Merge remote-tracking branch 'origin/main' into fix/snapshot-viewer-gating

# Conflicts:
#	src/display_manager.py

src/display_controller.py

@@ -2125,23 +2125,10 @@ class DisplayController:
 
                     # For plugins, call display multiple times to allow game rotation
                     if manager_to_display and hasattr(manager_to_display, 'display'):
-                        # High-FPS decision, in precedence order:
-                        # 1. A plugin that declares needs_high_fps knows best
-                        #    (e.g. static-image sets it False for still PNGs,
-                        #    True for animated GIFs).
-                        # 2. Back-compat: older static-image versions without
-                        #    the attribute keep the historical forced high-FPS
-                        #    (GIF support).
-                        # 3. Otherwise scrolling plugins get high FPS.
+                        # Check if plugin needs high FPS (like stock ticker)
+                        # Always enable high-FPS for static-image plugin (for GIF animation support)
                         plugin_id = getattr(manager_to_display, 'plugin_id', None)
-                        declared = getattr(manager_to_display, 'needs_high_fps', None)
-                        if declared is not None:
-                            needs_high_fps = bool(declared)
-                            logger.debug(
-                                "[DisplayController] FPS check for %s (plugin=%s) - "
-                                "plugin declares needs_high_fps=%s",
-                                active_mode, plugin_id, needs_high_fps)
-                        elif plugin_id == 'static-image':
+                        if plugin_id == 'static-image':
                             needs_high_fps = True
                             logger.debug("FPS check - static-image plugin: forcing high-FPS mode for GIF support")
                         else:

src/display_manager.py

@@ -33,7 +33,6 @@ else:
 from contextlib import contextmanager
 from pathlib import Path
 from PIL import Image, ImageDraw, ImageFont
-import threading
 import time
 from collections import OrderedDict
 from typing import Dict, Any, List, Optional, Tuple
@@ -220,17 +219,6 @@ class DisplayManager:
         # but is never silent: the snapshot's mtime doubles as the web UI's
         # hardware-liveness signal, so a quiet failure makes health checks lie.
         self._snapshot_fail_log_ts = 0.0
-        # Dirty tracking: (image digest, brightness) of the last frame pushed
-        # to the panel; update_display() skips identical pushes. Kill switch:
-        # display.dirty_tracking: false.
-        self._dirty_tracking_enabled = bool(
-            self.config.get('display', {}).get('dirty_tracking', True))
-        self._last_pushed_digest = None
-        # Serializes update_display(): plugins can call it directly from
-        # background threads (see docstring on update_display), not just the
-        # render loop. RLock in case a caller within the critical section
-        # ever re-enters (e.g. via a nested draw callback).
-        self._update_lock = threading.RLock()
         
         # Scrolling state tracking for graceful updates
         self._scrolling_state = {
@@ -461,10 +449,6 @@ class DisplayManager:
         try:
             # RGBMatrix accepts brightness as a property
             self.matrix.brightness = brightness
-            # Brightness applies on the next swap — force a re-push even if
-            # the image itself is unchanged (belt-and-braces: brightness is
-            # also part of the dirty-tracking digest when readable).
-            self._last_pushed_digest = None
             logger.info(f"[BRIGHTNESS] Display brightness set to {brightness}%")
             return True
         except AttributeError as e:
@@ -556,70 +540,33 @@ class DisplayManager:
         return phys
 
     def update_display(self):
-        """Update the display using double buffering with proper sync.
-
-        Skips the panel push entirely when the frame is byte-identical to
-        the last pushed one (same image digest AND same brightness) — static
-        content re-rendered every second, and 125 fps loops between actual
-        scroll steps, otherwise re-walk the full framebuffer for nothing.
-        The panel keeps refreshing the current frame from its own thread,
-        so skipping a swap never blanks or freezes the hardware.
-
-        Correctness hinges on invalidation: clear() resets the digest (it
-        writes to the matrix directly), and brightness is PART of the digest
-        so a dim-schedule change is never skipped. Disable via config
-        ``display.dirty_tracking: false`` if a redraw issue is ever suspected.
-
-        Serialized via ``_update_lock``: plugins can call this directly from
-        background threads (e.g. sports base classes push an immediate
-        "live" refresh from inside update()), so without a lock two callers
-        could both pass the digest check before either writes it back,
-        double-pushing a frame, or interleave the offscreen/current canvas
-        swap below. The lock is scoped to this method, so callers never
-        need to know about it.
-        """
+        """Update the display using double buffering with proper sync."""
         try:
-            with self._update_lock:
-                if self.matrix is None:
-                    # Fallback mode - no actual hardware to update
-                    logger.debug("Update display called in fallback mode (no hardware)")
-                    # Still write a snapshot so the web UI can preview
-                    self._write_snapshot_if_due()
-                    return
-
-                if self._capture_mode_active:
-                    return  # Skip hardware write — content is being captured off-screen
-
-                digest = None
-                if self._dirty_tracking_enabled:
-                    try:
-                        brightness = getattr(self.matrix, 'brightness', None)
-                    except AttributeError:
-                        brightness = None
-                    digest = (zlib.adler32(self.image.tobytes()), brightness)
-                    if digest == self._last_pushed_digest:
-                        # Nothing changed since the last push — the panel is
-                        # already showing exactly this frame.
-                        self._write_snapshot_if_due()
-                        return
-
-                # Copy the current image to the offscreen canvas. In double-sided
-                # mode the logical screen is first tiled across the full chain.
-                if self._double_sided is not None:
-                    self.offscreen_canvas.SetImage(self._composite_double_sided())
-                else:
-                    self.offscreen_canvas.SetImage(self.image)
-
-                # Swap buffers immediately
-                self.matrix.SwapOnVSync(self.offscreen_canvas)
-
-                # Swap our canvas references
-                self.offscreen_canvas, self.current_canvas = self.current_canvas, self.offscreen_canvas
-
-                self._last_pushed_digest = digest
-
-                # Write a snapshot for the web preview (throttled)
+            if self.matrix is None:
+                # Fallback mode - no actual hardware to update
+                logger.debug("Update display called in fallback mode (no hardware)")
+                # Still write a snapshot so the web UI can preview
                 self._write_snapshot_if_due()
+                return
+
+            if self._capture_mode_active:
+                return  # Skip hardware write — content is being captured off-screen
+
+            # Copy the current image to the offscreen canvas. In double-sided
+            # mode the logical screen is first tiled across the full chain.
+            if self._double_sided is not None:
+                self.offscreen_canvas.SetImage(self._composite_double_sided())
+            else:
+                self.offscreen_canvas.SetImage(self.image)
+
+            # Swap buffers immediately
+            self.matrix.SwapOnVSync(self.offscreen_canvas)
+            
+            # Swap our canvas references
+            self.offscreen_canvas, self.current_canvas = self.current_canvas, self.offscreen_canvas
+
+            # Write a snapshot for the web preview (throttled)
+            self._write_snapshot_if_due()
         except Exception as e:
             logger.error(f"Error updating display: {e}")
 
@@ -653,9 +600,6 @@ class DisplayManager:
                 # Clear both canvases and the underlying matrix to ensure no artifacts.
                 # Failures are non-fatal — the image buffer is already black above, so
                 # the next update_display() call will push clean content regardless.
-                # The matrix content no longer matches the last pushed digest,
-                # so dirty tracking must not skip the next push.
-                self._last_pushed_digest = None
                 try:
                     self.offscreen_canvas.Clear()
                 except (RuntimeError, OSError) as e:

src/plugin_system/store_manager.py

@@ -142,28 +142,9 @@ class PluginStoreManager:
         # then get the result from the warm cache (double-checked locking).
         self._registry_fetch_lock = threading.Lock()
 
-        # Per-plugin locks for _reinstall_with_rollback: the web UI runs
-        # Flask with threaded=True, so two overlapping requests for the
-        # same plugin_id (double-click, two browser tabs) would otherwise
-        # both rename the same directory aside — one succeeds, and the
-        # loser can end up renaming the winner's in-progress install aside
-        # mid-download, stealing its own rollback safety net. Keyed by
-        # plugin_id so unrelated plugins still update concurrently.
-        self._reinstall_locks: Dict[str, threading.Lock] = {}
-        self._reinstall_locks_guard = threading.Lock()
-
         # Ensure plugins directory exists
         self.plugins_dir.mkdir(exist_ok=True)
 
-    def _get_reinstall_lock(self, plugin_id: str) -> threading.Lock:
-        """Lazily create (or fetch) the per-plugin reinstall lock."""
-        with self._reinstall_locks_guard:
-            lock = self._reinstall_locks.get(plugin_id)
-            if lock is None:
-                lock = threading.Lock()
-                self._reinstall_locks[plugin_id] = lock
-            return lock
-
     def _record_cache_backoff(self, cache_dict: Dict, cache_key: str,
                               cache_timeout: int, payload: Any) -> None:
         """Bump a cache entry's timestamp so subsequent lookups hit the
@@ -2282,74 +2263,6 @@ class PluginStoreManager:
             self.logger.error(f"Error uninstalling plugin {plugin_id}: {e}")
             return False
     
-    def _reinstall_with_rollback(self, plugin_id: str, plugin_path: Path) -> bool:
-        """Replace an installed plugin with a fresh install, atomically.
-
-        The old install is renamed aside (not deleted) until the new install
-        succeeds, then removed; on ANY install failure the old directory is
-        restored. This is the difference between a failed update and a
-        destroyed plugin: the previous delete-then-install flow permanently
-        removed plugins whenever the download failed mid-update (seen in the
-        field during the monorepo migration on a Pi with broken DNS — every
-        old-remote plugin was deleted and none could be re-downloaded).
-
-        The aside name embeds '.standalone-backup-' so plugin discovery
-        (plugin_manager._scan_directory_for_plugins) ignores it even though
-        it still contains a manifest.json.
-
-        Held for the whole operation under a per-plugin_id lock: two
-        overlapping requests for the same plugin (double-click, two
-        browser tabs — the web UI runs Flask with threaded=True) must not
-        interleave their renames, or the second could steal the first's
-        rollback safety net mid-install. Other plugin_ids are unaffected.
-        """
-        with self._get_reinstall_lock(plugin_id):
-            backup_path = plugin_path.with_name(
-                f"{plugin_path.name}.standalone-backup-migrating")
-            # A stale aside from a previous crash would block the rename
-            if backup_path.exists():
-                if not self._safe_remove_directory(backup_path):
-                    self.logger.error(
-                        f"Could not clear stale backup for {plugin_id} at "
-                        f"{backup_path}; leaving old install in place")
-                    return False
-            try:
-                plugin_path.rename(backup_path)
-            except OSError as e:
-                self.logger.error(
-                    f"Could not set aside old plugin directory for {plugin_id}: {e}")
-                return False
-
-            try:
-                installed = self.install_plugin(plugin_id)
-            except Exception as e:
-                self.logger.error(f"Reinstall of {plugin_id} raised: {e}")
-                installed = False
-
-            if installed:
-                if not self._safe_remove_directory(backup_path):
-                    self.logger.warning(
-                        f"Update of {plugin_id} succeeded but the old backup "
-                        f"at {backup_path} could not be removed; it will be "
-                        f"cleared on the next update")
-                return True
-
-            # Install failed (bad network, registry error...) — put the old
-            # version back so the user still has a working plugin.
-            self.logger.error(
-                f"Reinstall of {plugin_id} failed; restoring previous version")
-            try:
-                if plugin_path.exists():
-                    # partial download debris from the failed install
-                    self._safe_remove_directory(plugin_path)
-                backup_path.rename(plugin_path)
-                self.logger.info(f"Restored previous install of {plugin_id}")
-            except OSError as e:
-                self.logger.error(
-                    f"CRITICAL: could not restore {plugin_id} from {backup_path}: {e}. "
-                    f"The previous install is preserved there — rename it back manually.")
-            return False
-
     def update_plugin(self, plugin_id: str) -> bool:
         """
         Update a plugin to the latest commit on its upstream branch.
@@ -2412,7 +2325,10 @@ class PluginStoreManager:
                             f"Plugin {resolved_id} git remote ({local_remote}) differs from registry ({registry_repo}). "
                             f"Reinstalling from registry to migrate to new source."
                         )
-                        return self._reinstall_with_rollback(resolved_id, plugin_path)
+                        if not self._safe_remove_directory(plugin_path):
+                            self.logger.error(f"Failed to remove old plugin directory for {resolved_id}")
+                            return False
+                        return self.install_plugin(resolved_id)
 
                     # Check if already up to date
                     if remote_sha and local_sha and remote_sha.startswith(local_sha):
@@ -2716,11 +2632,11 @@ class PluginStoreManager:
             # Plugin is not a git repo but is in registry and has a newer version - reinstall
             self.logger.info(f"Plugin {plugin_id} not installed via git; re-installing latest archive (registry id: {registry_id})")
 
-            # Reinstall with the old version kept aside until the new
-            # download succeeds — this is the path every routine store
-            # update takes, and a mid-update network failure must not
-            # destroy the user's plugin.
-            return self._reinstall_with_rollback(registry_id, plugin_path)
+            # Remove directory and reinstall fresh
+            if not self._safe_remove_directory(plugin_path):
+                self.logger.error(f"Failed to remove old plugin directory for {plugin_id}")
+                return False
+            return self.install_plugin(registry_id)
 
         except Exception as e:
             import traceback

test/test_display_dirty_tracking.py

@@ -1,162 +0,0 @@
-"""Tests for update_display dirty tracking (src/display_manager.py).
-
-Runs against RGBMatrixEmulator (EMULATOR=true), exercising the REAL
-DisplayManager — not a mock — so the skip logic, its invalidation hooks,
-and the kill switch are verified off-Pi.
-
-The invariants:
-- identical frames are pushed exactly once (SwapOnVSync not re-called)
-- ANY pixel change pushes
-- clear() and set_brightness() invalidate (the two paths that alter panel
-  state outside the digest's view)
-- the kill switch (display.dirty_tracking: false) restores always-push
-"""
-
-import os
-import sys
-import time
-
-os.environ["EMULATOR"] = "true"
-
-import pytest
-
-sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
-
-
-@pytest.fixture(scope="module")
-def dm():
-    """One real DisplayManager on the emulator (it's a process singleton)."""
-    from src.display_manager import DisplayManager
-    DisplayManager._instance = None
-    DisplayManager._initialized = False
-    manager = DisplayManager({
-        "display": {
-            "hardware": {"rows": 32, "cols": 64, "chain_length": 2,
-                         "parallel": 1, "brightness": 90},
-            "runtime": {"gpio_slowdown": 0},
-        },
-    }, suppress_test_pattern=True)
-    yield manager
-    DisplayManager._instance = None
-    DisplayManager._initialized = False
-
-
-class _SwapSpy:
-    """Counts SwapOnVSync calls through the real matrix object."""
-
-    def __init__(self, matrix):
-        self.matrix = matrix
-        self.count = 0
-        self._orig = matrix.SwapOnVSync
-
-    def __enter__(self):
-        def counting(canvas):
-            self.count += 1
-            return self._orig(canvas)
-        self.matrix.SwapOnVSync = counting
-        return self
-
-    def __exit__(self, *exc):
-        self.matrix.SwapOnVSync = self._orig
-
-
-class TestDirtyTracking:
-    def test_identical_frames_push_once(self, dm):
-        dm.draw.rectangle([0, 0, 10, 10], fill=(255, 0, 0))
-        with _SwapSpy(dm.matrix) as spy:
-            dm.update_display()
-            dm.update_display()
-            dm.update_display()
-        assert spy.count == 1
-
-    def test_pixel_change_pushes(self, dm):
-        dm.update_display()
-        with _SwapSpy(dm.matrix) as spy:
-            dm.draw.point((5, 5), fill=(0, 255, 0))
-            dm.update_display()
-            dm.update_display()  # unchanged again
-        assert spy.count == 1
-
-    def test_clear_invalidates(self, dm):
-        dm.draw.rectangle([0, 0, 20, 20], fill=(0, 0, 255))
-        dm.update_display()
-        dm.clear()  # writes to the matrix directly; digest must reset
-        with _SwapSpy(dm.matrix) as spy:
-            dm.update_display()  # black frame after clear must still push
-        assert spy.count == 1
-
-    def test_brightness_change_forces_push(self, dm):
-        dm.draw.rectangle([0, 0, 20, 20], fill=(200, 200, 200))
-        dm.update_display()
-        with _SwapSpy(dm.matrix) as spy:
-            dm.update_display()          # identical -> skipped
-            assert spy.count == 0
-            dm.set_brightness(40)        # dim schedule scenario
-            dm.update_display()          # same image, new brightness -> push
-        assert spy.count == 1
-        dm.set_brightness(90)
-
-    def test_snapshot_still_written_on_skip(self, dm, tmp_path):
-        """The web preview mirror must keep working through skipped panel
-        pushes: _write_snapshot_if_due() still runs on the dirty-tracking
-        skip path and applies its own write/touch policy rather than being
-        bypassed entirely (see src/common/snapshot_policy.py — an unchanged
-        frame is touched, not re-encoded, once TOUCH_INTERVAL elapses)."""
-        dm._snapshot_path = str(tmp_path / "snap.png")
-        dm._last_snapshot_ts = 0.0
-        dm._last_snapshot_touch_ts = 0.0
-        dm._last_snapshot_digest = None
-        dm.draw.rectangle([0, 0, 30, 8], fill=(255, 255, 0))
-        dm.update_display()   # push + snapshot write (first frame)
-        assert os.path.exists(dm._snapshot_path)
-        first_mtime = os.path.getmtime(dm._snapshot_path)
-
-        # Age the write/touch bookkeeping past TOUCH_INTERVAL so the next
-        # identical frame is due for a touch, then push it again: dirty
-        # tracking must skip the panel write, but the snapshot mirror must
-        # still get its mtime bumped so the health check doesn't go stale.
-        from src.common import snapshot_policy
-        stale_ts = time.time() - snapshot_policy.TOUCH_INTERVAL - 1.0
-        dm._last_snapshot_ts = stale_ts
-        dm._last_snapshot_touch_ts = stale_ts
-        with _SwapSpy(dm.matrix) as spy:
-            dm.update_display()  # identical frame -> panel push skipped
-        assert spy.count == 0
-        assert os.path.getmtime(dm._snapshot_path) > first_mtime
-
-
-class TestKillSwitch:
-    def test_dirty_tracking_can_be_disabled(self, dm):
-        dm._dirty_tracking_enabled = False
-        try:
-            dm.draw.rectangle([0, 0, 10, 10], fill=(1, 2, 3))
-            with _SwapSpy(dm.matrix) as spy:
-                dm.update_display()
-                dm.update_display()
-                dm.update_display()
-            assert spy.count == 3  # always-push, exactly the old behavior
-        finally:
-            dm._dirty_tracking_enabled = True
-            dm._last_pushed_digest = None
-
-    def test_config_flag_wires_through(self):
-        from src.display_manager import DisplayManager
-        DisplayManager._instance = None
-        DisplayManager._initialized = False
-        try:
-            manager = DisplayManager({
-                "display": {
-                    "hardware": {"rows": 32, "cols": 64, "chain_length": 1,
-                                 "parallel": 1},
-                    "runtime": {"gpio_slowdown": 0},
-                    "dirty_tracking": False,
-                },
-            }, suppress_test_pattern=True)
-            assert manager._dirty_tracking_enabled is False
-        finally:
-            DisplayManager._instance = None
-            DisplayManager._initialized = False
-
-
-if __name__ == "__main__":
-    sys.exit(pytest.main([__file__, "-v"]))

test/test_store_update_rollback.py

@@ -1,171 +0,0 @@
-"""Tests for atomic plugin updates (store_manager._reinstall_with_rollback).
-
-Regression for a field data-loss incident: update_plugin's reinstall paths
-(monorepo migration AND routine archive updates) deleted the installed
-plugin BEFORE downloading its replacement — a mid-update network failure
-permanently destroyed the plugin. Seen live: a Pi with broken DNS lost 12
-plugins from one update pass.
-"""
-
-import json
-import os
-import sys
-import threading
-import time
-from pathlib import Path
-from unittest.mock import patch
-
-import pytest
-
-sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
-
-from src.plugin_system.store_manager import PluginStoreManager  # noqa: E402
-
-PLUGIN_ID = "rollback-test-plugin"
-
-
-@pytest.fixture
-def store(tmp_path):
-    mgr = PluginStoreManager(plugins_dir=str(tmp_path))
-    plugin_dir = tmp_path / PLUGIN_ID
-    plugin_dir.mkdir()
-    (plugin_dir / "manifest.json").write_text(json.dumps(
-        {"id": PLUGIN_ID, "name": "Rollback Test", "version": "1.0.0"}))
-    (plugin_dir / "manager.py").write_text("# old version marker\n")
-    return mgr, plugin_dir
-
-
-class TestReinstallWithRollback:
-    def test_failed_install_restores_old_version(self, store):
-        """The whole point: a failed download must leave the old install."""
-        mgr, plugin_dir = store
-        with patch.object(mgr, "install_plugin", return_value=False):
-            ok = mgr._reinstall_with_rollback(PLUGIN_ID, plugin_dir)
-        assert ok is False
-        assert plugin_dir.exists()
-        assert "old version marker" in (plugin_dir / "manager.py").read_text()
-        # no aside debris left behind
-        leftovers = [p for p in plugin_dir.parent.iterdir()
-                     if "standalone-backup" in p.name]
-        assert leftovers == []
-
-    def test_install_exception_restores_old_version(self, store):
-        mgr, plugin_dir = store
-        with patch.object(mgr, "install_plugin",
-                          side_effect=RuntimeError("network down")):
-            ok = mgr._reinstall_with_rollback(PLUGIN_ID, plugin_dir)
-        assert ok is False
-        assert plugin_dir.exists()
-        assert "old version marker" in (plugin_dir / "manager.py").read_text()
-
-    def test_successful_install_removes_aside(self, store):
-        mgr, plugin_dir = store
-
-        def fake_install(plugin_id):
-            new_dir = plugin_dir  # same path, new content
-            new_dir.mkdir(exist_ok=True)
-            (new_dir / "manager.py").write_text("# new version\n")
-            (new_dir / "manifest.json").write_text(json.dumps(
-                {"id": PLUGIN_ID, "name": "Rollback Test", "version": "2.0.0"}))
-            return True
-
-        with patch.object(mgr, "install_plugin", side_effect=fake_install):
-            ok = mgr._reinstall_with_rollback(PLUGIN_ID, plugin_dir)
-        assert ok is True
-        assert "new version" in (plugin_dir / "manager.py").read_text()
-        leftovers = [p for p in plugin_dir.parent.iterdir()
-                     if "standalone-backup" in p.name]
-        assert leftovers == []
-
-    def test_partial_download_debris_is_replaced_by_old_version(self, store):
-        """A failed install that left a partial directory must still roll back."""
-        mgr, plugin_dir = store
-
-        def fake_partial_install(plugin_id):
-            plugin_dir.mkdir(exist_ok=True)
-            (plugin_dir / "half-downloaded.tmp").write_text("junk")
-            return False
-
-        with patch.object(mgr, "install_plugin", side_effect=fake_partial_install):
-            ok = mgr._reinstall_with_rollback(PLUGIN_ID, plugin_dir)
-        assert ok is False
-        assert "old version marker" in (plugin_dir / "manager.py").read_text()
-        assert not (plugin_dir / "half-downloaded.tmp").exists()
-
-    def test_stale_aside_from_previous_crash_is_cleared(self, store):
-        mgr, plugin_dir = store
-        stale = plugin_dir.parent / f"{PLUGIN_ID}.standalone-backup-migrating"
-        stale.mkdir()
-        (stale / "old.txt").write_text("stale")
-        with patch.object(mgr, "install_plugin", return_value=False) as mock_install:
-            ok = mgr._reinstall_with_rollback(PLUGIN_ID, plugin_dir)
-        # The reinstall itself still fails (mocked) and the old install is
-        # restored, but the stale aside must not have survived — otherwise
-        # it would have blocked this run's own rename (or a future one).
-        assert not stale.exists()
-        mock_install.assert_called_once_with(PLUGIN_ID)
-        assert ok is False
-        assert plugin_dir.exists()
-        assert "old version marker" in (plugin_dir / "manager.py").read_text()
-
-    def test_concurrent_updates_for_same_plugin_are_serialized(self, store):
-        """Two overlapping requests for the same plugin_id (double-click,
-        two browser tabs — the web UI runs Flask with threaded=True) must
-        not interleave: the loser must wait for the winner to finish
-        rather than renaming the winner's in-progress install aside and
-        stealing its rollback safety net."""
-        mgr, plugin_dir = store
-
-        active = 0
-        max_active = 0
-        guard = threading.Lock()
-
-        def fake_install(plugin_id):
-            nonlocal active, max_active
-            with guard:
-                active += 1
-                max_active = max(max_active, active)
-            time.sleep(0.05)
-            plugin_dir.mkdir(exist_ok=True)
-            (plugin_dir / "manager.py").write_text("# new version\n")
-            (plugin_dir / "manifest.json").write_text(json.dumps(
-                {"id": PLUGIN_ID, "name": "Rollback Test", "version": "2.0.0"}))
-            with guard:
-                active -= 1
-            return True
-
-        results = []
-
-        def worker():
-            results.append(mgr._reinstall_with_rollback(PLUGIN_ID, plugin_dir))
-
-        with patch.object(mgr, "install_plugin", side_effect=fake_install):
-            threads = [threading.Thread(target=worker) for _ in range(2)]
-            for t in threads:
-                t.start()
-            for t in threads:
-                t.join(timeout=5)
-
-        assert max_active == 1, "install_plugin ran concurrently for the same plugin_id"
-        assert results == [True, True]
-        assert plugin_dir.exists()
-        assert "new version" in (plugin_dir / "manager.py").read_text()
-        leftovers = [p for p in plugin_dir.parent.iterdir()
-                     if "standalone-backup" in p.name]
-        assert leftovers == []
-
-    def test_aside_name_is_invisible_to_discovery(self, store, tmp_path):
-        """The aside still contains a manifest.json — discovery must skip it
-        (relies on the existing '.standalone-backup-' exclusion)."""
-        mgr, plugin_dir = store
-        from src.plugin_system.plugin_manager import PluginManager
-        aside = plugin_dir.parent / f"{PLUGIN_ID}.standalone-backup-migrating"
-        plugin_dir.rename(aside)
-        pm = PluginManager(plugins_dir=str(tmp_path), config_manager=None,
-                           display_manager=None, cache_manager=None)
-        found = pm._scan_directory_for_plugins(Path(tmp_path))
-        assert PLUGIN_ID not in found
-
-
-if __name__ == "__main__":
-    sys.exit(pytest.main([__file__, "-v"]))