test(disk-hygiene): mock sys.argv in run_guard* helpers to seal the kill-switch argv seam

plugins/disk-hygiene/.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://json.schemastore.org/claude-code-plugin-manifest.json",
   "name": "disk-hygiene",
-  "version": "0.4.4",
+  "version": "0.4.5",
   "description": "Context-aware disk hygiene for arbitrary directory trees: inventories orphaned and temporary artifacts, classifies evidence into review tiers, and offers exact-path cleanup only after a fresh safety preview and explicit per-tier approval. The target is read-only by default; OS-managed paths, links and mount points, VCS-tracked content, changed entries, and live-handle uncertainty fail closed.",
   "author": {
     "name": "Melodic Software",

plugins/disk-hygiene/CHANGELOG.md

@@ -3,6 +3,20 @@
 All notable changes to the `disk-hygiene` plugin are documented here. Format follows
 [Keep a Changelog](https://keepachangelog.com/en/1.1.0/); this plugin uses semantic versioning.
 
+## [0.4.5]
+
+### Changed
+
+- **Test isolation only — no runtime behavior change.** The `run_guard`, `run_guard_disabled`, and
+  `run_guard_powershell_disabled` helpers in `test_hygiene.py` mocked `os.environ` to exercise the
+  kill switch but left `sys.argv` unpatched. Since the guard reads `--disk-hygiene-enabled` from
+  `sys.argv[1:]` before the environment fallback, a test runner whose real invocation argv happened
+  to carry that flag could override the env-var mock and flip an expected `deny` to `ask`. Each
+  helper now patches `guard.sys.argv` to a clean, flag-free argv alongside its existing environment
+  mock — matching the pattern the `run_guard_enabled_argv` helper already established — so the
+  environment variable stays the sole channel under test. Standard `unittest`/`pytest` invocations
+  never produced such argv, so this seals latent fragility rather than a live failure.
+
 ## [0.4.4]
 
 ### Fixed

plugins/disk-hygiene/skills/clean/scripts/test_hygiene.py

@@ -1064,6 +1064,7 @@ def run_guard(self, command: str) -> dict[str, object]:
         with (
             mock.patch("sys.stdin", stdin),
             redirect_stdout(stdout),
+            mock.patch.object(guard.sys, "argv", [str(SCRIPT_DIR / "destructive_guard.py")]),
             mock.patch.dict(
                 "os.environ", {"CLAUDE_PLUGIN_OPTION_DISK_HYGIENE_ENABLED": "true"}, clear=False
             ),
@@ -1077,6 +1078,7 @@ def run_guard_disabled(self, command: str) -> dict[str, object]:
         with (
             mock.patch("sys.stdin", stdin),
             redirect_stdout(stdout),
+            mock.patch.object(guard.sys, "argv", [str(SCRIPT_DIR / "destructive_guard.py")]),
             mock.patch.dict(
                 "os.environ", {"CLAUDE_PLUGIN_OPTION_DISK_HYGIENE_ENABLED": "false"}, clear=False
             ),
@@ -1319,6 +1321,7 @@ def run_guard_powershell_disabled(
         with (
             mock.patch("sys.stdin", stdin),
             redirect_stdout(stdout),
+            mock.patch.object(guard.sys, "argv", [str(SCRIPT_DIR / "destructive_guard.py")]),
             mock.patch.dict(
                 "os.environ",
                 {"CLAUDE_PLUGIN_OPTION_DISK_HYGIENE_ENABLED": "false"},