add a new feature to validate ethereum address

pyproject.toml

@@ -35,7 +35,9 @@ classifiers = [
 ]
 requires-python = ">=3.8"
 dynamic = ["version"]
-dependencies = []
+dependencies = [
+    "eth-hash[pycryptodome]>=0.7.0",
+]
 
 [project.urls]
 Homepage = "https://python-validators.github.io/validators"

src/validators/__init__.py

@@ -5,7 +5,7 @@
 from .card import amex, card_number, diners, discover, jcb, mastercard, unionpay, visa
 from .country import calling_code, country_code, currency
 from .cron import cron
-from .crypto_addresses.btc_address import btc_address
+from .crypto_addresses import btc_address, eth_address
 from .domain import domain
 from .email import email
 from .encoding import base58, base64
@@ -37,6 +37,7 @@
     # ...
     "between",
     "btc_address",
+    "eth_address",
     # cards
     "amex",
     "card_number",

src/validators/crypto_addresses/__init__.py

@@ -1 +1,7 @@
 """Crypto addresses."""
+
+# local
+from .btc_address import btc_address
+from .eth_address import eth_address
+
+__all__ = ("btc_address", "eth_address")

src/validators/crypto_addresses/eth_address.py

@@ -0,0 +1,54 @@
+"""ETH Address."""
+
+# standard
+import re
+
+# external
+from eth_hash.auto import keccak
+
+# local
+from validators.utils import validator
+
+
+def _validate_eth_checksum_address(addr: str):
+    """Validate ETH type checksum address."""
+    addr = addr.replace("0x", "")
+    addr_hash = keccak.new(addr.lower().encode("ascii")).digest().hex()
+
+    if len(addr) != 40:
+        return False
+
+    for i in range(0, 40):
+        if (int(addr_hash[i], 16) > 7 and addr[i].upper() != addr[i]) or (
+            int(addr_hash[i], 16) <= 7 and addr[i].lower() != addr[i]
+        ):
+            return False
+    return True
+
+
+@validator
+def eth_address(value: str, /):
+    """Return whether or not given value is a valid ethereum address.
+
+    Full validation is implemented for ERC20 addresses.
+
+    Examples:
+        >>> eth_address('0x9cc14ba4f9f68ca159ea4ebf2c292a808aaeb598')
+        # Output: True
+        >>> eth_address('0x8Ba1f109551bD432803012645Ac136ddd64DBa72')
+        # Output: ValidationError(func=eth_address, args=...)
+
+    Args:
+        value:
+            Ethereum address string to validate.
+
+    Returns:
+        (Literal[True]): If `value` is a valid ethereum address.
+        (ValidationError): If `value` is an invalid ethereum address.
+    """
+    if not value:
+        return False
+
+    return re.compile(r"^0x[0-9a-f]{40}$|^0x[0-9A-F]{40}$").match(
+        value
+    ) or _validate_eth_checksum_address(value)

tests/crypto_addresses/test_eth_address.py

@@ -0,0 +1,44 @@
+"""Test ETH address."""
+
+# external
+import pytest
+
+# local
+from validators import ValidationError, eth_address
+
+
+@pytest.mark.parametrize(
+    "value",
+    [
+        "0x8ba1f109551bd432803012645ac136ddd64dba72",
+        "0x9cc14ba4f9f68ca159ea4ebf2c292a808aaeb598",
+        "0x5AEDA56215b167893e80B4fE645BA6d5Bab767DE",
+        "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
+        "0x742d35Cc6634C0532925a3b844Bc454e4438f44e",
+        "0x1f9840a85d5aF5bf1D1762F925BDADdC4201F984",
+        "0x1234567890123456789012345678901234567890",
+        "0x57Ab1ec28D129707052df4dF418D58a2D46d5f51",
+    ],
+)
+def test_returns_true_on_valid_eth_address(value: str):
+    """Test returns true on valid eth address."""
+    assert eth_address(value)
+
+
+@pytest.mark.parametrize(
+    "value",
+    [
+        "0x742d35Cc6634C0532925a3b844Bc454e4438f44g",
+        "0x742d35Cc6634C0532925a3b844Bc454e4438f44",
+        "0xAbcdefg1234567890Abcdefg1234567890Abcdefg",
+        "0x7c8EE9977c6f96b6b9774b3e8e4Cc9B93B12b2c72",
+        "0x80fBD7F8B3f81D0e1d6EACAb69AF104A6508AFB1",
+        "0x7c8EE9977c6f96b6b9774b3e8e4Cc9B93B12b2c7g",
+        "0x7c8EE9977c6f96b6b9774b3e8e4Cc9B93B12b2c",
+        "0x7Fb21a171205f3B8d8E4d88A2d2f8A56E45DdB5c",
+        "validators.eth",
+    ],
+)
+def test_returns_failed_validation_on_invalid_eth_address(value: str):
+    """Test returns failed validation on invalid eth address."""
+    assert isinstance(eth_address(value), ValidationError)