diff options
Diffstat (limited to 'python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py')
-rw-r--r-- | python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py b/python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py index 08c1b0ea5..1dcfb39a9 100644 --- a/python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py +++ b/python-packages/order_utils/src/zero_ex/dev_utils/type_assertions.py @@ -2,6 +2,9 @@ from typing import Any +from eth_utils import is_address +from web3.providers.base import BaseProvider + def assert_is_string(value: Any, name: str) -> None: """If :param value: isn't of type str, raise a TypeError. @@ -56,3 +59,31 @@ def assert_is_hex_string(value: Any, name: str) -> None: """ assert_is_string(value, name) int(value, 16) # raises a ValueError if value isn't a base-16 str + + +def assert_is_address(value: Any, name: str) -> None: + """Assert that `value` is a valid Ethereum address. + + If `value` isn't a hex string, raise a TypeError. If it isn't a valid + Ethereum address, raise a ValueError. + """ + assert_is_hex_string(value, name) + if not is_address(value): + raise ValueError( + f"Expected variable '{name}' to be a valid Ethereum" + + " address, but it's not." + ) + + +def assert_is_provider(value: Any, name: str) -> None: + """Assert that `value` is a Web3 provider. + + If `value` isn't a Web3 provider, raise a TypeError. + """ + # TODO: make this provider check more flexible. + # https://app.asana.com/0/684263176955174/901300863045491/f + if not isinstance(value, BaseProvider): + raise TypeError( + f"Expected variable '{name}' to be an instance of a Web3 provider," + + " but it's not." + ) |