Optimize keccak() for raw bytes inputs

eth_utils/crypto.py

@@ -12,4 +12,13 @@ def keccak(
     hexstr: str | None = None,
     text: str | None = None,
 ) -> bytes:
+    if isinstance(primitive, bytes) and hexstr is None and text is None:
+        return bytes(keccak_256(primitive))
+    elif (
+        isinstance(primitive, (bytearray, memoryview))
+        and hexstr is None
+        and text is None
+    ):
+        return bytes(keccak_256(bytes(primitive)))
+
     return bytes(keccak_256(to_bytes(primitive, hexstr, text)))

newsfragments/95.performance.rst

@@ -0,0 +1,3 @@
+Reduced ``keccak()`` overhead for raw ``bytes``-like inputs by bypassing
+the generic conversion path when no ``hexstr`` or ``text`` argument is
+provided.

tests/core/crypto-utils/test_crypto.py

@@ -0,0 +1,38 @@
+import pytest
+
+from eth_hash.auto import (
+    keccak as raw_keccak,
+)
+
+import eth_utils.crypto as crypto_utils
+
+
+@pytest.mark.parametrize(
+    "kwargs,expected_payload",
+    (
+        ({"primitive": b"\x12\x34"}, b"\x12\x34"),
+        ({"primitive": bytearray(b"\x12\x34")}, b"\x12\x34"),
+        ({"primitive": memoryview(b"\x12\x34")}, b"\x12\x34"),
+        ({"hexstr": "0x1234"}, b"\x12\x34"),
+        ({"text": "ethereum"}, b"ethereum"),
+    ),
+)
+def test_keccak_matches_backend_for_supported_inputs(kwargs, expected_payload):
+    assert crypto_utils.keccak(**kwargs) == bytes(raw_keccak(expected_payload))
+
+
+def test_keccak_bytes_input_skips_to_bytes_conversion(monkeypatch):
+    def fail_if_called(*args, **kwargs):
+        raise AssertionError("to_bytes should not be called for raw bytes input")
+
+    monkeypatch.setattr(crypto_utils, "to_bytes", fail_if_called)
+
+    payload = b"\xde\xad\xbe\xef"
+    assert crypto_utils.keccak(payload) == bytes(raw_keccak(payload))
+
+
+def test_keccak_still_validates_multiple_input_sources():
+    with pytest.raises(
+        TypeError, match="Exactly one of the passed values can be specified"
+    ):
+        crypto_utils.keccak(b"\x12\x34", hexstr="0x1234")