fix(monitor): isolate offline tests and preserve localized field icons

AppImage/scripts/tests/health_fixture_modules.py

@@ -0,0 +1,60 @@
+"""Private real-module loaders for offline health fixtures.
+
+Never cache test dependencies in sys.modules. Persistence uses its real global
+constructor and SQLite schema, redirected to the caller's temporary directory.
+Monitor methods are unmodified; only unrelated import-time host dependencies and
+singleton cleanup are bounded. Runtime/deferred dependencies belong in each
+calling test's patch.dict context, not in the process-wide module cache.
+"""
+import contextlib
+import importlib.util
+import io
+from pathlib import Path
+import sys
+from types import ModuleType, SimpleNamespace
+from unittest.mock import patch
+
+
+SCRIPTS = Path(__file__).resolve().parents[1]
+# Keep Path usable while the constructor's imported pathlib.Path is redirected.
+ConcretePath = type(Path())
+
+
+def load_source(name):
+    spec = importlib.util.spec_from_file_location('fixture_' + name, SCRIPTS / (name + '.py'))
+    assert spec is not None and spec.loader is not None
+    module = importlib.util.module_from_spec(spec)
+    with patch.object(sys, 'dont_write_bytecode', True):
+        spec.loader.exec_module(module)
+    return module
+
+
+def load_health_persistence(data_dir):
+    def fixture_path(*args, **kwargs):
+        if args == ('/usr/local/share/proxmenux',):
+            return ConcretePath(data_dir)
+        return ConcretePath(*args, **kwargs)
+
+    with patch('pathlib.Path', fixture_path), contextlib.redirect_stdout(io.StringIO()):
+        return load_source('health_persistence')
+
+
+def load_health_modules(data_dir):
+    persistence = load_health_persistence(data_dir)
+    # These import-only dependencies are not exercised by these unit tests.
+    # Real methods and the real monitor singleton still execute from source.
+    dependencies = {
+        'health_persistence': persistence,
+        'psutil': ModuleType('psutil'),
+        'proxmox_storage_monitor': SimpleNamespace(proxmox_storage_monitor=SimpleNamespace()),
+        'pbs_manager': SimpleNamespace(get_platform=lambda: {'product': 'pve'}, PBS_SERVICES=()),
+        'startup_grace': ModuleType('startup_grace'),
+    }
+    with patch.dict(sys.modules, dependencies), \
+            patch.object(persistence.health_persistence, 'cleanup_old_errors'), \
+            patch('os.path.exists', return_value=False):
+        monitor = load_source('health_monitor')
+        events = load_source('notification_events')
+    thresholds = load_source('health_thresholds')
+    setattr(thresholds, '_CONFIG_PATH', str(ConcretePath(data_dir) / 'health_thresholds.json'))
+    return monitor, events, thresholds