From f67704d280b0749ca65407c0c45016e1b11b21d5 Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 21 Aug 2025 19:22:21 +0200
Subject: [PATCH 01/14] feat(fixtures): add `executionWitness` to
 `FixtureBlockBase`

---
 src/ethereum_test_fixtures/blockchain.py | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/ethereum_test_fixtures/blockchain.py b/src/ethereum_test_fixtures/blockchain.py
index 3cd0b848d17..7ea7c5c9982 100644
--- a/src/ethereum_test_fixtures/blockchain.py
+++ b/src/ethereum_test_fixtures/blockchain.py
@@ -1,5 +1,7 @@
 """BlockchainTest types."""
 
+import json
+from dataclasses import dataclass
 from functools import cached_property
 from typing import (
     Annotated,
@@ -401,6 +403,21 @@ def from_withdrawal(cls, w: WithdrawalGeneric) -> "FixtureWithdrawal":
         return cls(**w.model_dump())
 
 
+@dataclass(slots=True)
+class WitnessChunk:
+    """Represents execution witness data for a block."""
+
+    state: List[str]
+    codes: List[str]
+    keys: List[str]
+    headers: List[str]
+
+    @classmethod
+    def from_json(cls, s: str) -> List["WitnessChunk"]:
+        """Parse witness chunks from JSON string."""
+        return [cls(**obj) for obj in json.loads(s)]
+
+
 class FixtureBlockBase(CamelModel):
     """Representation of an Ethereum block within a test Fixture without RLP bytes."""
 
@@ -408,6 +425,7 @@ class FixtureBlockBase(CamelModel):
     txs: List[FixtureTransaction] = Field(default_factory=list, alias="transactions")
     ommers: List[FixtureHeader] = Field(default_factory=list, alias="uncleHeaders")
     withdrawals: List[FixtureWithdrawal] | None = None
+    execution_witness: WitnessChunk | None = Field(None, alias="executionWitness")
 
     @computed_field(alias="blocknumber")  # type: ignore[misc]
     @cached_property

From 3f5be35863fb442e8caf996625e02ac2f0a51f26 Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 21 Aug 2025 19:31:23 +0200
Subject: [PATCH 02/14] feat(fill): add a plugin for execution witness
 generation

---
 src/pytest_plugins/filler/witness.py | 107 +++++++++++++++++++++++++++
 1 file changed, 107 insertions(+)
 create mode 100644 src/pytest_plugins/filler/witness.py

diff --git a/src/pytest_plugins/filler/witness.py b/src/pytest_plugins/filler/witness.py
new file mode 100644
index 00000000000..eb3a4abd494
--- /dev/null
+++ b/src/pytest_plugins/filler/witness.py
@@ -0,0 +1,107 @@
+"""
+Pytest plugin for witness functionality.
+
+Provides --witness command-line option that installs the witness-filler tool
+and generates execution witness data for blockchain test fixtures when enabled.
+"""
+
+import subprocess
+from typing import Any, Callable
+
+import pytest
+
+from ethereum_test_fixtures.blockchain import FixtureBlock, WitnessChunk
+
+
+def pytest_addoption(parser: pytest.Parser):
+    """Add witness command-line options to pytest."""
+    witness_group = parser.getgroup("witness", "Arguments for witness functionality")
+    witness_group.addoption(
+        "--witness",
+        action="store_true",
+        dest="witness",
+        default=False,
+        help=(
+            "Install the witness-filler tool and generate execution witness data for blockchain "
+            "test fixtures"
+        ),
+    )
+
+
+def pytest_configure(config):
+    """
+    Pytest hook called after command line options have been parsed.
+
+    If --witness is enabled, installs the witness-filler tool from the specified
+    git repository.
+    """
+    if config.getoption("witness"):
+        print("🔧 Installing witness-filler tool from kevaundray/reth...")
+        print("   This may take several minutes for first-time compilation...")
+
+        result = subprocess.run(
+            [
+                "cargo",
+                "install",
+                "--git",
+                "https://github.com/kevaundray/reth.git",
+                "--rev",
+                "8016a8a5736e4427b3d285c82cd39c4ece70f8c4",
+                "witness-filler",
+            ],
+        )
+
+        if result.returncode != 0:
+            pytest.exit(
+                f"Failed to install witness-filler tool (exit code: {result.returncode}). "
+                "Please ensure you have a compatible Rust toolchain installed. "
+                "You may need to update your Rust version to 1.86+ or run without --witness.",
+                1,
+            )
+        else:
+            print("✅ witness-filler tool installed successfully!")
+
+
+@pytest.fixture
+def witness_generator(request: pytest.FixtureRequest) -> Callable[[Any], None] | None:
+    """
+    Provide a witness generator function if --witness is enabled.
+
+    Returns:
+        None if witness functionality is disabled.
+        Callable that generates witness data for a fixture if enabled.
+
+    """
+    if not request.config.getoption("witness"):
+        return None
+
+    def generate_witness(fixture: Any) -> None:
+        """Generate witness data for a fixture using the witness-filler tool."""
+        if not hasattr(fixture, "blocks") or not fixture.blocks:
+            return
+
+        result = subprocess.run(
+            ["witness-filler"],
+            input=fixture.model_dump_json(by_alias=True),
+            text=True,
+            capture_output=True,
+        )
+
+        if result.returncode != 0:
+            raise RuntimeError(
+                f"witness-filler tool failed with exit code {result.returncode}. "
+                f"stderr: {result.stderr}"
+            )
+
+        try:
+            witnesses = WitnessChunk.from_json(result.stdout)
+            for i, witness in enumerate(witnesses):
+                if i < len(fixture.blocks) and isinstance(fixture.blocks[i], FixtureBlock):
+                    fixture.blocks[i].execution_witness = witness
+        except (ValueError, IndexError, AttributeError) as e:
+            raise RuntimeError(
+                f"Failed to parse witness data from witness-filler tool. "
+                f"Output was: {result.stdout[:500]}{'...' if len(result.stdout) > 500 else ''}"
+            ) from e
+
+    return generate_witness

From 6e4d8ee8cf482ce2b11d89798489360f0780d4ce Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 21 Aug 2025 19:33:08 +0200
Subject: [PATCH 03/14] feat(fill): use the `generate_witness` fixture in the
 `filler` plugin

---
 src/cli/pytest_commands/pytest_ini_files/pytest-fill.ini | 1 +
 src/pytest_plugins/filler/filler.py                      | 5 +++++
 2 files changed, 6 insertions(+)

diff --git a/src/cli/pytest_commands/pytest_ini_files/pytest-fill.ini b/src/cli/pytest_commands/pytest_ini_files/pytest-fill.ini
index dcdab775d66..84915897eb4 100644
--- a/src/cli/pytest_commands/pytest_ini_files/pytest-fill.ini
+++ b/src/cli/pytest_commands/pytest_ini_files/pytest-fill.ini
@@ -12,6 +12,7 @@ addopts =
     -p pytest_plugins.concurrency
     -p pytest_plugins.filler.pre_alloc
     -p pytest_plugins.filler.filler
+    -p pytest_plugins.filler.witness
     -p pytest_plugins.shared.execute_fill
     -p pytest_plugins.filler.ported_tests
     -p pytest_plugins.filler.static_filler
diff --git a/src/pytest_plugins/filler/filler.py b/src/pytest_plugins/filler/filler.py
index b96ec252a34..83d8e94812e 100644
--- a/src/pytest_plugins/filler/filler.py
+++ b/src/pytest_plugins/filler/filler.py
@@ -1140,6 +1140,7 @@ def base_test_parametrizer_func(
         test_case_description: str,
         fixture_source_url: str,
         gas_benchmark_value: int,
+        witness_generator,
     ):
         """
         Fixture used to instantiate an auto-fillable BaseTest object from within
@@ -1223,6 +1224,10 @@ def __init__(self, *args, **kwargs):
                     _info_metadata=t8n._info_metadata,
                 )
 
+                # Generate witness data if witness functionality is enabled via the witness plugin
+                if witness_generator is not None:
+                    witness_generator(fixture)
+
                 fixture_path = fixture_collector.add_fixture(
                     node_to_test_info(request.node),
                     fixture,

From c43c1ba94728036ca2df5f6f0119d344eb5c722b Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 21 Aug 2025 19:40:00 +0200
Subject: [PATCH 04/14] feat(fill,help): enable witness plugin help output to
 `fill --help`.

---
 src/pytest_plugins/help/help.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/pytest_plugins/help/help.py b/src/pytest_plugins/help/help.py
index aaa55960bd4..b70c0357a55 100644
--- a/src/pytest_plugins/help/help.py
+++ b/src/pytest_plugins/help/help.py
@@ -87,6 +87,7 @@ def pytest_configure(config):
                 "defining debug",
                 "pre-allocation behavior during test filling",
                 "ported",
+                "witness",
             ],
         )
     elif config.getoption("show_consume_help"):

From d2eddbfa417e2203547bf5a341a7e765ebf88d87 Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 21 Aug 2025 19:41:47 +0200
Subject: [PATCH 05/14] chore(fill): fix punctuation in witness plugin help
 string

---
 src/pytest_plugins/filler/witness.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/pytest_plugins/filler/witness.py b/src/pytest_plugins/filler/witness.py
index eb3a4abd494..1ed0178a53f 100644
--- a/src/pytest_plugins/filler/witness.py
+++ b/src/pytest_plugins/filler/witness.py
@@ -18,12 +18,13 @@ def pytest_addoption(parser: pytest.Parser):
     witness_group = parser.getgroup("witness", "Arguments for witness functionality")
     witness_group.addoption(
         "--witness",
+        "--witness-the-fitness",
         action="store_true",
         dest="witness",
         default=False,
         help=(
             "Install the witness-filler tool and generate execution witness data for blockchain "
-            "test fixtures"
+            "test fixtures."
         ),
     )
 

From a2bb2b1c9cc0a9cde0eab5724e99914a956f6dbf Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 21 Aug 2025 19:48:04 +0200
Subject: [PATCH 06/14] chore(fill): add hotfix to generate_witness for Paris

The `witness-filler` tool doesn't recognise Paris: Re-write `fixture.fork` to Merge if its value is Paris and then write it back to Paris afterwards.
---
 src/pytest_plugins/filler/witness.py | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/src/pytest_plugins/filler/witness.py b/src/pytest_plugins/filler/witness.py
index 1ed0178a53f..29f9166c677 100644
--- a/src/pytest_plugins/filler/witness.py
+++ b/src/pytest_plugins/filler/witness.py
@@ -81,12 +81,23 @@ def generate_witness(fixture: Any) -> None:
         if not hasattr(fixture, "blocks") or not fixture.blocks:
             return
 
-        result = subprocess.run(
-            ["witness-filler"],
-            input=fixture.model_dump_json(by_alias=True),
-            text=True,
-            capture_output=True,
-        )
+        # Hotfix: witness-filler expects "Merge" but execution-spec-tests uses "Paris"
+        original_fork = None
+        if hasattr(fixture, "fork") and str(fixture.fork) == "Paris":
+            original_fork = fixture.fork
+            fixture.fork = "Merge"
+
+        try:
+            result = subprocess.run(
+                ["witness-filler"],
+                input=fixture.model_dump_json(by_alias=True),
+                text=True,
+                capture_output=True,
+            )
+        finally:
+            # Restore original fork value
+            if original_fork is not None:
+                fixture.fork = original_fork
 
         if result.returncode != 0:
             raise RuntimeError(

From 9be75e81ae54dd5890774a6218afcc1092a6fd20 Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 21 Aug 2025 19:59:04 +0200
Subject: [PATCH 07/14] docs: update changelog

---
 docs/CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index a6d9e2f2df2..ff099700426 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -87,6 +87,7 @@ Users can select any of the artifacts depending on their testing needs for their
 - 💥 Flag `--flat-output` has been removed due to having been unneeded for an extended period of time ([#2018](https://github.com/ethereum/execution-spec-tests/pull/2018)).
 - ✨ Add support for `BlockchainEngineSyncFixture` format for tests marked with `pytest.mark.verify_sync` to enable client synchronization testing via `consume sync` command ([#2007](https://github.com/ethereum/execution-spec-tests/pull/2007)).
 - ✨ Framework is updated to include BPO ([EIP-7892](https://eips.ethereum.org/EIPS/eip-7892)) fork markers to enable the filling of BPO tests ([#2050](https://github.com/ethereum/execution-spec-tests/pull/2050)).
+- ✨ Generate and include execution witness data in blockchain fixtures if `--witness` is specified ([#2066](https://github.com/ethereum/execution-spec-tests/pull/2066)).
 
 #### `consume`
 

From 4bb601933abe64c8b2b89e1996ab4b743ab58f1f Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Mon, 25 Aug 2025 13:39:22 +0200
Subject: [PATCH 08/14] fill: update witness-filler ref as requested by jsign

---
 src/pytest_plugins/filler/witness.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pytest_plugins/filler/witness.py b/src/pytest_plugins/filler/witness.py
index 29f9166c677..370f3dc5542 100644
--- a/src/pytest_plugins/filler/witness.py
+++ b/src/pytest_plugins/filler/witness.py
@@ -47,7 +47,7 @@ def pytest_configure(config):
                 "--git",
                 "https://github.com/kevaundray/reth.git",
                 "--rev",
-                "8016a8a5736e4427b3d285c82cd39c4ece70f8c4",
+                "e7efffd314a003018883caf2489c39733fc59388",
                 "witness-filler",
             ],
         )

From 9de840191abc387b1221cabc8f5ddf43d59c8189 Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Mon, 25 Aug 2025 13:48:12 +0200
Subject: [PATCH 09/14] fixtures: change WitnessChunk from dataclass to
 CamelModel

---
 src/ethereum_test_fixtures/blockchain.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/ethereum_test_fixtures/blockchain.py b/src/ethereum_test_fixtures/blockchain.py
index 7ea7c5c9982..ddc82d14c68 100644
--- a/src/ethereum_test_fixtures/blockchain.py
+++ b/src/ethereum_test_fixtures/blockchain.py
@@ -1,7 +1,6 @@
 """BlockchainTest types."""
 
 import json
-from dataclasses import dataclass
 from functools import cached_property
 from typing import (
     Annotated,
@@ -403,8 +402,7 @@ def from_withdrawal(cls, w: WithdrawalGeneric) -> "FixtureWithdrawal":
         return cls(**w.model_dump())
 
 
-@dataclass(slots=True)
-class WitnessChunk:
+class WitnessChunk(CamelModel):
     """Represents execution witness data for a block."""
 
     state: List[str]

From c8d28dae1779bbaa21b8032da8b6d797bb7d11fb Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Mon, 25 Aug 2025 13:53:13 +0200
Subject: [PATCH 10/14] fixtures: rename WitnessChunk json parser helper method

---
 src/ethereum_test_fixtures/blockchain.py | 8 ++++++--
 src/pytest_plugins/filler/witness.py     | 2 +-
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/ethereum_test_fixtures/blockchain.py b/src/ethereum_test_fixtures/blockchain.py
index ddc82d14c68..545dec6b74d 100644
--- a/src/ethereum_test_fixtures/blockchain.py
+++ b/src/ethereum_test_fixtures/blockchain.py
@@ -411,8 +411,12 @@ class WitnessChunk(CamelModel):
     headers: List[str]
 
     @classmethod
-    def from_json(cls, s: str) -> List["WitnessChunk"]:
-        """Parse witness chunks from JSON string."""
+    def parse_witness_chunks(cls, s: str) -> List["WitnessChunk"]:
+        """
+        Parse multiple witness chunks from JSON string.
+
+        Returns a list of WitnessChunk instances parsed from the JSON array.
+        """
         return [cls(**obj) for obj in json.loads(s)]
 
 
diff --git a/src/pytest_plugins/filler/witness.py b/src/pytest_plugins/filler/witness.py
index 370f3dc5542..453afb2fa48 100644
--- a/src/pytest_plugins/filler/witness.py
+++ b/src/pytest_plugins/filler/witness.py
@@ -106,7 +106,7 @@ def generate_witness(fixture: Any) -> None:
             )
 
         try:
-            witnesses = WitnessChunk.from_json(result.stdout)
+            witnesses = WitnessChunk.parse_witness_chunks(result.stdout)
             for i, witness in enumerate(witnesses):
                 if i < len(fixture.blocks) and isinstance(fixture.blocks[i], FixtureBlock):
                     fixture.blocks[i].execution_witness = witness

From 14494fdb15591d5fad85e4f6f4e713db702abfd8 Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Mon, 25 Aug 2025 17:13:14 +0200
Subject: [PATCH 11/14] fill: add a WitnessFillerResult to validate
 witness-filler output

---
 src/pytest_plugins/filler/witness.py | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/pytest_plugins/filler/witness.py b/src/pytest_plugins/filler/witness.py
index 453afb2fa48..f839666742b 100644
--- a/src/pytest_plugins/filler/witness.py
+++ b/src/pytest_plugins/filler/witness.py
@@ -6,13 +6,20 @@
 """
 
 import subprocess
-from typing import Any, Callable
+from typing import Any, Callable, List
 
 import pytest
 
+from ethereum_test_base_types import EthereumTestRootModel
 from ethereum_test_fixtures.blockchain import FixtureBlock, WitnessChunk
 
 
+class WitnessFillerResult(EthereumTestRootModel[List[WitnessChunk]]):
+    """Model that defines the expected result from the `witness-filler` command."""
+
+    root: List[WitnessChunk]
+
+
 def pytest_addoption(parser: pytest.Parser):
     """Add witness command-line options to pytest."""
     witness_group = parser.getgroup("witness", "Arguments for witness functionality")
@@ -106,11 +113,13 @@ def generate_witness(fixture: Any) -> None:
             )
 
         try:
-            witnesses = WitnessChunk.parse_witness_chunks(result.stdout)
+            result_model = WitnessFillerResult.model_validate_json(result.stdout)
+            witnesses = result_model.root
+
             for i, witness in enumerate(witnesses):
                 if i < len(fixture.blocks) and isinstance(fixture.blocks[i], FixtureBlock):
                     fixture.blocks[i].execution_witness = witness
-        except (ValueError, IndexError, AttributeError) as e:
+        except Exception as e:
             raise RuntimeError(
                 f"Failed to parse witness data from witness-filler tool. "
                 f"Output was: {result.stdout[:500]}{'...' if len(result.stdout) > 500 else ''}"

From 7ead93ce8a52db60ead8fc9d59ec866bef1e8237 Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 28 Aug 2025 16:55:08 +0200
Subject: [PATCH 12/14] refactor(fill): improve `generate_witness` fixture &
 fork checks

1. Avoid `hasattr` by checking that the provided fixture is of the required pydantic model type (`BlockchainFixture`).
2. Add a clean solution for the `witness-filler` fork naming incompatibility by subclassing `Paris` as `Merge`.
---
 src/pytest_plugins/filler/witness.py | 42 +++++++++++++++++++---------
 1 file changed, 29 insertions(+), 13 deletions(-)

diff --git a/src/pytest_plugins/filler/witness.py b/src/pytest_plugins/filler/witness.py
index f839666742b..86ab7a1b474 100644
--- a/src/pytest_plugins/filler/witness.py
+++ b/src/pytest_plugins/filler/witness.py
@@ -6,12 +6,13 @@
 """
 
 import subprocess
-from typing import Any, Callable, List
+from typing import Callable, List
 
 import pytest
 
 from ethereum_test_base_types import EthereumTestRootModel
-from ethereum_test_fixtures.blockchain import FixtureBlock, WitnessChunk
+from ethereum_test_fixtures.blockchain import BlockchainFixture, FixtureBlock, WitnessChunk
+from ethereum_test_forks import Paris
 
 
 class WitnessFillerResult(EthereumTestRootModel[List[WitnessChunk]]):
@@ -20,6 +21,18 @@ class WitnessFillerResult(EthereumTestRootModel[List[WitnessChunk]]):
     root: List[WitnessChunk]
 
 
+class Merge(Paris):
+    """
+    Paris fork that serializes as 'Merge' for witness-filler compatibility.
+
+    IMPORTANT: This class MUST be named 'Merge' (not 'MergeForWitness' or similar)
+    because the class name is used directly in Pydantic serialization, and
+    witness-filler expects exactly 'Merge' for this fork.
+    """
+
+    pass
+
+
 def pytest_addoption(parser: pytest.Parser):
     """Add witness command-line options to pytest."""
     witness_group = parser.getgroup("witness", "Arguments for witness functionality")
@@ -71,28 +84,30 @@ def pytest_configure(config):
 
 
 @pytest.fixture
-def witness_generator(request: pytest.FixtureRequest) -> Callable[[Any], None] | None:
+def witness_generator(
+    request: pytest.FixtureRequest,
+) -> Callable[[BlockchainFixture], None] | None:
     """
     Provide a witness generator function if --witness is enabled.
 
     Returns:
         None if witness functionality is disabled.
-        Callable that generates witness data for a fixture if enabled.
+        Callable that generates witness data for a BlockchainFixture if enabled.
 
     """
     if not request.config.getoption("witness"):
         return None
 
-    def generate_witness(fixture: Any) -> None:
-        """Generate witness data for a fixture using the witness-filler tool."""
-        if not hasattr(fixture, "blocks") or not fixture.blocks:
-            return
+    def generate_witness(fixture: BlockchainFixture) -> None:
+        """Generate witness data for a blockchain fixture using the witness-filler tool."""
+        if not isinstance(fixture, BlockchainFixture):
+            return None
 
         # Hotfix: witness-filler expects "Merge" but execution-spec-tests uses "Paris"
         original_fork = None
-        if hasattr(fixture, "fork") and str(fixture.fork) == "Paris":
+        if fixture.fork is Paris:
             original_fork = fixture.fork
-            fixture.fork = "Merge"
+            fixture.fork = Merge
 
         try:
             result = subprocess.run(
@@ -102,7 +117,6 @@ def generate_witness(fixture: Any) -> None:
                 capture_output=True,
             )
         finally:
-            # Restore original fork value
             if original_fork is not None:
                 fixture.fork = original_fork
 
@@ -117,8 +131,10 @@ def generate_witness(fixture: Any) -> None:
             witnesses = result_model.root
 
             for i, witness in enumerate(witnesses):
-                if i < len(fixture.blocks) and isinstance(fixture.blocks[i], FixtureBlock):
-                    fixture.blocks[i].execution_witness = witness
+                if i < len(fixture.blocks):
+                    block = fixture.blocks[i]
+                    if isinstance(block, FixtureBlock):
+                        block.execution_witness = witness
         except Exception as e:
             raise RuntimeError(
                 f"Failed to parse witness data from witness-filler tool. "

From bd5c72a5cf7c435f126acfe21329894d1e426673 Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 28 Aug 2025 17:05:45 +0200
Subject: [PATCH 13/14] chore(fixtures): remove unncessary pydantic field alias

---
 src/ethereum_test_fixtures/blockchain.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/ethereum_test_fixtures/blockchain.py b/src/ethereum_test_fixtures/blockchain.py
index 545dec6b74d..61688a4c3dc 100644
--- a/src/ethereum_test_fixtures/blockchain.py
+++ b/src/ethereum_test_fixtures/blockchain.py
@@ -427,7 +427,7 @@ class FixtureBlockBase(CamelModel):
     txs: List[FixtureTransaction] = Field(default_factory=list, alias="transactions")
     ommers: List[FixtureHeader] = Field(default_factory=list, alias="uncleHeaders")
     withdrawals: List[FixtureWithdrawal] | None = None
-    execution_witness: WitnessChunk | None = Field(None, alias="executionWitness")
+    execution_witness: WitnessChunk | None = None
 
     @computed_field(alias="blocknumber")  # type: ignore[misc]
     @cached_property

From 6c4551a9d6adc59e41ab160385d6bd50e0bac56e Mon Sep 17 00:00:00 2001
From: danceratopz <danceratopz@gmail.com>
Date: Thu, 28 Aug 2025 21:02:16 +0200
Subject: [PATCH 14/14] chore(fill): exit on error if witness-filler is
 unavailable

Don't build it using cargo install; this must be done by the user.
---
 src/pytest_plugins/filler/witness.py | 37 +++++++++-------------------
 1 file changed, 11 insertions(+), 26 deletions(-)

diff --git a/src/pytest_plugins/filler/witness.py b/src/pytest_plugins/filler/witness.py
index 86ab7a1b474..fc21e3dceeb 100644
--- a/src/pytest_plugins/filler/witness.py
+++ b/src/pytest_plugins/filler/witness.py
@@ -1,10 +1,11 @@
 """
 Pytest plugin for witness functionality.
 
-Provides --witness command-line option that installs the witness-filler tool
+Provides --witness command-line option that checks for the witness-filler tool in PATH
 and generates execution witness data for blockchain test fixtures when enabled.
 """
 
+import shutil
 import subprocess
 from typing import Callable, List
 
@@ -43,8 +44,8 @@ def pytest_addoption(parser: pytest.Parser):
         dest="witness",
         default=False,
         help=(
-            "Install the witness-filler tool and generate execution witness data for blockchain "
-            "test fixtures."
+            "Generate execution witness data for blockchain test fixtures using the "
+            "witness-filler tool (must be installed separately)."
         ),
     )
 
@@ -53,34 +54,18 @@ def pytest_configure(config):
     """
     Pytest hook called after command line options have been parsed.
 
-    If --witness is enabled, installs the witness-filler tool from the specified
-    git repository.
+    If --witness is enabled, checks that the witness-filler tool is available in PATH.
     """
     if config.getoption("witness"):
-        print("🔧 Installing witness-filler tool from kevaundray/reth...")
-        print("   This may take several minutes for first-time compilation...")
-
-        result = subprocess.run(
-            [
-                "cargo",
-                "install",
-                "--git",
-                "https://github.com/kevaundray/reth.git",
-                "--rev",
-                "e7efffd314a003018883caf2489c39733fc59388",
-                "witness-filler",
-            ],
-        )
-
-        if result.returncode != 0:
+        # Check if witness-filler binary is available in PATH
+        if not shutil.which("witness-filler"):
             pytest.exit(
-                f"Failed to install witness-filler tool (exit code: {result.returncode}). "
-                "Please ensure you have a compatible Rust toolchain installed. "
-                "You may need to update your Rust version to 1.86+ or run without --witness.",
+                "witness-filler tool not found in PATH. Please build and install witness-filler "
+                "from https://github.com/kevaundray/reth.git before using --witness flag.\n"
+                "Example: cargo install --git https://github.com/kevaundray/reth.git "
+                "witness-filler",
                 1,
             )
-        else:
-            print("✅ witness-filler tool installed successfully!")
 
 
 @pytest.fixture