Add FIT persistency scenarios: supported datatypes

feature_integration_tests/test_cases/BUILD

@@ -46,6 +46,7 @@ score_py_pytest(
     data = [
         "conftest.py",
         "fit_scenario.py",
+        "persistency_scenario.py",
         "test_properties.py",
         "//feature_integration_tests/test_scenarios/rust:rust_test_scenarios",
     ],
@@ -67,6 +68,7 @@ score_py_pytest(
     data = [
         "conftest.py",
         "fit_scenario.py",
+        "persistency_scenario.py",
         "test_properties.py",
         "//feature_integration_tests/test_scenarios/cpp:cpp_test_scenarios",
     ],

feature_integration_tests/test_cases/fit_scenario.py

@@ -11,8 +11,8 @@
 # SPDX-License-Identifier: Apache-2.0
 # *******************************************************************************
 import shutil
-from collections.abc import Generator
 from pathlib import Path
+from typing import Generator
 
 import pytest
 from testing_utils import (
@@ -64,7 +64,7 @@ def temp_dir_common(
 
 class FitScenario(Scenario):
     """
-    CIT test scenario definition.
+    FIT test scenario definition.
     """
 
     @pytest.fixture(scope="class")
@@ -90,10 +90,9 @@ def results(
     ) -> ScenarioResult:
         result = self._run_command(command, execution_timeout, args, kwargs)
         success = result.return_code == ResultCode.SUCCESS and not result.hang
-        expect_failure = self.expect_command_failure()
-        if expect_failure and success:
+        if self.expect_command_failure() and success:
             raise RuntimeError(f"Command execution succeeded unexpectedly: {result=}")
-        if not expect_failure and not success:
+        if not self.expect_command_failure() and not success:
             raise RuntimeError(f"Command execution failed unexpectedly: {result=}")
         return result
 

feature_integration_tests/test_cases/persistency_scenario.py

@@ -0,0 +1,150 @@
+# *******************************************************************************
+# Copyright (c) 2026 Contributors to the Eclipse Foundation
+#
+# See the NOTICE file(s) distributed with this work for additional
+# information regarding copyright ownership.
+#
+# This program and the accompanying materials are made available under the
+# terms of the Apache License Version 2.0 which is available at
+# https://www.apache.org/licenses/LICENSE-2.0
+#
+# SPDX-License-Identifier: Apache-2.0
+# *******************************************************************************
+"""
+Helpers and base scenario class for persistency feature integration tests.
+
+``create_kvs_defaults_file`` and ``read_kvs_snapshot`` provide the file-system
+operations that test methods use to set up and inspect KVS state.
+``PersistencyScenario`` is a :class:`FitScenario` subclass that supplies the
+shared ``temp_dir`` fixture so individual test classes do not have to duplicate it.
+"""
+
+import json
+from collections.abc import Generator
+from pathlib import Path
+from zlib import adler32
+
+import pytest
+from fit_scenario import FitScenario, temp_dir_common
+
+
+def create_kvs_defaults_file(dir_path: Path, instance_id: int, values: dict) -> Path:
+    """
+    Create a KVS defaults JSON file and matching hash file at conventional paths.
+
+    KVS expects defaults at: {dir}/kvs_{instance_id}_default.json
+    and the hash at:         {dir}/kvs_{instance_id}_default.hash
+
+    The JSON format is: {"key": {"t": "type_tag", "v": value}, ...}
+    The hash is adler32 of the JSON string, written as 4 big-endian bytes.
+
+    Parameters
+    ----------
+    dir_path : Path
+        Working directory for the KVS instance.
+    instance_id : int
+        KVS instance identifier.
+    values : dict
+        Mapping of key -> (type_tag, value), e.g. {"my_key": ("f64", 1.0)}.
+
+    Returns
+    -------
+    Path
+        Path to the created JSON defaults file.
+    """
+    json_path = dir_path / f"kvs_{instance_id}_default.json"
+    hash_path = dir_path / f"kvs_{instance_id}_default.hash"
+
+    data = {key: {"t": type_tag, "v": val} for key, (type_tag, val) in values.items()}
+    json_str = json.dumps(data)
+
+    json_path.write_text(json_str)
+    hash_path.write_bytes(adler32(json_str.encode()).to_bytes(length=4, byteorder="big"))
+    return json_path
+
+
+def read_kvs_snapshot(dir_path: Path, instance_id: int, snapshot_id: int = 0) -> dict:
+    """
+    Read and parse the KVS snapshot JSON for a given instance.
+
+    Supports both the Rust/normalized envelope format {"t":"obj","v":{...}}
+    and the raw C++ format {key: {...}}. Returns the inner key -> tagged-value mapping.
+
+    Parameters
+    ----------
+    dir_path : Path
+        Working directory containing the KVS snapshot files.
+    instance_id : int
+        KVS instance identifier used in the filename convention.
+    snapshot_id : int, optional
+        Snapshot sequence number (default 0).
+
+    Returns
+    -------
+    dict
+        Mapping of key -> tagged-value dict, e.g. {"mykey": {"t": "f64", "v": 1.0}}.
+    """
+    path = dir_path / f"kvs_{instance_id}_{snapshot_id}.json"
+    data = json.loads(path.read_text())
+    if isinstance(data, dict) and data.get("t") == "obj" and "v" in data:
+        return data["v"]
+    return data
+
+
+def verify_kvs_snapshot_hash(dir_path: Path, instance_id: int, snapshot_id: int = 0) -> None:
+    """
+    Assert that the snapshot hash file content matches the Adler-32 of the JSON file.
+
+    After ``normalize_snapshot_file_to_rust_envelope`` rewrites the JSON, the
+    companion ``.hash`` file must also be rewritten.  This helper detects any
+    mismatch between the two, catching stale hashes introduced by manual or
+    tool-driven JSON modifications.
+
+    Parameters
+    ----------
+    dir_path : Path
+        Working directory containing the KVS snapshot files.
+    instance_id : int
+        KVS instance identifier used in the filename convention.
+    snapshot_id : int, optional
+        Snapshot sequence number (default 0).
+    """
+    json_path = dir_path / f"kvs_{instance_id}_{snapshot_id}.json"
+    hash_path = dir_path / f"kvs_{instance_id}_{snapshot_id}.hash"
+    json_bytes = json_path.read_bytes()
+    expected = adler32(json_bytes).to_bytes(4, byteorder="big")
+    actual = hash_path.read_bytes()
+    assert actual == expected, (
+        f"Hash mismatch for kvs_{instance_id}_{snapshot_id}: "
+        f"hash file contains {actual.hex()} but Adler-32 of the JSON is {expected.hex()}"
+    )
+
+
+class PersistencyScenario(FitScenario):
+    """
+    Base class for persistency feature integration tests.
+
+    Provides the ``temp_dir`` fixture shared by all persistency test classes,
+    avoiding fixture duplication across subclasses.
+    """
+
+    @pytest.fixture(scope="class")
+    def temp_dir(
+        self,
+        tmp_path_factory: pytest.TempPathFactory,
+        version: str,
+    ) -> Generator[Path, None, None]:
+        """
+        Provide a temporary working directory for the KVS instance.
+
+        The directory is named after the test class and parametrized version,
+        and is automatically removed after the test class completes.
+
+        Parameters
+        ----------
+        tmp_path_factory : pytest.TempPathFactory
+            Built-in pytest factory for temporary directories.
+        version : str
+            Parametrized scenario version (``"rust"`` or ``"cpp"``).
+        """
+        yield from temp_dir_common(tmp_path_factory, self.__class__.__name__, version)