Fixes for workspaceState sync

src/vs/platform/userDataSync/common/abstractSynchronizer.ts

@@ -102,7 +102,7 @@ interface IEditableResourcePreview extends IBaseResourcePreview, IResourcePrevie
 	acceptResult?: IAcceptResult;
 }
 
-interface ISyncResourcePreview extends IBaseSyncResourcePreview {
+export interface ISyncResourcePreview extends IBaseSyncResourcePreview {
 	readonly remoteUserData: IRemoteUserData;
 	readonly lastSyncUserData: IRemoteUserData | null;
 	readonly resourcePreviews: IEditableResourcePreview[];

src/vs/platform/userDataSync/common/userDataSync.ts

@@ -363,6 +363,7 @@ export interface IGlobalState {
 export interface IWorkspaceState {
 	folders: IWorkspaceStateFolder[];
 	storage: IStringDictionary<string>;
+	version: number;
 }
 
 export interface IWorkspaceStateFolder {

src/vs/workbench/contrib/editSessions/common/workspaceStateSync.ts

@@ -15,7 +15,7 @@ import { IStorageService, StorageScope, StorageTarget } from 'vs/platform/storag
 import { ITelemetryService } from 'vs/platform/telemetry/common/telemetry';
 import { IUriIdentityService } from 'vs/platform/uriIdentity/common/uriIdentity';
 import { IUserDataProfile } from 'vs/platform/userDataProfile/common/userDataProfile';
-import { AbstractSynchroniser, IAcceptResult, IMergeResult, IResourcePreview } from 'vs/platform/userDataSync/common/abstractSynchronizer';
+import { AbstractSynchroniser, IAcceptResult, IMergeResult, IResourcePreview, ISyncResourcePreview } from 'vs/platform/userDataSync/common/abstractSynchronizer';
 import { IRemoteUserData, IResourceRefHandle, IUserDataSyncBackupStoreService, IUserDataSyncConfiguration, IUserDataSyncEnablementService, IUserDataSyncLogService, IUserDataSyncStoreService, IUserDataSynchroniser, IWorkspaceState, SyncResource } from 'vs/platform/userDataSync/common/userDataSync';
 import { IEditSessionsStorageService } from 'vs/workbench/contrib/editSessions/common/editSessions';
 import { IWorkspaceIdentityService } from 'vs/workbench/services/workspaces/common/workspaceIdentityService';
@@ -82,6 +82,9 @@ export class WorkspaceStateSynchroniser extends AbstractSynchroniser implements
 			return;
 		}
 
+		// Ensure we have latest state by sending out onWillSaveState event
+		await this.storageService.flush();
+
 		const keys = this.storageService.keys(StorageScope.WORKSPACE, StorageTarget.USER);
 		if (!keys.length) {
 			return;
@@ -95,16 +98,28 @@ export class WorkspaceStateSynchroniser extends AbstractSynchroniser implements
 			}
 		});
 
-		const content: IWorkspaceState = { folders, storage: contributedData };
+		const content: IWorkspaceState = { folders, storage: contributedData, version: this.version };
 		this.editSessionsStorageService.write('workspaceState', stringify(content));
 	}
 
-	protected override async applyResult(remoteUserData: IRemoteUserData): Promise<void> {
-		const cancellationTokenSource = new CancellationTokenSource();
-		const remoteWorkspaceState: IWorkspaceState = remoteUserData.syncData ? parse(remoteUserData.syncData.content) : null;
+	override async apply(): Promise<ISyncResourcePreview | null> {
+		const resource = await this.editSessionsStorageService.read('workspaceState', undefined);
+		if (!resource) {
+			return null;
+		}
+
+		const remoteWorkspaceState: IWorkspaceState = parse(resource.content);
 		if (!remoteWorkspaceState) {
 			this.logService.info('Skipping initializing workspace state because remote workspace state does not exist.');
-			return;
+			return null;
+		}
+
+		// Evaluate whether storage is applicable for current workspace
+		const cancellationTokenSource = new CancellationTokenSource();
+		const replaceUris = await this.workspaceIdentityService.matches(remoteWorkspaceState.folders, cancellationTokenSource.token);
+		if (!replaceUris) {
+			this.logService.info('Skipping initializing workspace state because remote workspace state does not match current workspace.');
+			return null;
 		}
 
 		const storage: IStringDictionary<any> = {};
@@ -113,9 +128,7 @@ export class WorkspaceStateSynchroniser extends AbstractSynchroniser implements
 		}
 
 		if (Object.keys(storage).length) {
-			// Evaluate whether storage is applicable for current workspace
-			const replaceUris = await this.workspaceIdentityService.matches(remoteWorkspaceState.folders, cancellationTokenSource.token);
-			// If so, initialize storage with remote storage
+			// Initialize storage with remote storage
 			for (const key of Object.keys(storage)) {
 				// Deserialize the stored state
 				try {
@@ -129,8 +142,13 @@ export class WorkspaceStateSynchroniser extends AbstractSynchroniser implements
 				}
 			}
 		}
+		return null;
 	}
 
+	// TODO@joyceerhl implement AbstractSynchronizer in full
+	protected override applyResult(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, result: [IResourcePreview, IAcceptResult][], force: boolean): Promise<void> {
+		throw new Error('Method not implemented.');
+	}
 	protected override async generateSyncPreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, isRemoteDataFromCurrentMachine: boolean, userDataSyncConfiguration: IUserDataSyncConfiguration, token: CancellationToken): Promise<IResourcePreview[]> {
 		return [];
 	}

src/vs/workbench/services/workspaces/common/workspaceIdentityService.ts

@@ -16,7 +16,7 @@ import { IWorkspaceContextService, IWorkspaceFolder } from 'vs/platform/workspac
 export const IWorkspaceIdentityService = createDecorator<IWorkspaceIdentityService>('IWorkspaceIdentityService');
 export interface IWorkspaceIdentityService {
 	_serviceBrand: undefined;
-	matches(folders: IWorkspaceStateFolder[], cancellationToken: CancellationToken): Promise<(obj: any) => any>;
+	matches(folders: IWorkspaceStateFolder[], cancellationToken: CancellationToken): Promise<((obj: any) => any) | false>;
 	getWorkspaceStateFolders(cancellationToken: CancellationToken): Promise<IWorkspaceStateFolder[]>;
 }
 
@@ -40,7 +40,7 @@ export class WorkspaceIdentityService implements IWorkspaceIdentityService {
 		return workspaceStateFolders;
 	}
 
-	async matches(incomingWorkspaceFolders: IWorkspaceStateFolder[], cancellationToken: CancellationToken): Promise<(value: any) => any> {
+	async matches(incomingWorkspaceFolders: IWorkspaceStateFolder[], cancellationToken: CancellationToken): Promise<((value: any) => any) | false> {
 		const incomingToCurrentWorkspaceFolderUris: { [key: string]: string } = {};
 
 		const incomingIdentitiesToIncomingWorkspaceFolders: { [key: string]: string } = {};
@@ -81,7 +81,7 @@ export class WorkspaceIdentityService implements IWorkspaceIdentityService {
 				continue;
 			}
 
-			return () => { };
+			return false;
 		}
 
 		const convertUri = (uriToConvert: URI) => {