diff --git a/src/vs/platform/userDataSync/common/abstractSynchronizer.ts b/src/vs/platform/userDataSync/common/abstractSynchronizer.ts
index 06b1d0d95d74ef99c29a57cb1015a65c82964e7c..fd38c3bac802cfa1f94041ea121b3114f81a739c 100644
--- a/src/vs/platform/userDataSync/common/abstractSynchronizer.ts
+++ b/src/vs/platform/userDataSync/common/abstractSynchronizer.ts
@@ -151,7 +151,7 @@ export abstract class AbstractSynchroniser extends Disposable {
 
 		const lastSyncUserData = await this.getLastSyncUserData();
 		const remoteUserData = await this.getRemoteUserData(lastSyncUserData);
-		return this.getPreview(remoteUserData, lastSyncUserData);
+		return this.generatePreview(remoteUserData, lastSyncUserData);
 	}
 
 	protected async doSync(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<SyncStatus> {
@@ -295,7 +295,7 @@ export abstract class AbstractSynchroniser extends Disposable {
 
 	protected abstract readonly version: number;
 	protected abstract performSync(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<SyncStatus>;
-	protected abstract getPreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<ISyncPreviewResult>;
+	protected abstract generatePreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<ISyncPreviewResult>;
 }
 
 export interface IFileSyncPreviewResult extends ISyncPreviewResult {
diff --git a/src/vs/platform/userDataSync/common/extensionsSync.ts b/src/vs/platform/userDataSync/common/extensionsSync.ts
index 01dd9e12658d1ffd5184bae123c71f0cdaa2db8e..33901ed48ce795d6a7793764055684d25ab611f8 100644
--- a/src/vs/platform/userDataSync/common/extensionsSync.ts
+++ b/src/vs/platform/userDataSync/common/extensionsSync.ts
@@ -171,12 +171,12 @@ export class ExtensionsSynchroniser extends AbstractSynchroniser implements IUse
 	}
 
 	protected async performSync(remoteUserData: IRemoteUserData, lastSyncUserData: ILastSyncUserData | null): Promise<SyncStatus> {
-		const previewResult = await this.getPreview(remoteUserData, lastSyncUserData);
+		const previewResult = await this.generatePreview(remoteUserData, lastSyncUserData);
 		await this.apply(previewResult);
 		return SyncStatus.Idle;
 	}
 
-	protected async getPreview(remoteUserData: IRemoteUserData, lastSyncUserData: ILastSyncUserData | null): Promise<IExtensionsSyncPreviewResult> {
+	protected async generatePreview(remoteUserData: IRemoteUserData, lastSyncUserData: ILastSyncUserData | null): Promise<IExtensionsSyncPreviewResult> {
 		const remoteExtensions: ISyncExtension[] | null = remoteUserData.syncData ? this.parseExtensions(remoteUserData.syncData) : null;
 		const lastSyncExtensions: ISyncExtension[] | null = lastSyncUserData ? this.parseExtensions(lastSyncUserData.syncData!) : null;
 		const skippedExtensions: ISyncExtension[] = lastSyncUserData ? lastSyncUserData.skippedExtensions || [] : [];
diff --git a/src/vs/platform/userDataSync/common/globalStateSync.ts b/src/vs/platform/userDataSync/common/globalStateSync.ts
index e7beda1be2fc531dc59c229a04995a33875b20e5..682a8f3a46c3bc533a328ac110a1fa7a4cfb4c30 100644
--- a/src/vs/platform/userDataSync/common/globalStateSync.ts
+++ b/src/vs/platform/userDataSync/common/globalStateSync.ts
@@ -162,12 +162,12 @@ export class GlobalStateSynchroniser extends AbstractSynchroniser implements IUs
 	}
 
 	protected async performSync(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<SyncStatus> {
-		const result = await this.getPreview(remoteUserData, lastSyncUserData);
+		const result = await this.generatePreview(remoteUserData, lastSyncUserData);
 		await this.apply(result);
 		return SyncStatus.Idle;
 	}
 
-	protected async getPreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<IGlobalSyncPreviewResult> {
+	protected async generatePreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<IGlobalSyncPreviewResult> {
 		const remoteGlobalState: IGlobalState = remoteUserData.syncData ? JSON.parse(remoteUserData.syncData.content) : null;
 		const lastSyncGlobalState: IGlobalState = lastSyncUserData && lastSyncUserData.syncData ? JSON.parse(lastSyncUserData.syncData.content) : null;
 
diff --git a/src/vs/platform/userDataSync/common/keybindingsSync.ts b/src/vs/platform/userDataSync/common/keybindingsSync.ts
index 4d16ffb66e9936f469d290c0157f3a2aee934419..ed6943af053155d3453815c153c5629961749915 100644
--- a/src/vs/platform/userDataSync/common/keybindingsSync.ts
+++ b/src/vs/platform/userDataSync/common/keybindingsSync.ts
@@ -258,14 +258,14 @@ export class KeybindingsSynchroniser extends AbstractJsonFileSynchroniser implem
 		this.syncPreviewResultPromise = null;
 	}
 
-	protected getPreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<IFileSyncPreviewResult> {
+	private getPreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<IFileSyncPreviewResult> {
 		if (!this.syncPreviewResultPromise) {
 			this.syncPreviewResultPromise = createCancelablePromise(token => this.generatePreview(remoteUserData, lastSyncUserData, token));
 		}
 		return this.syncPreviewResultPromise;
 	}
 
-	private async generatePreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, token: CancellationToken): Promise<IFileSyncPreviewResult> {
+	protected async generatePreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, token: CancellationToken = CancellationToken.None): Promise<IFileSyncPreviewResult> {
 		const remoteContent = remoteUserData.syncData ? this.getKeybindingsContentFromSyncContent(remoteUserData.syncData.content) : null;
 		const lastSyncContent = lastSyncUserData && lastSyncUserData.syncData ? this.getKeybindingsContentFromSyncContent(lastSyncUserData.syncData.content) : null;
 		// Get file content last to get the latest
diff --git a/src/vs/platform/userDataSync/common/settingsSync.ts b/src/vs/platform/userDataSync/common/settingsSync.ts
index a908a8e5c3a5ba1840a810af16a4a4a15aba0a54..e159e8188c3e8cd6376f5e80459066691857742a 100644
--- a/src/vs/platform/userDataSync/common/settingsSync.ts
+++ b/src/vs/platform/userDataSync/common/settingsSync.ts
@@ -309,14 +309,14 @@ export class SettingsSynchroniser extends AbstractJsonFileSynchroniser {
 		this.syncPreviewResultPromise = null;
 	}
 
-	protected getPreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, resolvedConflicts: { key: string, value: any }[] = []): Promise<IFileSyncPreviewResult> {
+	private getPreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, resolvedConflicts: { key: string, value: any }[] = []): Promise<IFileSyncPreviewResult> {
 		if (!this.syncPreviewResultPromise) {
 			this.syncPreviewResultPromise = createCancelablePromise(token => this.generatePreview(remoteUserData, lastSyncUserData, resolvedConflicts, token));
 		}
 		return this.syncPreviewResultPromise;
 	}
 
-	protected async generatePreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, resolvedConflicts: { key: string, value: any }[], token: CancellationToken): Promise<IFileSyncPreviewResult> {
+	protected async generatePreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, resolvedConflicts: { key: string, value: any }[] = [], token: CancellationToken = CancellationToken.None): Promise<IFileSyncPreviewResult> {
 		const fileContent = await this.getLocalFileContent();
 		const formattingOptions = await this.getFormattingOptions();
 		const remoteSettingsSyncContent = this.getSettingsSyncContent(remoteUserData);
diff --git a/src/vs/platform/userDataSync/common/snippetsSync.ts b/src/vs/platform/userDataSync/common/snippetsSync.ts
index 3afd332c520498684b9d919fe4dbc00b70d95b2c..a055d21fd57acc74d59452fbe6395a73d12ea5db 100644
--- a/src/vs/platform/userDataSync/common/snippetsSync.ts
+++ b/src/vs/platform/userDataSync/common/snippetsSync.ts
@@ -211,7 +211,7 @@ export class SnippetsSynchroniser extends AbstractSynchroniser implements IUserD
 			let previewResult = await this.syncPreviewResultPromise!;
 			this.cancel();
 			previewResult.resolvedConflicts[key] = content || null;
-			this.syncPreviewResultPromise = createCancelablePromise(token => this.generatePreview(previewResult.local, previewResult.remoteUserData, previewResult.lastSyncUserData, previewResult.resolvedConflicts, token));
+			this.syncPreviewResultPromise = createCancelablePromise(token => this.doGeneratePreview(previewResult.local, previewResult.remoteUserData, previewResult.lastSyncUserData, previewResult.resolvedConflicts, token));
 			previewResult = await this.syncPreviewResultPromise;
 			this.setConflicts(previewResult.conflicts);
 			if (!this.conflicts.length) {
@@ -258,8 +258,7 @@ export class SnippetsSynchroniser extends AbstractSynchroniser implements IUserD
 
 	protected getPreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<ISinppetsSyncPreviewResult> {
 		if (!this.syncPreviewResultPromise) {
-			this.syncPreviewResultPromise = createCancelablePromise(token => this.getSnippetsFileContents()
-				.then(local => this.generatePreview(local, remoteUserData, lastSyncUserData, {}, token)));
+			this.syncPreviewResultPromise = createCancelablePromise(token => this.generatePreview(remoteUserData, lastSyncUserData, token));
 		}
 		return this.syncPreviewResultPromise;
 	}
@@ -278,7 +277,12 @@ export class SnippetsSynchroniser extends AbstractSynchroniser implements IUserD
 		}
 	}
 
-	private async generatePreview(local: IStringDictionary<IFileContent>, remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, resolvedConflicts: IStringDictionary<string | null>, token: CancellationToken): Promise<ISinppetsSyncPreviewResult> {
+	protected async generatePreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, token: CancellationToken = CancellationToken.None): Promise<ISinppetsSyncPreviewResult> {
+		return this.getSnippetsFileContents()
+			.then(local => this.doGeneratePreview(local, remoteUserData, lastSyncUserData, {}, token));
+	}
+
+	private async doGeneratePreview(local: IStringDictionary<IFileContent>, remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null, resolvedConflicts: IStringDictionary<string | null> = {}, token: CancellationToken = CancellationToken.None): Promise<ISinppetsSyncPreviewResult> {
 		const localSnippets = this.toSnippetsContents(local);
 		const remoteSnippets: IStringDictionary<string> | null = remoteUserData.syncData ? this.parseSnippets(remoteUserData.syncData) : null;
 		const lastSyncSnippets: IStringDictionary<string> | null = lastSyncUserData ? this.parseSnippets(lastSyncUserData.syncData!) : null;
diff --git a/src/vs/platform/userDataSync/test/common/synchronizer.test.ts b/src/vs/platform/userDataSync/test/common/synchronizer.test.ts
index 94eeeed83a3f416a8c51c30c7f963232a51d70b7..3c2583e46264dd2b59e5877925db05fe15a628a3 100644
--- a/src/vs/platform/userDataSync/test/common/synchronizer.test.ts
+++ b/src/vs/platform/userDataSync/test/common/synchronizer.test.ts
@@ -49,7 +49,7 @@ class TestSynchroniser extends AbstractSynchroniser {
 		this.syncBarrier.open();
 	}
 
-	protected async getPreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<ISyncPreviewResult> {
+	protected async generatePreview(remoteUserData: IRemoteUserData, lastSyncUserData: IRemoteUserData | null): Promise<ISyncPreviewResult> {
 		return { hasLocalChanged: false, hasRemoteChanged: false };
 	}