Prepare test harness for Orca 50 rebase

tests/conftest.py

@@ -1,8 +1,12 @@
 import importlib.util
+import os
 import sys
 import types
 from pathlib import Path
 
+import pytest
+
+os.environ["GSETTINGS_BACKEND"] = "memory"
 
 REPO_ROOT = Path(__file__).resolve().parents[1]
 SRC_ROOT = REPO_ROOT / "src"
@@ -63,3 +67,27 @@ for generated_module in ("cthulhu_i18n", "cthulhu_platform"):
     loaded_module = _load_generated_module(generated_module)
     sys.modules[f"cthulhu.{generated_module}"] = loaded_module
     setattr(cthulhu, generated_module, loaded_module)
+
+
+from cthulhu_test_fixtures import test_context  # noqa: E402,F401
+
+
+def clean_all_cthulhu_modules() -> None:
+    modules_to_remove = [
+        module_name
+        for module_name in sys.modules
+        if module_name.startswith("cthulhu.")
+        and module_name not in {"cthulhu.cthulhu_i18n", "cthulhu.cthulhu_platform"}
+    ]
+    for module_name in modules_to_remove:
+        sys.modules.pop(module_name, None)
+
+
+def pytest_configure(config: pytest.Config) -> None:
+    config.addinivalue_line("markers", "unit: marks tests as unit tests")
+
+
+def pytest_runtest_setup(item: pytest.Item) -> None:
+    clean_all_cthulhu_modules()
+    if str(SRC_ROOT) not in sys.path:
+        sys.path.insert(0, str(SRC_ROOT))