Add type hints to web3.main

mypy.ini

@@ -0,0 +1,13 @@
+[mypy]
+warn_unused_ignores = True
+ignore_missing_imports = True
+strict_optional = False
+check_untyped_defs = True
+disallow_incomplete_defs = True
+disallow_untyped_defs = True
+disallow_any_generics = True
+; todo: disallow untyped calls after entire web3 codebase has type hints
+; disallow_untyped_calls = True
+warn_redundant_casts = True
+warn_unused_configs = True
+strict_equality = True

newsfragments/1488.misc.rst

@@ -0,0 +1 @@
+Start adding type hints to web3, beginning with web3.main

setup.py

@@ -13,6 +13,7 @@
     'linter': [
         "flake8==3.4.1",
         "isort>=4.2.15,<4.3.5",
+        "mypy==0.730",
     ],
     'docs': [
         "mock",

tox.ini

@@ -62,3 +62,4 @@ extras=linter
 commands=
   flake8 {toxinidir}/web3 {toxinidir}/ens {toxinidir}/ethpm {toxinidir}/tests
   isort --recursive --check-only --diff {toxinidir}/web3/ {toxinidir}/ens/ {toxinidir}/ethpm/ {toxinidir}/tests/
+  mypy -p web3.main --config-file {toxinidir}/mypy.ini

web3/main.py

@@ -15,6 +15,10 @@
 from hexbytes import (
     HexBytes,
 )
+from typing import Any, Dict, Iterable, List, TYPE_CHECKING, Union
+
+from eth_typing import HexStr, Primitives
+from eth_typing.abi import TypeStr
 
 from ens import ENS
 from web3._utils.abi import (
@@ -28,6 +32,7 @@
 )
 from web3._utils.empty import (
     empty,
+    Empty,
 )
 from web3._utils.encoding import (
     hex_encode_abi_type,
@@ -43,6 +48,9 @@
 from web3._utils.normalizers import (
     abi_ens_resolver,
 )
+from web3.datastructures import (
+    NamedElementOnion,
+)
 from web3.eth import (
     Eth,
 )
@@ -68,6 +76,9 @@
     ParityPersonal,
     ParityShh,
 )
+from web3.providers import (
+    BaseProvider,
+)
 from web3.providers.eth_tester import (
     EthereumTesterProvider,
 )
@@ -87,8 +98,11 @@
     Version,
 )
 
+if TYPE_CHECKING:
+    from web3.pm import PM  # noqa: F401
+
 
-def get_default_modules():
+def get_default_modules() -> Dict[str, Iterable[Any]]:
     return {
         "eth": (Eth,),
         "net": (Net,),
@@ -137,7 +151,13 @@ class Web3:
     isChecksumAddress = staticmethod(is_checksum_address)
     toChecksumAddress = staticmethod(to_checksum_address)
 
-    def __init__(self, provider=None, middlewares=None, modules=None, ens=empty):
+    def __init__(
+        self,
+        provider: BaseProvider=None,
+        middlewares: List[Any]=None,
+        modules: Dict[str, Iterable[Any]]=None,
+        ens: Union[ENS, Empty]=empty
+    ) -> None:
         self.manager = self.RequestManager(self, provider, middlewares)
 
         if modules is None:
@@ -150,35 +170,35 @@ def __init__(self, provider=None, middlewares=None, modules=None, ens=empty):
         self.ens = ens
 
     @property
-    def middleware_onion(self):
+    def middleware_onion(self) -> NamedElementOnion:
         return self.manager.middleware_onion
 
     @property
-    def provider(self):
+    def provider(self) -> BaseProvider:
         return self.manager.provider
 
     @provider.setter
-    def provider(self, provider):
+    def provider(self, provider: BaseProvider) -> None:
         self.manager.provider = provider
 
     @property
-    def clientVersion(self):
+    def clientVersion(self) -> int:
         return self.manager.request_blocking("web3_clientVersion", [])
 
     @property
-    def api(self):
+    def api(self) -> str:
         from web3 import __version__
         return __version__
 
     @staticmethod
     @deprecated_for("keccak")
     @apply_to_return_value(HexBytes)
-    def sha3(primitive=None, text=None, hexstr=None):
+    def sha3(primitive: Primitives=None, text: str=None, hexstr: HexStr=None) -> bytes:
         return Web3.keccak(primitive, text, hexstr)
 
     @staticmethod
     @apply_to_return_value(HexBytes)
-    def keccak(primitive=None, text=None, hexstr=None):
+    def keccak(primitive: Primitives=None, text: str=None, hexstr: HexStr=None) -> bytes:
         if isinstance(primitive, (bytes, int, type(None))):
             input_bytes = to_bytes(primitive, hexstr=hexstr, text=text)
             return eth_utils_keccak(input_bytes)
@@ -194,11 +214,11 @@ def keccak(primitive=None, text=None, hexstr=None):
 
     @combomethod
     @deprecated_for("solidityKeccak")
-    def soliditySha3(cls, abi_types, values):
+    def soliditySha3(cls, abi_types: List[TypeStr], values: List[Any]) -> bytes:
         return cls.solidityKeccak(abi_types, values)
 
     @combomethod
-    def solidityKeccak(cls, abi_types, values):
+    def solidityKeccak(cls, abi_types: List[TypeStr], values: List[Any]) -> bytes:
         """
         Executes keccak256 exactly as Solidity does.
         Takes list of abi_types as inputs -- `[uint24, int8[], bool]`
@@ -223,38 +243,39 @@ def solidityKeccak(cls, abi_types, values):
         ))
         return cls.keccak(hexstr=hex_string)
 
-    def isConnected(self):
+    def isConnected(self) -> bool:
         return self.provider.isConnected()
 
-    def is_encodable(self, _type, value):
+    def is_encodable(self, _type: TypeStr, value: Any) -> bool:
         return self.codec.is_encodable(_type, value)
 
     @property
-    def ens(self):
+    def ens(self) -> Union[ENS, Empty]:
         if self._ens is empty:
             return ENS.fromWeb3(self)
         else:
             return self._ens
 
     @ens.setter
-    def ens(self, new_ens):
+    def ens(self, new_ens: Union[ENS, Empty]) -> None:
         self._ens = new_ens
 
     @property
-    def pm(self):
+    def pm(self) -> "PM":
         if hasattr(self, '_pm'):
-            return self._pm
+            # ignored b/c property is dynamically set via enable_unstable_package_management_api
+            return self._pm  # type: ignore
         else:
             raise AttributeError(
                 "The Package Management feature is disabled by default until "
                 "its API stabilizes. To use these features, please enable them by running "
                 "`w3.enable_unstable_package_management_api()` and try again."
             )
 
-    def enable_unstable_package_management_api(self):
-        from web3.pm import PM
+    def enable_unstable_package_management_api(self) -> None:
+        from web3.pm import PM  # noqa: F811
         if not hasattr(self, '_pm'):
             PM.attach(self, '_pm')
 
-    def enable_strict_bytes_type_checking(self):
+    def enable_strict_bytes_type_checking(self) -> None:
         self.codec = ABICodec(build_strict_registry())