fix(sync): honour readiness and suspension in Customisation Sync

(src/features/ConfigSync/CmdConfigSync.ts)
- Call the readiness predicate before accepting configuration file events.
- Stop the periodic sweep while settings are applied and let the resume lifecycle scan and restart it once.

(src/features/ConfigSync/CmdConfigSync.applySettings.unit.spec.ts)
- Exercise the ControlService settings path while active, suspended, and resumed.
- Verify that suspended settings application performs no scan and leaves the periodic sweep stopped.

(src/features/ConfigSync/CmdConfigSync.readiness.unit.spec.ts)
- Cover configuration file events before and after application readiness.

(updates.md)
- Document the readiness and suspension behaviour.

src/features/ConfigSync/CmdConfigSync.applySettings.unit.spec.ts

@@ -0,0 +1,190 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("@/deps.ts", () => ({
+    addIcon: vi.fn(),
+    diff_match_patch: class DiffMatchPatch {},
+    normalizePath: vi.fn((path: string) => path),
+    parseYaml: vi.fn(),
+    Platform: {},
+}));
+vi.mock("./PluginDialogModal.ts", () => ({
+    PluginDialogModal: class PluginDialogModal {},
+}));
+vi.mock("@/features/HiddenFileCommon/JsonResolveModal.ts", () => ({
+    JsonResolveModal: class JsonResolveModal {},
+}));
+vi.mock("@/modules/features/InteractiveConflictResolving/ConflictResolveModal.ts", () => ({
+    ConflictResolveModal: class ConflictResolveModal {},
+}));
+// The readiness and suspension helpers come from the real LiveSyncCommands, so only its log view dependency is replaced.
+vi.mock("@/modules/features/ModuleLog.ts", () => ({
+    MARK_DONE: "",
+}));
+vi.mock("@/common/types.ts", () => ({
+    ICXHeader: "ix:",
+    PERIODIC_PLUGIN_SWEEP: 60,
+}));
+vi.mock("@/common/utils.ts", () => ({
+    cancelTask: vi.fn(),
+    EVEN: Symbol("even"),
+    isCustomisationSyncMetadata: vi.fn(),
+    isPluginMetadata: vi.fn(),
+    scheduleTask: vi.fn(),
+}));
+vi.mock("@/common/PeriodicProcessor.ts", () => ({
+    PeriodicProcessor: class PeriodicProcessor {},
+}));
+vi.mock("@/common/events.ts", () => ({
+    EVENT_REQUEST_OPEN_PLUGIN_SYNC_DIALOG: "open-plugin-sync",
+    eventHub: {
+        onEvent: vi.fn(),
+    },
+}));
+vi.mock("@/common/translation", () => ({
+    $msg: vi.fn((message: string) => message),
+}));
+vi.mock("@/common/obsidianCommunityPlugins.ts", () => ({
+    getObsidianCommunityPluginManager: vi.fn(),
+}));
+
+import { createServiceContext, type ServiceContext } from "@vrtmrz/livesync-commonlib/context";
+import { ControlService } from "@vrtmrz/livesync-commonlib/compat/services/base/ControlService";
+import { InjectableAppLifecycleService } from "@vrtmrz/livesync-commonlib/compat/services/implements/injectable/InjectableAppLifecycleService";
+import { InjectableSettingService } from "@vrtmrz/livesync-commonlib/compat/services/implements/injectable/InjectableSettingService";
+import { ConfigSync } from "./CmdConfigSync";
+
+type HarnessOptions = {
+    ready?: boolean;
+    suspended?: boolean;
+};
+
+const PERIODIC_SWEEP_INTERVAL = 60 * 1000;
+
+class TestAppLifecycleService extends InjectableAppLifecycleService {}
+class TestSettingService extends InjectableSettingService<ServiceContext> {}
+
+/**
+ * Binds ConfigSync to Commonlib's real ControlService, so settings are applied in the order the plug-in uses.
+ */
+function setup(options: HarnessOptions = {}) {
+    const context = createServiceContext();
+    const settings = {
+        isConfigured: true,
+        usePluginSync: true,
+        autoSweepPlugins: true,
+        autoSweepPluginsPeriodic: true,
+        watchInternalFileChanges: false,
+        pluginSyncExtendedSetting: {},
+    };
+    const API = {
+        addLog: vi.fn(),
+        getSystemConfigDir: () => ".obsidian",
+    };
+    const appLifecycle = new TestAppLifecycleService(context, {
+        settingService: { currentSettings: () => settings },
+    } as never);
+    const setting = new TestSettingService(context, { APIService: API } as never);
+    const control = new ControlService(context, {
+        APIService: API,
+        appLifecycleService: appLifecycle,
+        databaseService: { localDatabase: { refreshSettings: vi.fn() } },
+        fileProcessingService: { commitPendingFileEvents: vi.fn(async () => true) },
+        settingService: setting,
+    } as never);
+    const handler = () => ({ addHandler: vi.fn() });
+    const services = {
+        API,
+        appLifecycle,
+        conflict: { getOptionalConflictCheckMethod: handler() },
+        control,
+        databaseEvents: { onDatabaseInitialised: handler() },
+        fileProcessing: { processOptionalFileEvent: handler() },
+        replication: { onBeforeReplicate: handler(), processVirtualDocument: handler() },
+        setting,
+    };
+    const periodicPluginSweepProcessor = { disable: vi.fn(), enable: vi.fn() };
+    const scanAllConfigFiles = vi.fn(async () => undefined);
+    const configSync = Object.create(ConfigSync.prototype) as ConfigSync;
+    Object.assign(configSync, {
+        core: { settings, services },
+        periodicPluginSweepProcessor,
+        scanAllConfigFiles,
+    });
+    configSync.onBindFunction(configSync.core, services as never);
+
+    if (options.ready ?? true) appLifecycle.markIsReady();
+    appLifecycle.setSuspended(options.suspended ?? false);
+
+    // The periodic sweep is running when the last call left it enabled with a non-zero interval.
+    const isPeriodicSweepRunning = () => {
+        const calls = [
+            ...periodicPluginSweepProcessor.disable.mock.invocationCallOrder.map((order) => ({ order, interval: 0 })),
+            ...periodicPluginSweepProcessor.enable.mock.calls.map(([interval], index) => ({
+                order: periodicPluginSweepProcessor.enable.mock.invocationCallOrder[index],
+                interval: interval as number,
+            })),
+        ].sort((a, b) => a.order - b.order);
+        return (calls[calls.length - 1]?.interval ?? 0) > 0;
+    };
+
+    return { appLifecycle, control, isPeriodicSweepRunning, periodicPluginSweepProcessor, scanAllConfigFiles };
+}
+
+describe("ConfigSync when settings are applied", () => {
+    beforeEach(() => {
+        vi.stubGlobal("activeDocument", { querySelector: vi.fn(() => null) });
+    });
+    afterEach(() => {
+        vi.unstubAllGlobals();
+    });
+
+    it.each([true, false])(
+        "does not sweep configuration files while the plug-in is suspended (ready: %s)",
+        async (ready) => {
+            const { control, isPeriodicSweepRunning, periodicPluginSweepProcessor, scanAllConfigFiles } = setup({
+                ready,
+                suspended: true,
+            });
+
+            await control.applySettings();
+
+            expect(periodicPluginSweepProcessor.disable).toHaveBeenCalled();
+            expect(scanAllConfigFiles).not.toHaveBeenCalled();
+            expect(periodicPluginSweepProcessor.enable).not.toHaveBeenCalled();
+            expect(isPeriodicSweepRunning()).toBe(false);
+        }
+    );
+
+    it("sweeps configuration files once and starts the periodic sweep while the plug-in is running", async () => {
+        const { control, isPeriodicSweepRunning, periodicPluginSweepProcessor, scanAllConfigFiles } = setup();
+
+        await control.applySettings();
+
+        expect(scanAllConfigFiles).toHaveBeenCalledOnce();
+        expect(periodicPluginSweepProcessor.enable).toHaveBeenCalledOnce();
+        expect(periodicPluginSweepProcessor.enable).toHaveBeenCalledWith(PERIODIC_SWEEP_INTERVAL);
+        expect(isPeriodicSweepRunning()).toBe(true);
+    });
+
+    it("stops the periodic sweep when all synchronisation is suspended and restarts it once on resumption", async () => {
+        const { appLifecycle, control, isPeriodicSweepRunning, periodicPluginSweepProcessor, scanAllConfigFiles } =
+            setup();
+        await control.applySettings();
+        scanAllConfigFiles.mockClear();
+        periodicPluginSweepProcessor.enable.mockClear();
+
+        appLifecycle.setSuspended(true);
+        await control.applySettings();
+
+        expect(scanAllConfigFiles).not.toHaveBeenCalled();
+        expect(periodicPluginSweepProcessor.enable).not.toHaveBeenCalled();
+        expect(isPeriodicSweepRunning()).toBe(false);
+
+        appLifecycle.setSuspended(false);
+        await control.applySettings();
+
+        expect(scanAllConfigFiles).toHaveBeenCalledOnce();
+        expect(periodicPluginSweepProcessor.enable).toHaveBeenCalledOnce();
+        expect(isPeriodicSweepRunning()).toBe(true);
+    });
+});

src/features/ConfigSync/CmdConfigSync.readiness.unit.spec.ts

@@ -0,0 +1,121 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("@/deps.ts", () => ({
+    addIcon: vi.fn(),
+    diff_match_patch: class DiffMatchPatch {},
+    normalizePath: vi.fn((path: string) => path),
+    parseYaml: vi.fn(),
+    Platform: {},
+}));
+vi.mock("./PluginDialogModal.ts", () => ({
+    PluginDialogModal: class PluginDialogModal {},
+}));
+vi.mock("@/features/HiddenFileCommon/JsonResolveModal.ts", () => ({
+    JsonResolveModal: class JsonResolveModal {},
+}));
+vi.mock("@/modules/features/InteractiveConflictResolving/ConflictResolveModal.ts", () => ({
+    ConflictResolveModal: class ConflictResolveModal {},
+}));
+// The readiness helpers come from the real LiveSyncCommands, so only its log view dependency is replaced.
+vi.mock("@/modules/features/ModuleLog.ts", () => ({
+    MARK_DONE: "",
+}));
+vi.mock("@/common/types.ts", () => ({
+    ICXHeader: "ix:",
+    PERIODIC_PLUGIN_SWEEP: 60,
+}));
+vi.mock("@/common/utils.ts", () => ({
+    cancelTask: vi.fn(),
+    EVEN: Symbol("even"),
+    isCustomisationSyncMetadata: vi.fn(),
+    isPluginMetadata: vi.fn(),
+    scheduleTask: vi.fn(),
+}));
+vi.mock("@/common/PeriodicProcessor.ts", () => ({
+    PeriodicProcessor: class PeriodicProcessor {},
+}));
+vi.mock("@/common/events.ts", () => ({
+    EVENT_REQUEST_OPEN_PLUGIN_SYNC_DIALOG: "open-plugin-sync",
+    eventHub: {
+        onEvent: vi.fn(),
+    },
+}));
+vi.mock("@/common/translation", () => ({
+    $msg: vi.fn((message: string) => message),
+}));
+vi.mock("@/common/obsidianCommunityPlugins.ts", () => ({
+    getObsidianCommunityPluginManager: vi.fn(),
+}));
+
+import { scheduleTask } from "@/common/utils.ts";
+import type { FilePath } from "@vrtmrz/livesync-commonlib/compat/common/types";
+import { ConfigSync } from "./CmdConfigSync";
+
+type LifecycleState = {
+    ready: boolean;
+    suspended: boolean;
+};
+
+const CONFIG_FILE = ".obsidian/snippets/theme.css" as FilePath;
+
+function setup(state: LifecycleState) {
+    const appLifecycle = {
+        isReady: vi.fn(() => state.ready),
+        isSuspended: vi.fn(() => state.suspended),
+    };
+    const statHidden = vi.fn(async () => ({ type: "file", ctime: 0, mtime: 1_000, size: 1 }));
+    const storeCustomizationFiles = vi.fn(async () => undefined);
+    // Obsidian adds Array.prototype.contains, which is not available under Node.
+    const recentProcessedInternalFiles = Object.assign([] as string[], {
+        contains: (key: string) => recentProcessedInternalFiles.includes(key),
+    });
+    const configSync = Object.create(ConfigSync.prototype) as ConfigSync;
+    Object.assign(configSync, {
+        core: {
+            settings: {
+                usePluginSync: true,
+                pluginSyncExtendedSetting: {},
+            },
+            services: {
+                appLifecycle,
+                API: { getSystemConfigDir: () => ".obsidian" },
+            },
+            storageAccess: { statHidden },
+        },
+        recentProcessedInternalFiles,
+        storeCustomizationFiles,
+        filenameToUnifiedKey: (path: string) => `ix:${path}`,
+    });
+    return {
+        appLifecycle,
+        configSync,
+        statHidden,
+    };
+}
+
+describe("ConfigSync readiness", () => {
+    beforeEach(() => {
+        vi.mocked(scheduleTask).mockClear();
+    });
+
+    it("leaves a configuration file event unhandled before the plug-in is ready", async () => {
+        const { appLifecycle, configSync, statHidden } = setup({ ready: false, suspended: false });
+
+        const handled = await configSync.watchVaultRawEventsAsync(CONFIG_FILE);
+
+        expect(scheduleTask).not.toHaveBeenCalled();
+        expect(statHidden).not.toHaveBeenCalled();
+        expect(handled).toBe(false);
+        expect(appLifecycle.isReady).toHaveBeenCalled();
+    });
+
+    it("schedules a configuration file event for storing once the plug-in is ready", async () => {
+        const { configSync, statHidden } = setup({ ready: true, suspended: false });
+
+        await expect(configSync.watchVaultRawEventsAsync(CONFIG_FILE)).resolves.toBe(true);
+
+        expect(statHidden).toHaveBeenCalledWith(CONFIG_FILE);
+        expect(scheduleTask).toHaveBeenCalledOnce();
+        expect(scheduleTask).toHaveBeenCalledWith(`ix:${CONFIG_FILE}`, 100, expect.any(Function));
+    });
+});

src/features/ConfigSync/CmdConfigSync.ts

@@ -1198,20 +1198,11 @@ export class ConfigSync extends LiveSyncCommands {
         }
         return true;
     }
-    async _everyRealizeSettingSyncMode(): Promise<boolean> {
+    _everyRealizeSettingSyncMode(): Promise<boolean> {
+        // applySettings calls onResuming after this handler when synchronisation is active.
+        // That handler scans and restarts the sweep; doing so here would scan twice.
         this.periodicPluginSweepProcessor?.disable();
-        if (!this._isMainReady) return true;
-        if (!this._isMainSuspended()) return true;
-        if (!this.isThisModuleEnabled()) return true;
-        if (this.settings.autoSweepPlugins) {
-            await this.scanAllConfigFiles(false);
-        }
-        this.periodicPluginSweepProcessor.enable(
-            this.settings.autoSweepPluginsPeriodic && !this.settings.watchInternalFileChanges
-                ? PERIODIC_PLUGIN_SWEEP * 1000
-                : 0
-        );
-        return true;
+        return Promise.resolve(true);
     }
 
     recentProcessedInternalFiles = [] as string[];
@@ -1488,7 +1479,7 @@ export class ConfigSync extends LiveSyncCommands {
     }
 
     async watchVaultRawEventsAsync(path: FilePath) {
-        if (!this._isMainReady) return false;
+        if (!this._isMainReady()) return false;
         if (this._isMainSuspended()) return false;
         if (!this.isThisModuleEnabled()) return false;
         // if (!this.isTargetPath(path)) return false;

updates.md

@@ -12,6 +12,12 @@ Earlier releases remain available in the 1.0 release history, the 1.0 preview hi
 
 ## Unreleased
 
+### Customisation Sync
+
+#### Fixed
+
+- Configuration file events are left for the next scan until the plug-in is ready. Applying settings while synchronisation is suspended stops the periodic scan without scanning configuration files. When synchronisation resumes, the normal resume handler scans once and restarts the periodic scan.
+
 ## 1.0.34
 
 2nd October, 2026