Comments & make ping refreshable

frontend/sync-client/src/errors/errors.ts

@@ -28,6 +28,11 @@ export class ConflictingPathError extends Error {
 
 export class PermanentSyncError extends Error {}
 
+/**
+ * Retry reconciliation against fresh local state. Raised for stale identity plans
+ * and local files that change during history recovery. Syncer schedules another
+ * pass without reporting this as a sync failure.
+ */
 export class LocalChangesDuringReconciliation extends Error {}
 
 // The server rejected a checkpoint from a discarded/restored history.

frontend/sync-client/src/file-operations/file-change-session.ts

@@ -52,7 +52,7 @@ export class FileChangeSession {
             return;
         }
 
-        this.options.checkpoint.assertUnchanged();
+        this.options.assertUnchanged();
     }
 
     public beforeFileMutation(): void {
@@ -64,7 +64,9 @@ export class FileChangeSession {
         const { localChanges, isProtectedPath } = this.options;
         await localChanges.flush();
 
-        this.abortIfStale();
+        if (!this.mutationsStarted) {
+            this.options.assertUnchanged();
+        }
 
         for (const change of getUnappliedChanges(
             this.planned,

frontend/sync-client/src/file-operations/file-renamer.test.ts

@@ -4,7 +4,6 @@ import { test } from "node:test";
 import { MemoryDisk } from "../../../test-support/storage";
 import { Database, createEmptyDatabase } from "../persistence/database";
 import type { ServerConfig } from "../services/server-config";
-import { LocalChangeCheckpoint } from "../sync-operations/local-change-checkpoint";
 import { hash } from "../utils/hash";
 import { FileOperations } from "./file-operations";
 
@@ -27,7 +26,6 @@ test("a path swap uses a conflict path only as a temporary destination", async (
         async () => undefined
     );
     const files = new FileOperations(disk, database, {} as ServerConfig);
-    const checkpoint = new LocalChangeCheckpoint({ generation: 0 });
     const renames: string[] = [];
     disk.boundary = (label): void => {
         if (label.startsWith("visible:rename:")) {
@@ -37,7 +35,7 @@ test("a path swap uses a conflict path only as a temporary destination", async (
 
     const next = structuredClone(database.state);
     next.actualFileManifest = { a: "b.md", b: "a.md" };
-    await files.applyChanges(next, checkpoint);
+    await files.applyChanges(next, () => undefined);
 
     assert.deepEqual(renames, [
         "b.md->b (conflict b).md", // Free B without losing its contents.

frontend/sync-client/src/persistence/database.ts

@@ -12,7 +12,7 @@ export interface ContentHead {
 }
 
 export interface DocumentState {
-    // A null version retains only the clean hash after a server history reset.
+    // A null version retains an old-history hash until a scan can classify edits.
     base?: { vaultUpdateId: VaultUpdateId | null; hash: string };
 
     // Last observed disk hash; an empty string means a notification awaits scanning.

frontend/sync-client/src/services/server-config.test.ts

@@ -13,9 +13,8 @@ const config = {
     mergeableFileExtensions: ["md"],
     serverVersion: "test"
 };
-const make = (fetch: typeof globalThis.fetch): ServerConfig =>
-    new ServerConfig(
-        new SyncService(
+const make = (fetch: typeof globalThis.fetch): ServerConfig => {
+    const service = new SyncService(
         "device",
         new Settings(
             new Logger(),
@@ -23,9 +22,14 @@ const make = (fetch: typeof globalThis.fetch): ServerConfig =>
             async () => undefined
         ),
         fetch,
-            { get: () => undefined, save: async () => undefined }
-        )
+        {
+            get: (): undefined => undefined,
+            save: async (): Promise<void> => undefined
+        }
     );
+    service.resume();
+    return new ServerConfig(service);
+};
 
 test("configuration shares one validated request and retries failures", async () => {
     let calls = 0;

frontend/sync-client/src/services/server-config.ts

@@ -53,7 +53,7 @@ export class ServerConfig {
     public async getConfig(): Promise<ServerConfigResponse> {
         if (!this.config) {
             const pending = this.syncService
-                .getServerConfig()
+                .getServerConfig(false)
                 .then((config) => {
                     ServerConfig.validateConfig(config);
                     return config;

frontend/sync-client/src/services/sync-service.ts

@@ -46,8 +46,13 @@ export class SyncService {
         await this.history.save(undefined);
     }
 
-    public async getServerConfig(): Promise<ServerConfigResponse> {
-        return this.request("/config", { ignoreAborts: true });
+    public async getServerConfig(
+        ignoreAborts = true
+    ): Promise<ServerConfigResponse> {
+        return this.request("/config", {
+            ignoreAborts,
+            recordCheckpoint: false
+        });
     }
 
     public async getVaultSnapshot(): Promise<VaultSnapshot> {
@@ -119,12 +124,14 @@ export class SyncService {
         {
             body,
             ignoreAborts = false,
+            recordCheckpoint = true,
             decode = async (response): Promise<T> =>
                 // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion -- Endpoint methods supply the generated protocol response type.
                 response.json() as Promise<T>
         }: {
             body?: unknown;
             ignoreAborts?: boolean;
+            recordCheckpoint?: boolean;
             decode?: (response: Response) => Promise<T>;
         } = {}
     ): Promise<T> {
@@ -169,7 +176,7 @@ export class SyncService {
         }
 
         // Finish metadata saves even if the transport is paused meanwhile.
-        if (!ignoreAborts) {
+        if (!ignoreAborts && recordCheckpoint) {
             await this.recordHistory(response);
         }