Fix: Support all hash types in Prefix.sum()

cid/builder.py

@@ -1,7 +1,6 @@
 """Builder pattern for CID construction."""
 
 from abc import ABC, abstractmethod
-import hashlib
 from typing import TYPE_CHECKING
 
 import multihash
@@ -59,8 +58,7 @@ def sum(self, data: bytes) -> "CIDv0":
         """
         from .cid import CIDv0
 
-        digest = hashlib.sha256(data).digest()
-        mhash = multihash.encode(digest, "sha2-256")
+        mhash = multihash.sum(data, "sha2-256").encode()
         return CIDv0(mhash)
 
     def get_codec(self) -> str:
@@ -113,16 +111,8 @@ def sum(self, data: bytes) -> "CIDv1":
         """
         from .cid import CIDv1
 
-        if self.mh_type == "sha2-256":
-            digest = hashlib.sha256(data).digest()
-        elif self.mh_type == "sha2-512":
-            digest = hashlib.sha512(data).digest()
-        else:
-            msg = f"Hash type {self.mh_type} not fully implemented"
-            raise NotImplementedError(msg)
-
         mh_length = None if self.mh_length == -1 else self.mh_length
-        mhash = multihash.encode(digest, self.mh_type, mh_length)
+        mhash = multihash.sum(data, self.mh_type, length=mh_length).encode()
         return CIDv1(self.codec, mhash)
 
     def get_codec(self) -> str:

cid/prefix.py

@@ -1,6 +1,5 @@
 """CID Prefix operations for creating CIDs from data."""
 
-import hashlib
 from typing import TYPE_CHECKING
 
 import multicodec
@@ -111,22 +110,10 @@ def sum(self, data: bytes) -> "CIDv0 | CIDv1":
         :rtype: :py:class:`cid.CIDv0` or :py:class:`cid.CIDv1`
         :raises NotImplementedError: if hash type is not supported
         """
-        # Hash data using mh_type
-        if self.mh_type == "sha2-256":
-            digest = hashlib.sha256(data).digest()
-        elif self.mh_type == "sha2-512":
-            digest = hashlib.sha512(data).digest()
-        else:
-            # Use multihash library for other types
-            # This is a simplified implementation - in practice,
-            # you'd want to support more hash types
-            msg = f"Hash type {self.mh_type} not fully implemented"
-            raise NotImplementedError(msg)
-
         # Encode as multihash
         # Pass None if mh_length is -1 (default), otherwise use specified length
         mh_length = None if self.mh_length == -1 else self.mh_length
-        mhash = multihash.encode(digest, self.mh_type, mh_length)
+        mhash = multihash.sum(data, self.mh_type, length=mh_length).encode()
 
         # Create CID
         if self.version == 0:

newsfragments/64.bugfix.rst

@@ -0,0 +1 @@
+Support all standard hash types from multihash library in Prefix.sum().

tests/test_prefix.py

@@ -114,6 +114,26 @@ def test_v1_factory(self):
         assert prefix.codec == "raw"
         assert prefix.mh_type == "sha2-512"
 
+    @pytest.mark.parametrize(
+        "mh_type",
+        [
+            "sha2-256",
+            "sha2-512",
+            "sha3-256",
+            "sha3-512",
+            "blake2b-256",
+            "identity",
+        ],
+    )
+    def test_prefix_sum_various_hash_types(self, mh_type):
+        """Prefix.sum: correctly creates CID from various hash types"""
+        prefix = Prefix.v1(codec="raw", mh_type=mh_type)
+        cid = prefix.sum(b"hello world")
+        assert isinstance(cid, CIDv1)
+        assert cid.codec == "raw"
+        expected_type = "id" if mh_type == "identity" else mh_type
+        assert cid.prefix().mh_type == expected_type
+
 
 class TestCIDPrefix:
     """Tests for CID.prefix() method"""