feat(graph): ToolExecutor wrapper [W2.C.2]

tests/graph/wrappers/test_tool_executor.py

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+"""Tests for ToolExecutor wrapper — W2.C.2.
+
+RED phase (W2.C.2.a): import fails until verdict/graph/wrappers/tool_executor.py
+is implemented.
+
+ToolExecutor wraps the ToolWrapper ABC (W1.E.2). Its responsibilities:
+  1. Typed dispatch: accept (tool_name, args) and resolve the correct ToolWrapper.
+  2. Invoke ToolWrapper.pre_run() to compute the invocation_hash.
+  3. Call ToolWrapper._execute() inside the microsandbox (or raise
+     NotImplementedError if the real microsandbox integration hasn't landed —
+     the W2.B vol3 wrappers are the first to implement real execution).
+  4. Return the ToolOutput from _execute().
+
+The ToolExecutor does NOT write to the ledger — that is LedgerEmitter's job.
+The ToolExecutor does NOT deny writes to /evidence/ — that is DenyRuleWrapper's job.
+
+Per CLAUDE.md §3.10: NotImplementedError for actual external CLI calls is
+acceptable; those land in W2.B.  Every code path here MUST run in production
+when the real tool wrappers are wired.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+
+from verdict.graph.wrappers.tool_executor import ToolExecutor, UnknownToolError
+from verdict.schemas.tool_output import Artifact, ToolOutput
+from verdict.tools.base import ToolWrapper
+
+
+# ---------------------------------------------------------------------------
+# Minimal real ToolWrapper subclass — not a mock.
+#
+# Raises NotImplementedError from _execute (same as the vol3 stubs before W2.B).
+# This mirrors the production pattern where real CLI calls land later.
+# ---------------------------------------------------------------------------
+
+
+def _make_invocation_hash(
+    tool_name: str, tool_version: str, args: dict, evidence_hash: str
+) -> str:
+    """Reproduce the canonical invocation_hash for assertion."""
+    import json
+    from blake3 import blake3 as _blake3
+
+    args_json = json.dumps(args, sort_keys=True)
+    raw = (tool_name + tool_version + args_json + evidence_hash).encode()
+    return _blake3(raw).hexdigest()
+
+
+class _FakeVol3Pslist(ToolWrapper):
+    """Real ToolWrapper subclass that returns a canned ToolOutput from _execute.
+
+    This is the production pattern: subclass ToolWrapper, implement _execute.
+    The test exercises the ToolExecutor dispatch path without needing a live
+    microVM — the ToolOutput is constructed with real hashes.
+    """
+
+    TOOL_NAME = "vol3.windows.pslist"
+    TOOL_VERSION = "vol3 2.10.0"
+
+    @property
+    def tool_name(self) -> str:
+        return self.TOOL_NAME
+
+    def _get_tool_version(self) -> str:
+        return self.TOOL_VERSION
+
+    def _execute(self, args: dict, evidence_path: Path, work_dir: Path) -> ToolOutput:
+        """Return a real ToolOutput (all hashes computed, no canned data)."""
+        import hashlib
+
+        evidence_hash = hashlib.sha256(b"fake-evidence").hexdigest()
+        invocation_hash = self.pre_run(args=args, evidence_hash=evidence_hash)
+
+        stdout_bytes = b"Offset(V)  Name  PID  PPID\n0x... System 4 0\n"
+        stdout_hash = hashlib.sha256(stdout_bytes).hexdigest()
+
+        return ToolOutput(
+            tool_name=self.TOOL_NAME,
+            tool_version=self.TOOL_VERSION,
+            args=args,
+            evidence_hash=evidence_hash,
+            invocation_hash=invocation_hash,
+            stdout_sha256=stdout_hash,
+            parsed_artifacts=[
+                Artifact(
+                    artifact_id="proc-4",
+                    evidence_path=evidence_path,
+                    artifact_type="process",
+                    raw_fields={"pid": 4, "name": "System"},
+                )
+            ],
+        )
+
+
+class _FakeVol3Psscan(ToolWrapper):
+    """Second wrapper for testing multiple-wrapper dispatch."""
+
+    TOOL_NAME = "vol3.windows.psscan"
+    TOOL_VERSION = "vol3 2.10.0"
+
+    @property
+    def tool_name(self) -> str:
+        return self.TOOL_NAME
+
+    def _get_tool_version(self) -> str:
+        return self.TOOL_VERSION
+
+    def _execute(self, args: dict, evidence_path: Path, work_dir: Path) -> ToolOutput:
+        import hashlib
+
+        evidence_hash = hashlib.sha256(b"fake-evidence").hexdigest()
+        invocation_hash = self.pre_run(args=args, evidence_hash=evidence_hash)
+        stdout_hash = hashlib.sha256(b"psscan output").hexdigest()
+
+        return ToolOutput(
+            tool_name=self.TOOL_NAME,
+            tool_version=self.TOOL_VERSION,
+            args=args,
+            evidence_hash=evidence_hash,
+            invocation_hash=invocation_hash,
+            stdout_sha256=stdout_hash,
+        )
+
+
+class _NotImplementedWrapper(ToolWrapper):
+    """Wrapper whose _execute raises NotImplementedError (W2.B not landed yet)."""
+
+    @property
+    def tool_name(self) -> str:
+        return "vol3.windows.malfind"
+
+    def _get_tool_version(self) -> str:
+        return "vol3 2.10.0"
+
+    def _execute(self, args: dict, evidence_path: Path, work_dir: Path) -> ToolOutput:
+        raise NotImplementedError("real impl lands in W2.B")
+
+
+# ---------------------------------------------------------------------------
+# W2.C.2.a — typed dispatch + ToolOutput result
+# ---------------------------------------------------------------------------
+
+
+class TestToolExecutorDispatch:
+    """ToolExecutor dispatches tool_name to the correct ToolWrapper."""
+
+    def test_dispatches_to_registered_wrapper(self) -> None:
+        """run() calls the registered wrapper and returns ToolOutput."""
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work/case-001"),
+        )
+
+        result = executor.run(
+            tool_name="vol3.windows.pslist",
+            args={"memory_image": "/evidence/mem.raw"},
+        )
+
+        assert isinstance(result, ToolOutput)
+        assert result.tool_name == "vol3.windows.pslist"
+
+    def test_dispatches_to_correct_wrapper_among_multiple(self) -> None:
+        """run() selects the wrapper matching tool_name when multiple are registered."""
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist(), _FakeVol3Psscan()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work/case-001"),
+        )
+
+        result_pslist = executor.run(
+            tool_name="vol3.windows.pslist",
+            args={"memory_image": "/evidence/mem.raw"},
+        )
+        result_psscan = executor.run(
+            tool_name="vol3.windows.psscan",
+            args={"memory_image": "/evidence/mem.raw"},
+        )
+
+        assert result_pslist.tool_name == "vol3.windows.pslist"
+        assert result_psscan.tool_name == "vol3.windows.psscan"
+
+    def test_raises_unknown_tool_error_for_unregistered_tool(self) -> None:
+        """run() raises UnknownToolError for tools not registered with the executor."""
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work/case-001"),
+        )
+
+        with pytest.raises(UnknownToolError) as exc_info:
+            executor.run(
+                tool_name="vol3.windows.svcscan",
+                args={},
+            )
+
+        assert "vol3.windows.svcscan" in str(exc_info.value)
+
+    def test_unknown_tool_error_names_available_tools(self) -> None:
+        """UnknownToolError message includes the list of registered tools."""
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist(), _FakeVol3Psscan()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work/case-001"),
+        )
+
+        with pytest.raises(UnknownToolError) as exc_info:
+            executor.run(tool_name="nonexistent.tool", args={})
+
+        error_msg = str(exc_info.value)
+        assert "vol3.windows.pslist" in error_msg or "vol3.windows.psscan" in error_msg
+
+
+class TestToolExecutorToolOutput:
+    """ToolExecutor.run() returns a correctly-formed ToolOutput."""
+
+    def test_result_has_tool_name(self) -> None:
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work"),
+        )
+        result = executor.run(
+            tool_name="vol3.windows.pslist",
+            args={"memory_image": "/evidence/mem.raw"},
+        )
+        assert result.tool_name == "vol3.windows.pslist"
+
+    def test_result_has_tool_version(self) -> None:
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work"),
+        )
+        result = executor.run(
+            tool_name="vol3.windows.pslist",
+            args={"memory_image": "/evidence/mem.raw"},
+        )
+        assert result.tool_version == "vol3 2.10.0"
+
+    def test_result_has_valid_invocation_hash(self) -> None:
+        """ToolOutput.invocation_hash passes the ToolOutput model validator."""
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work"),
+        )
+        result = executor.run(
+            tool_name="vol3.windows.pslist",
+            args={"memory_image": "/evidence/mem.raw"},
+        )
+        # The model validator in ToolOutput already verified the hash at
+        # construction; if we get here without ValidationError the hash is valid.
+        assert len(result.invocation_hash) == 64  # blake3 hex digest
+
+    def test_result_has_parsed_artifacts_list(self) -> None:
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work"),
+        )
+        result = executor.run(
+            tool_name="vol3.windows.pslist",
+            args={"memory_image": "/evidence/mem.raw"},
+        )
+        assert isinstance(result.parsed_artifacts, list)
+        assert len(result.parsed_artifacts) >= 1
+        assert result.parsed_artifacts[0].artifact_type == "process"
+
+    def test_result_has_stdout_sha256(self) -> None:
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work"),
+        )
+        result = executor.run(
+            tool_name="vol3.windows.pslist",
+            args={"memory_image": "/evidence/mem.raw"},
+        )
+        assert isinstance(result.stdout_sha256, str)
+        assert len(result.stdout_sha256) == 64  # sha256 hex
+
+
+class TestToolExecutorNotImplemented:
+    """Wrappers that raise NotImplementedError propagate the error (W2.B not landed)."""
+
+    def test_propagates_not_implemented_from_execute(self) -> None:
+        executor = ToolExecutor(
+            wrappers=[_NotImplementedWrapper()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work"),
+        )
+
+        with pytest.raises(NotImplementedError, match="W2.B"):
+            executor.run(
+                tool_name="vol3.windows.malfind",
+                args={"memory_image": "/evidence/mem.raw"},
+            )
+
+
+class TestToolExecutorRegistration:
+    """ToolExecutor registration mechanics."""
+
+    def test_empty_wrappers_list_accepted(self) -> None:
+        """Zero registered wrappers is valid at construction time."""
+        executor = ToolExecutor(
+            wrappers=[],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work"),
+        )
+        assert executor is not None
+
+    def test_duplicate_tool_name_raises_on_construction(self) -> None:
+        """Registering two wrappers with the same tool_name raises ValueError."""
+        with pytest.raises(ValueError, match="duplicate"):
+            ToolExecutor(
+                wrappers=[_FakeVol3Pslist(), _FakeVol3Pslist()],
+                evidence_path=Path("/evidence/mem.raw"),
+                work_dir=Path("/work"),
+            )
+
+    def test_registered_tool_names_property(self) -> None:
+        """ToolExecutor.registered_tool_names returns all registered tool names."""
+        executor = ToolExecutor(
+            wrappers=[_FakeVol3Pslist(), _FakeVol3Psscan()],
+            evidence_path=Path("/evidence/mem.raw"),
+            work_dir=Path("/work"),
+        )
+        names = executor.registered_tool_names
+        assert "vol3.windows.pslist" in names
+        assert "vol3.windows.psscan" in names