Merge pull request #1039 from andrewleech/fix/float-mtime-mobile-crash

fix: prevent float mtime from crashing mobile clients

src/apps/cli/managers/CLIStorageEventManagerAdapter.ts

@@ -121,8 +121,10 @@ class CLIWatchAdapter implements IStorageEventWatchAdapter {
         return {
             path: path.relative(this.basePath, filePath).replace(/\\/g, "/") as FilePath,
             stat: {
-                ctime: stats?.ctimeMs ?? Date.now(),
-                mtime: stats?.mtimeMs ?? Date.now(),
+                // Floor to integer milliseconds; Linux fs.Stats.*Ms carry sub-millisecond
+                // precision, and timestamps are stored as integer ms everywhere else.
+                ctime: Math.floor(stats?.ctimeMs ?? Date.now()),
+                mtime: Math.floor(stats?.mtimeMs ?? Date.now()),
                 size: stats?.size ?? 0,
                 type: "file",
             },

src/apps/cli/managers/CLIStorageEventManagerAdapter.unit.spec.ts

@@ -84,6 +84,27 @@ describe("CLIStorageEventManagerAdapter", () => {
         expect(created.stat?.size).toBe(42);
     });
 
+    it("floors sub-millisecond stat timestamps so mobile clients do not receive floats", async () => {
+        const basePath = "/vault/base";
+        const adapter = new CLIStorageEventManagerAdapter(basePath, undefined, true);
+        const handlers = makeHandlers();
+
+        await adapter.watch.beginWatch(handlers);
+
+        const addCallback = mockWatcher.on.mock.calls.find(([event]) => event === "add")![1] as (
+            filePath: string,
+            stats: any
+        ) => void;
+
+        // Linux fs.Stats carry nanosecond-derived sub-millisecond precision.
+        const floatStats = { ctimeMs: 1778511180024.462, mtimeMs: 1778511180999.913, size: 7 };
+        addCallback(`${basePath}/note.md`, floatStats);
+
+        const created = (handlers.onCreate as ReturnType<typeof vi.fn>).mock.calls[0][0] as NodeFile;
+        expect(created.stat?.ctime).toBe(1778511180024);
+        expect(created.stat?.mtime).toBe(1778511180999);
+    });
+
     it("close() calls watcher.close()", async () => {
         const adapter = new CLIStorageEventManagerAdapter("/base", undefined, true);
         const handlers = makeHandlers();

src/serviceModules/FileSystemAdapters/ObsidianStorageAdapter.ts

@@ -2,6 +2,7 @@ import type { UXDataWriteOptions } from "@vrtmrz/livesync-commonlib/compat/commo
 import type { IStorageAdapter } from "@vrtmrz/livesync-commonlib/compat/serviceModules/adapters";
 import { toArrayBuffer } from "@vrtmrz/livesync-commonlib/compat/serviceModules/FileAccessBase";
 import type { Stat, App } from "obsidian";
+import { toIntegerTimestamps } from "./sanitizeWriteOptions";
 
 /**
  * Storage adapter implementation for Obsidian
@@ -40,15 +41,15 @@ export class ObsidianStorageAdapter implements IStorageAdapter<Stat> {
     }
 
     async write(path: string, data: string, options?: UXDataWriteOptions): Promise<void> {
-        return await this.app.vault.adapter.write(path, data, options);
+        return await this.app.vault.adapter.write(path, data, toIntegerTimestamps(options));
     }
 
     async writeBinary(path: string, data: ArrayBuffer, options?: UXDataWriteOptions): Promise<void> {
-        return await this.app.vault.adapter.writeBinary(path, toArrayBuffer(data), options);
+        return await this.app.vault.adapter.writeBinary(path, toArrayBuffer(data), toIntegerTimestamps(options));
     }
 
     async append(path: string, data: string, options?: UXDataWriteOptions): Promise<void> {
-        return await this.app.vault.adapter.append(path, data, options);
+        return await this.app.vault.adapter.append(path, data, toIntegerTimestamps(options));
     }
 
     list(basePath: string): Promise<{ files: string[]; folders: string[] }> {

src/serviceModules/FileSystemAdapters/ObsidianStorageAdapter.unit.spec.ts

@@ -0,0 +1,32 @@
+import { describe, expect, it, vi } from "vitest";
+import type { App } from "obsidian";
+import { ObsidianStorageAdapter } from "./ObsidianStorageAdapter";
+
+describe("ObsidianStorageAdapter", () => {
+    it("floors write-option timestamps before calling Obsidian storage methods", async () => {
+        const write = vi.fn().mockResolvedValue(undefined);
+        const writeBinary = vi.fn().mockResolvedValue(undefined);
+        const append = vi.fn().mockResolvedValue(undefined);
+        const app = {
+            vault: {
+                adapter: {
+                    write,
+                    writeBinary,
+                    append,
+                },
+            },
+        } as unknown as App;
+        const adapter = new ObsidianStorageAdapter(app);
+        const options = { ctime: 1778511180024.462, mtime: 1778511180999.913 };
+        const expectedOptions = { ctime: 1778511180024, mtime: 1778511180999 };
+
+        await adapter.write("note.md", "text", options);
+        await adapter.writeBinary("image.bin", new ArrayBuffer(0), options);
+        await adapter.append("log.md", "text", options);
+
+        expect(write).toHaveBeenCalledWith("note.md", "text", expectedOptions);
+        expect(writeBinary).toHaveBeenCalledWith("image.bin", expect.any(ArrayBuffer), expectedOptions);
+        expect(append).toHaveBeenCalledWith("log.md", "text", expectedOptions);
+        expect(options).toEqual({ ctime: 1778511180024.462, mtime: 1778511180999.913 });
+    });
+});

src/serviceModules/FileSystemAdapters/ObsidianVaultAdapter.ts

@@ -2,6 +2,7 @@ import type { UXDataWriteOptions } from "@vrtmrz/livesync-commonlib/compat/commo
 import type { IVaultAdapter } from "@vrtmrz/livesync-commonlib/compat/serviceModules/adapters";
 import { toArrayBuffer } from "@vrtmrz/livesync-commonlib/compat/serviceModules/FileAccessBase";
 import type { TFile, App, TFolder } from "obsidian";
+import { toIntegerTimestamps } from "./sanitizeWriteOptions";
 
 /**
  * Vault adapter implementation for Obsidian
@@ -23,19 +24,19 @@ export class ObsidianVaultAdapter implements IVaultAdapter<TFile, TFolder> {
     }
 
     async modify(file: TFile, data: string, options?: UXDataWriteOptions): Promise<void> {
-        return await this.app.vault.modify(file, data, options);
+        return await this.app.vault.modify(file, data, toIntegerTimestamps(options));
     }
 
     async modifyBinary(file: TFile, data: ArrayBuffer, options?: UXDataWriteOptions): Promise<void> {
-        return await this.app.vault.modifyBinary(file, toArrayBuffer(data), options);
+        return await this.app.vault.modifyBinary(file, toArrayBuffer(data), toIntegerTimestamps(options));
     }
 
     async create(path: string, data: string, options?: UXDataWriteOptions): Promise<TFile> {
-        return await this.app.vault.create(path, data, options);
+        return await this.app.vault.create(path, data, toIntegerTimestamps(options));
     }
 
     async createBinary(path: string, data: ArrayBuffer, options?: UXDataWriteOptions): Promise<TFile> {
-        return await this.app.vault.createBinary(path, toArrayBuffer(data), options);
+        return await this.app.vault.createBinary(path, toArrayBuffer(data), toIntegerTimestamps(options));
     }
 
     async rename(file: TFile, newPath: string): Promise<void> {

src/serviceModules/FileSystemAdapters/ObsidianVaultAdapter.unit.spec.ts

@@ -2,7 +2,7 @@ import { describe, expect, it, vi } from "vitest";
 import type { App, TFile } from "obsidian";
 import { ObsidianVaultAdapter } from "./ObsidianVaultAdapter";
 
-describe("ObsidianVaultAdapter.read", () => {
+describe("ObsidianVaultAdapter", () => {
     it("preserves a UTF-8 BOM so the content size matches the file stat", async () => {
         const path = "Transcripts/字幕.md";
         const contentWithoutBom = "字幕の検証行です。\n";
@@ -34,4 +34,34 @@ describe("ObsidianVaultAdapter.read", () => {
         expect(adapterRead).toHaveBeenCalledWith(path);
         expect(read).not.toHaveBeenCalled();
     });
+
+    it("floors write-option timestamps before calling Obsidian vault methods", async () => {
+        const modify = vi.fn().mockResolvedValue(undefined);
+        const modifyBinary = vi.fn().mockResolvedValue(undefined);
+        const create = vi.fn().mockResolvedValue({});
+        const createBinary = vi.fn().mockResolvedValue({});
+        const app = {
+            vault: {
+                modify,
+                modifyBinary,
+                create,
+                createBinary,
+            },
+        } as unknown as App;
+        const file = { path: "note.md" } as TFile;
+        const adapter = new ObsidianVaultAdapter(app);
+        const options = { ctime: 1778511180024.462, mtime: 1778511180999.913 };
+        const expectedOptions = { ctime: 1778511180024, mtime: 1778511180999 };
+
+        await adapter.modify(file, "text", options);
+        await adapter.modifyBinary(file, new ArrayBuffer(0), options);
+        await adapter.create("created.md", "text", options);
+        await adapter.createBinary("created.bin", new ArrayBuffer(0), options);
+
+        expect(modify).toHaveBeenCalledWith(file, "text", expectedOptions);
+        expect(modifyBinary).toHaveBeenCalledWith(file, expect.any(ArrayBuffer), expectedOptions);
+        expect(create).toHaveBeenCalledWith("created.md", "text", expectedOptions);
+        expect(createBinary).toHaveBeenCalledWith("created.bin", expect.any(ArrayBuffer), expectedOptions);
+        expect(options).toEqual({ ctime: 1778511180024.462, mtime: 1778511180999.913 });
+    });
 });

src/serviceModules/FileSystemAdapters/sanitizeWriteOptions.ts

@@ -0,0 +1,25 @@
+import type { UXDataWriteOptions } from "@vrtmrz/livesync-commonlib/compat/common/types";
+
+/**
+ * Coerce the timestamp fields of a write-options object to integer milliseconds.
+ *
+ * On mobile, Obsidian forwards `mtime`/`ctime` to Capacitor's
+ * Filesystem.setTimes, whose native binding casts the value to a Java `Long`.
+ * A non-integer (float) timestamp makes that cast throw
+ * `ClassCastException: Double cannot be cast to Long`, which crashes the app on
+ * launch as soon as such a document is replicated in. Float timestamps can
+ * enter the database from any client that stores `fs.Stats.mtimeMs` without
+ * flooring. Flooring at the storage boundary guarantees every Obsidian write
+ * carries an integer, so a float timestamp already present in the mesh cannot
+ * brick the app.
+ *
+ * Returns a shallow copy so the caller's options object is not mutated; passes
+ * `undefined` through unchanged.
+ */
+export function toIntegerTimestamps(options?: UXDataWriteOptions): UXDataWriteOptions | undefined {
+    if (!options) return options;
+    const sanitized: UXDataWriteOptions = { ...options };
+    if (typeof sanitized.mtime === "number") sanitized.mtime = Math.floor(sanitized.mtime);
+    if (typeof sanitized.ctime === "number") sanitized.ctime = Math.floor(sanitized.ctime);
+    return sanitized;
+}

updates.md

@@ -12,6 +12,13 @@ Earlier releases remain available in the 0.25 release history and the legacy rel
 
 ## Unreleased
 
+### Synchronisation and storage
+
+#### Fixed
+
+- Fractional file timestamps no longer cause affected mobile clients to crash after synchronisation (#1087, PR #1039). Thank you to @andrewleech for the contribution!
+    - Timestamps are now normalised in the command-line tool and before Obsidian's native file-system writes.
+
 ## 1.0.10
 
 9th August, 2026