"Expected {genesis_params['state_root']}"
+                f"genesis state root.  Got {state.state_root!r}.  "
+                f"Expected {genesis_params['state_root']!r}"
             )
 
         genesis_header = BlockHeader(**genesis_params)
@@ -438,8 +438,8 @@ def import_block(self,
         except HeaderNotFound:
             raise ValidationError(
                 f"Attempt to import block #{block.number}.  "
-                f"Cannot import block {block.hash} before importing "
-                f"its parent block at {block.header.parent_hash}"
+                f"Cannot import block {block.hash!r} before importing "
+                f"its parent block at {block.header.parent_hash!r}"
             )
 
         base_header_for_import = self.create_header_from_parent(parent_header)

eth/consensus/clique/_utils.py

@@ -139,10 +139,10 @@ def validate_header_integrity(header: BlockHeaderAPI, epoch_length: int) -> None
         )
 
     if header.nonce != NONCE_AUTH and header.nonce != NONCE_DROP:
-        raise ValidationError(f"Invalid nonce: {header.nonce}")
+        raise ValidationError(f"Invalid nonce: {header.nonce!r}")
 
     if at_checkpoint and header.nonce != NONCE_DROP:
-        raise ValidationError(f"Invalid checkpoint nonce: {header.nonce}")
+        raise ValidationError(f"Invalid checkpoint nonce: {header.nonce!r}")
 
     if len(header.extra_data) < VANITY_LENGTH:
         raise ValidationError("Missing vanity bytes in extra data")
@@ -159,7 +159,7 @@ def validate_header_integrity(header: BlockHeaderAPI, epoch_length: int) -> None
         raise ValidationError("Checkpoint header must contain list of signers")
 
     if header.mix_hash != ZERO_HASH32:
-        raise ValidationError(f"Invalid mix hash: {header.mix_hash}")
+        raise ValidationError(f"Invalid mix hash: {header.mix_hash!r}")
 
     if header.uncles_hash != EMPTY_UNCLE_HASH:
         raise ValidationError(f"Invalid uncle hash: {header.uncle_hash}")

eth/consensus/clique/datatypes.py

@@ -46,7 +46,7 @@ def validate_for(self,
         if not signer_is_kicked and not signer_is_nominated:
             raise ValidationError(
                 "Must either kick an existing signer or nominate a new signer"
-                f"Subject: {subject} Current signers: {signers}"
+                f"Subject: {subject!r} Current signers: {signers}"
             )
 
 

eth/consensus/clique/snapshot_manager.py

@@ -220,16 +220,16 @@ def get_snapshot(self, block_number: int, block_hash: Hash32) -> Snapshot:
                 # Otherwise, we can retrieve it on the fly
                 header = self._chain_db.get_block_header_by_hash(block_hash)
             except HeaderNotFound:
-                raise SnapshotNotFound(f"Can not get snapshot for {block_hash} at {block_number}")
+                raise SnapshotNotFound(f"Can not get snapshot for {block_hash!r} at {block_number}")
             else:
                 if header.block_number != block_number:
                     raise SnapshotNotFound(
-                        f"Can not get snapshot for {block_hash} at {block_number}"
+                        f"Can not get snapshot for {block_hash!r} at {block_number}"
                     )
                 else:
                     return self._create_snapshot_from_checkpoint_header(header)
 
-        raise SnapshotNotFound(f"Can not get snapshot for {block_hash} at {block_number}")
+        raise SnapshotNotFound(f"Can not get snapshot for {block_hash!r} at {block_number}")
 
     def add_snapshot(self, mutable_snapshot: MutableSnapshot) -> Snapshot:
         """
@@ -256,7 +256,7 @@ def get_snapshot_from_db(self, block_hash: Hash32) -> Snapshot:
             encoded_key = self._chain_db.db[key]
         except KeyError as e:
             raise SnapshotNotFound(
-                f"Can not get on-disk snapshot for {block_hash}"
+                f"Can not get on-disk snapshot for {block_hash!r}"
             )
         else:
             return decode_snapshot(encoded_key)

eth/db/chain.py

@@ -84,7 +84,7 @@ def get_block_uncles(self, uncles_hash: Hash32) -> Tuple[BlockHeaderAPI, ...]:
             encoded_uncles = self.db[uncles_hash]
         except KeyError:
             raise HeaderNotFound(
-                f"No uncles found for hash {uncles_hash}"
+                f"No uncles found for hash {uncles_hash!r}"
             )
         else:
             return tuple(rlp.decode(encoded_uncles, sedes=rlp.sedes.CountableList(BlockHeader)))

eth/tools/fixtures/helpers.py

@@ -76,13 +76,13 @@ def verify_state(expected_state: AccountState, state: StateAPI) -> None:
             if field == 'balance':
                 error_messages.append(
                     f"{to_normalized_address(account)}(balance) | "
-                    f"Actual: {actual_value} | Expected: {expected_value} | "
+                    f"Actual: {actual_value!r} | Expected: {expected_value!r} | "
                     f"Delta: {cast(int, actual_value) - cast(int, expected_value)}"
                 )
             else:
                 error_messages.append(
                     f"{to_normalized_address(account)}({field}) | "
-                    f"Actual: {actual_value} | Expected: {expected_value}"
+                    f"Actual: {actual_value!r} | Expected: {expected_value!r}"
                 )
         raise AssertionError(
             f"State DB did not match expected state on {len(error_messages)} values:{new_line}"

eth/validation.py

@@ -111,7 +111,7 @@ def validate_lt(value: int, maximum: int, title: str="Value") -> None:
 def validate_canonical_address(value: Address, title: str="Value") -> None:
     if not isinstance(value, bytes) or not len(value) == 20:
         raise ValidationError(
-            f"{title} {value} is not a valid canonical address"
+            f"{title} {value!r} is not a valid canonical address"
         )
 
 

eth/vm/base.py

@@ -507,7 +507,7 @@ def validate_block(self, block: BlockAPI) -> None:
         if tx_root_hash != block.header.transaction_root:
             raise ValidationError(
                 f"Block's transaction_root ({block.header.transaction_root}) "
-                f"does not match expected value: {tx_root_hash}"
+                f"does not match expected value: {tx_root_hash!r}"
             )
 
         if len(block.uncles) > MAX_UNCLES:

eth/vm/forks/frontier/validation.py

@@ -17,7 +17,7 @@ def validate_frontier_transaction(state: StateAPI,
 
     if sender_balance < gas_cost:
         raise ValidationError(
-            f"Sender {transaction.sender} cannot afford txn gas "
+            f"Sender {transaction.sender!r} cannot afford txn gas "
             f"{gas_cost} with account balance {sender_balance}"
         )
 

eth/vm/state.py

@@ -51,7 +51,7 @@ def __init__(
             self,
             db: AtomicDatabaseAPI,
             execution_context: ExecutionContextAPI,
-            state_root: bytes) -> None:
+            state_root: Hash32) -> None:
         self._db = db
         self.execution_context = execution_context
         self._account_db = self.get_account_db_class()(db, state_root)

setup.py

@@ -10,7 +10,7 @@
         "eth-bloom>=1.0.3,<2.0.0",
         "eth-keys>=0.2.1,<0.3.0",
         "eth-typing>=2.2.0,<3.0.0",
-        "eth-utils>=1.7.0,<2.0.0",
+        "eth-utils>=1.8.0,<2.0.0",
         "lru-dict>=1.1.6",
         "mypy_extensions>=0.4.1,<1.0.0",
         "py-ecc>=1.4.7,<2.0.0",
@@ -23,14 +23,14 @@
     # Installing these libraries may make the evm perform better than
     # using the default fallbacks though.
     'eth-extra': [
-        "coincurve>=10.0.0,<11.0.0",
+        "coincurve>=13.0.0,<14.0.0",
         "eth-hash[pysha3];implementation_name=='cpython'",
         "eth-hash[pycryptodome];implementation_name=='pypy'",
         "plyvel>=1.0.5,<1.2.0",
     ],
     'test': [
         "factory-boy==2.11.1",
-        "hypothesis==3.69.5",
+        "hypothesis==4.50.6",
         "pexpect>=4.6, <5",
         "pytest>=5.1.3,<6",
         "pytest-asyncio>=0.10.0,<0.11",
@@ -41,7 +41,7 @@
     'lint': [
         "flake8==3.5.0",
         "flake8-bugbear==18.8.0",
-        "mypy==0.701",
+        "mypy==0.750",
     ],
     'benchmark': [
         "termcolor>=1.1.0,<2.0.0",
@@ -115,5 +115,6 @@
         'Natural Language :: English',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
+        'Programming Language :: Python :: 3.8',
     ],
 )

tests/core/code-stream/test_code_stream.py

@@ -203,7 +203,10 @@ def test_new_vs_reference_code_stream_iter(bytecode):
     assert latest.program_counter == reference.program_counter
 
 
-@given(read_len=st.integers(min_value=0), bytecode=st.binary(max_size=128))
+@given(
+    read_len=st.integers(min_value=0, max_value=2048),
+    bytecode=st.binary(max_size=128)
+)
 def test_new_vs_reference_code_stream_read(read_len, bytecode):
     reference = SlowCodeStream(bytecode)
     latest = CodeStream(bytecode)
@@ -217,7 +220,7 @@ def test_new_vs_reference_code_stream_read(read_len, bytecode):
 
 @given(
     read_idx=st.integers(min_value=0, max_value=10),
-    read_len=st.integers(min_value=0),
+    read_len=st.integers(min_value=0, max_value=2048),
     bytecode=st.binary(max_size=128),
 )
 def test_new_vs_reference_code_stream_read_during_iter(read_idx, read_len, bytecode):

tox.ini

@@ -1,9 +1,9 @@
 [tox]
 envlist=
-    py{36,37}-{core,database,transactions,vm}
+    py{36,37,38}-{core,database,transactions,vm}
     py36-benchmark
     py36-native-blockchain-{frontier,homestead,tangerine_whistle,spurious_dragon,byzantium,constantinople,petersburg,istanbul,metropolis,transition}
-    py{36,37}-lint
+    py{36,37,38}-lint
     py36-docs
 
 [flake8]
@@ -41,6 +41,7 @@ deps =
 basepython =
     py36: python3.6
     py37: python3.7
+    py38: python3.8
 
 
 [testenv:py36-docs]