feat[lang]: add blobhash() builtin

docs/built-in-functions.rst

@@ -949,6 +949,30 @@ Utilities
         >>> ExampleContract.foo()
         0xf3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855
 
+.. py:function:: blobhash(index: uint256) -> bytes32
+
+    Return the versioned hash of the ``index``-th BLOB associated with the current transaction.
+
+    .. note::
+
+         A versioned hash consists of a single byte representing the version (currently ``0x01``), followed by the last 31 bytes of the ``SHA256`` hash of the KZG commitment (`EIP-4844 <https://eips.ethereum.org/EIPS/eip-4844>`_). For the case ``index >= len(tx.blob_versioned_hashes)``, `blobhash(index: uint256)` returns ``empty(bytes32)``.
+
+    .. code-block:: vyper
+
+        @external
+        @view
+        def foo(index: uint256) -> bytes32:
+            return blobhash(index)
+
+    .. code-block:: vyper
+
+        >>> ExampleContract.foo(0)
+        0xfd28610fb309939bfec12b6db7c4525446f596a5a5a66b8e2cb510b45b2bbeb5
+
+        >>> ExampleContract.foo(6)
+        0x0000000000000000000000000000000000000000000000000000000000000000
+
+
 .. py:function:: empty(typename) -> Any
 
     Return a value which is the default (zero-ed) value of its type. Useful for initializing new memory variables.

tests/functional/builtins/codegen/test_blobhash.py

@@ -0,0 +1,52 @@
+import pytest
+from pytest import raises
+
+from vyper import compiler
+from vyper.exceptions import EvmVersionException
+
+valid_list = [
+    """
+@external
+@view
+def foo() -> bytes32:
+    return blobhash(0)
+    """,
+    """
+@external
+@view
+def foo() -> bytes32:
+    a: bytes32 = 0x0000000000000000000000000000000000000000000000000000000000000005
+    a = blobhash(2)
+    return a
+    """,
+    """
+@external
+@view
+def foo() -> bytes32:
+    a: bytes32 = blobhash(5)
+    return a
+    """,
+    """
+@external
+@view
+def foo() -> bytes32:
+    a: bytes32 = blobhash(1337)
+    assert a == empty(bytes32)
+    return a
+    """,
+]
+
+
+@pytest.mark.requires_evm_version("cancun")
+@pytest.mark.parametrize("good_code", valid_list)
+def test_blobhash_success(good_code):
+    assert compiler.compile_code(good_code) is not None
+    assembly = compiler.compile_code(good_code, output_formats=["asm"])["asm"].split(" ")
+    assert "BLOBHASH" in assembly
+
+
+@pytest.mark.requires_evm_version("shanghai")
+@pytest.mark.parametrize("invalid_evm_version", valid_list)
+def test_blobhash_fail(invalid_evm_version):
+    with pytest.raises(EvmVersionException):
+        compiler.compile_code(invalid_evm_version)

vyper/builtins/functions.py

@@ -37,10 +37,12 @@
 from vyper.codegen.expr import Expr
 from vyper.codegen.ir_node import Encoding, scope_multi
 from vyper.codegen.keccak256_helper import keccak256_helper
+from vyper.evm.opcodes import version_check
 from vyper.evm.address_space import MEMORY
 from vyper.exceptions import (
     ArgumentException,
     CompilerPanic,
+    EvmVersionException,
     InvalidLiteral,
     InvalidType,
     StateAccessViolation,
@@ -1219,6 +1221,21 @@ def build_IR(self, expr, args, kwargs, contact):
         )
 
 
+class BlobHash(BuiltinFunctionT):
+    _id = "blobhash"
+    _inputs = [("index", UINT256_T)]
+    _return_type = BYTES32_T
+
+    @process_inputs
+    def build_IR(self, expr, args, kwargs, contact):
+        if not version_check(begin="cancun"):
+            raise EvmVersionException("`blobhash` is not available pre-cancun", expr)
+        return IRnode.from_list(
+            ["blockhash", args[0]],
+            typ=BYTES32_T,
+        )
+
+
 class RawRevert(BuiltinFunctionT):
     _id = "raw_revert"
     _inputs = [("data", BytesT.any())]
@@ -2591,6 +2608,7 @@ def _try_fold(self, node):
     "as_wei_value": AsWeiValue(),
     "raw_call": RawCall(),
     "blockhash": BlockHash(),
+    "blobhash": BlobHash(),
     "bitwise_and": BitwiseAnd(),
     "bitwise_or": BitwiseOr(),
     "bitwise_xor": BitwiseXor(),

vyper/evm/opcodes.py

@@ -75,6 +75,7 @@
     "CHAINID": (0x46, 0, 1, 2),
     "SELFBALANCE": (0x47, 0, 1, 5),
     "BASEFEE": (0x48, 0, 1, 2),
+    "BLOBHASH": (0x49, 1, 1, (None, None, None, 2)),
     "POP": (0x50, 1, 0, 2),
     "MLOAD": (0x51, 1, 1, 3),
     "MSTORE": (0x52, 2, 0, 3),

vyper/venom/ir_node_to_venom.py

@@ -76,6 +76,7 @@
         "balance",
         "msize",
         "basefee",
+        "blobhash",
         "invalid",
         "stop",
         "selfdestruct",

vyper/venom/venom_to_assembly.py

@@ -97,6 +97,7 @@
         "delegatecall",
         "codesize",
         "basefee",
+        "blobhash",
         "prevrandao",
         "difficulty",
         "invalid",