feat(tests): eip-7883 & eip-7823 modexp cases

docs/CHANGELOG.md

@@ -60,6 +60,7 @@ Users can select any of the artifacts depending on their testing needs for their
 - 🔀 Refactored `SELFDESTRUCT` opcode collision tests to use the `pre_alloc` plugin in order to avoid contract and EOA address collisions ([#1643](https://github.com/ethereum/execution-spec-tests/pull/1643)).
 - ✨ EIP-7594: Sanity test cases to send blob transactions and verify `engine_getBlobsVX` using the `execute` command ([#1644](https://github.com/ethereum/execution-spec-tests/pull/1644)).
 - 🔀 Refactored EIP-145 static tests into python ([#1683](https://github.com/ethereum/execution-spec-tests/pull/1683)).
+- ✨ EIP-7823, EIP-7883: Add test cases for ModExp precompile gas-cost updates and input limits on Osaka ([#1579](https://github.com/ethereum/execution-spec-tests/pull/1579)).
 
 ## [v4.5.0](https://github.com/ethereum/execution-spec-tests/releases/tag/v4.5.0) - 2025-05-14
 

eels_resolutions.json

@@ -35,8 +35,13 @@
         "same_as": "EELSMaster"
     },
     "Prague": {
-      "git_url": "https://github.com/marioevz/execution-specs.git",
-      "branch": "forks/prague",
-      "commit": "bb0eb750d643ced0ebf5dec732cdd23558d0b7f2"
+        "git_url": "https://github.com/marioevz/execution-specs.git",
+        "branch": "forks/prague",
+        "commit": "bb0eb750d643ced0ebf5dec732cdd23558d0b7f2"
+    },
+    "Osaka": {
+        "git_url": "https://github.com/spencer-tb/execution-specs.git",
+        "branch": "forks/osaka",
+        "commit": "e59c6e3eaed0dbbca639b6f5b6acaa832e51ca00"
     }
 }

src/ethereum_test_types/helpers.py

@@ -1,9 +1,9 @@
 """Helper functions/classes used to generate Ethereum tests."""
 
-from dataclasses import MISSING, dataclass, fields
 from typing import List, SupportsBytes
 
 import ethereum_rlp as eth_rlp
+from pydantic import BaseModel, ConfigDict
 
 from ethereum_test_base_types.base_types import Address, Bytes, Hash
 from ethereum_test_base_types.conversions import BytesConvertible, FixedSizeBytesConvertible
@@ -93,8 +93,7 @@ def add_kzg_version(
     return kzg_versioned_hashes
 
 
-@dataclass(kw_only=True, frozen=True, repr=False)
-class TestParameterGroup:
+class TestParameterGroup(BaseModel):
     """
     Base class for grouping test parameters in a dataclass. Provides a generic
     __repr__ method to generate clean test ids, including only non-default
@@ -103,18 +102,18 @@ class TestParameterGroup:
 
     __test__ = False  # explicitly prevent pytest collecting this class
 
+    model_config = ConfigDict(frozen=True, validate_default=True)
+
     def __repr__(self):
         """
         Generate repr string, intended to be used as a test id, based on the class
         name and the values of the non-default optional fields.
         """
         class_name = self.__class__.__name__
-        field_strings = []
-
-        for field in fields(self):
-            value = getattr(self, field.name)
+        field_strings = [
+            f"{field}_{value}"
             # Include the field only if it is not optional or not set to its default value
-            if field.default is MISSING or field.default != value:
-                field_strings.append(f"{field.name}_{value}")
+            for field, value in self.model_dump(exclude_defaults=True, exclude_unset=True).items()
+        ]
 
         return f"{class_name}_{'-'.join(field_strings)}"

tests/byzantium/eip198_modexp_precompile/helpers.py

@@ -0,0 +1,91 @@
+"""Helper functions for the EIP-198 ModExp precompile tests."""
+
+from pydantic import Field
+
+from ethereum_test_tools import Bytes, TestParameterGroup
+
+
+class ModExpInput(TestParameterGroup):
+    """
+    Helper class that defines the MODEXP precompile inputs and creates the
+    call data from them.
+
+    Attributes:
+        base (str): The base value for the MODEXP precompile.
+        exponent (str): The exponent value for the MODEXP precompile.
+        modulus (str): The modulus value for the MODEXP precompile.
+        extra_data (str): Defines extra padded data to be added at the end of the calldata
+            to the precompile. Defaults to an empty string.
+
+    """
+
+    base: Bytes
+    exponent: Bytes
+    modulus: Bytes
+    extra_data: Bytes = Field(default_factory=Bytes)
+
+    @property
+    def length_base(self) -> Bytes:
+        """Return the length of the base."""
+        return Bytes(len(self.base).to_bytes(32, "big"))
+
+    @property
+    def length_exponent(self) -> Bytes:
+        """Return the length of the exponent."""
+        return Bytes(len(self.exponent).to_bytes(32, "big"))
+
+    @property
+    def length_modulus(self) -> Bytes:
+        """Return the length of the modulus."""
+        return Bytes(len(self.modulus).to_bytes(32, "big"))
+
+    def __bytes__(self):
+        """Generate input for the MODEXP precompile."""
+        return (
+            self.length_base
+            + self.length_exponent
+            + self.length_modulus
+            + self.base
+            + self.exponent
+            + self.modulus
+            + self.extra_data
+        )
+
+    @classmethod
+    def from_bytes(cls, input_data: Bytes | str) -> "ModExpInput":
+        """
+        Create a ModExpInput from a bytes object.
+
+        Assumes correct formatting of the input data.
+        """
+        if isinstance(input_data, str):
+            input_data = Bytes(input_data)
+        base_length = int.from_bytes(input_data[0:32], byteorder="big")
+        exponent_length = int.from_bytes(input_data[32:64], byteorder="big")
+        modulus_length = int.from_bytes(input_data[64:96], byteorder="big")
+
+        current_index = 96
+        base = input_data[current_index : current_index + base_length]
+        current_index += base_length
+
+        exponent = input_data[current_index : current_index + exponent_length]
+        current_index += exponent_length
+
+        modulus = input_data[current_index : current_index + modulus_length]
+
+        return cls(base=base, exponent=exponent, modulus=modulus)
+
+
+class ModExpOutput(TestParameterGroup):
+    """
+    Expected test result.
+
+    Attributes:
+        call_success (bool): The return_code from CALL, 0 indicates unsuccessful call
+            (out-of-gas), 1 indicates call succeeded.
+        returned_data (str): The output returnData is the expected output of the call
+
+    """
+
+    call_success: bool = True
+    returned_data: Bytes