Auto converting let -> const where possible in mainthread and extHost

Const provides better type guards and can make logic clearer

src/vs/workbench/api/node/extHost.api.impl.ts

@@ -92,7 +92,7 @@ export function createApiFactory(
 	extHostStorage: ExtHostStorage
 ): IExtensionApiFactory {
 
-	let schemeTransformer: ISchemeTransformer | null = null;
+	const schemeTransformer: ISchemeTransformer | null = null;
 
 	// Addressable instances
 	rpcProtocol.set(ExtHostContext.ExtHostLogService, extHostLogService);
@@ -188,7 +188,7 @@ export function createApiFactory(
 			},
 			registerTextEditorCommand(id: string, callback: (textEditor: vscode.TextEditor, edit: vscode.TextEditorEdit, ...args: any[]) => void, thisArg?: any): vscode.Disposable {
 				return extHostCommands.registerCommand(true, id, (...args: any[]): any => {
-					let activeTextEditor = extHostEditors.getActiveTextEditor();
+					const activeTextEditor = extHostEditors.getActiveTextEditor();
 					if (!activeTextEditor) {
 						console.warn('Cannot execute ' + id + ' because there is no active text editor.');
 						return undefined;
@@ -209,7 +209,7 @@ export function createApiFactory(
 			},
 			registerDiffInformationCommand: proposedApiFunction(extension, (id: string, callback: (diff: vscode.LineChange[], ...args: any[]) => any, thisArg?: any): vscode.Disposable => {
 				return extHostCommands.registerCommand(true, id, async (...args: any[]): Promise<any> => {
-					let activeTextEditor = extHostEditors.getActiveTextEditor();
+					const activeTextEditor = extHostEditors.getActiveTextEditor();
 					if (!activeTextEditor) {
 						console.warn('Cannot execute ' + id + ' because there is no active text editor.');
 						return undefined;
@@ -566,7 +566,7 @@ export function createApiFactory(
 			openTextDocument(uriOrFileNameOrOptions?: vscode.Uri | string | { language?: string; content?: string; }) {
 				let uriPromise: Thenable<URI>;
 
-				let options = uriOrFileNameOrOptions as { language?: string; content?: string; };
+				const options = uriOrFileNameOrOptions as { language?: string; content?: string; };
 				if (typeof uriOrFileNameOrOptions === 'string') {
 					uriPromise = Promise.resolve(URI.file(uriOrFileNameOrOptions));
 				} else if (uriOrFileNameOrOptions instanceof URI) {

src/vs/workbench/api/node/extHostApiCommands.ts

@@ -263,7 +263,7 @@ export class ExtHostApiCommands {
 	// --- command impl
 
 	private _register(id: string, handler: (...args: any[]) => any, description?: ICommandHandlerDescription): void {
-		let disposable = this._commands.registerCommand(false, id, handler, this, description);
+		const disposable = this._commands.registerCommand(false, id, handler, this, description);
 		this._disposables.push(disposable);
 	}
 
@@ -408,7 +408,7 @@ export class ExtHostApiCommands {
 	}
 
 	private _executeSelectionRangeProvider(resource: URI, positions: types.Position[]): Promise<vscode.SelectionRange[][]> {
-		let pos = positions.map(typeConverters.Position.from);
+		const pos = positions.map(typeConverters.Position.from);
 		const args = {
 			resource,
 			position: pos[0],
@@ -443,7 +443,7 @@ export class ExtHostApiCommands {
 			}
 			class MergedInfo extends types.SymbolInformation implements vscode.DocumentSymbol {
 				static to(symbol: modes.DocumentSymbol): MergedInfo {
-					let res = new MergedInfo(
+					const res = new MergedInfo(
 						symbol.name,
 						typeConverters.SymbolKind.to(symbol.kind),
 						symbol.containerName,

src/vs/workbench/api/node/extHostCommands.ts

@@ -154,7 +154,7 @@ export class ExtHostCommands implements ExtHostCommandsShape {
 		}
 
 		try {
-			let result = callback.apply(thisArg, args);
+			const result = callback.apply(thisArg, args);
 			return Promise.resolve(result);
 		} catch (err) {
 			this._logService.error(err, id);

src/vs/workbench/api/node/extHostComments.ts

@@ -344,7 +344,7 @@ export class ExtHostCommentThread implements vscode.CommentThread {
 	}
 
 	getComment(commentId: string): vscode.Comment | undefined {
-		let comments = this._comments.filter(comment => comment.commentId === commentId);
+		const comments = this._comments.filter(comment => comment.commentId === commentId);
 
 		if (comments && comments.length) {
 			return comments[0];
@@ -480,7 +480,7 @@ class ExtHostCommentControl implements vscode.CommentControl {
 	}
 
 	$onActiveCommentWidgetChange(commentThread: modes.CommentThread2, comment: modes.Comment | undefined, input: string) {
-		let extHostCommentThread = this._threads.get(commentThread.commentThreadHandle);
+		const extHostCommentThread = this._threads.get(commentThread.commentThreadHandle);
 
 		const extHostCommentWidget = new ExtHostCommentWidget(
 			this._proxy,

src/vs/workbench/api/node/extHostDebugService.ts

@@ -255,7 +255,7 @@ export class ExtHostDebugService implements ExtHostDebugServiceShape {
 			console.error('DebugConfigurationProvider.debugAdapterExecutable is deprecated and will be removed soon; please use DebugAdapterDescriptorFactory.createDebugAdapterDescriptor instead.');
 		}
 
-		let handle = this._configProviderHandleCounter++;
+		const handle = this._configProviderHandleCounter++;
 		this._configProviders.push({ type, handle, provider });
 
 		this._debugServiceProxy.$registerDebugConfigurationProvider(type,
@@ -286,7 +286,7 @@ export class ExtHostDebugService implements ExtHostDebugServiceShape {
 			throw new Error(`a DebugAdapterDescriptorFactory can only be registered once per a type.`);
 		}
 
-		let handle = this._adapterFactoryHandleCounter++;
+		const handle = this._adapterFactoryHandleCounter++;
 		this._adapterFactories.push({ type, handle, factory });
 
 		this._debugServiceProxy.$registerDebugAdapterDescriptorFactory(type, handle);
@@ -303,7 +303,7 @@ export class ExtHostDebugService implements ExtHostDebugServiceShape {
 			return new Disposable(() => { });
 		}
 
-		let handle = this._trackerFactoryHandleCounter++;
+		const handle = this._trackerFactoryHandleCounter++;
 		this._trackerFactories.push({ type, handle, factory });
 
 		this._debugServiceProxy.$registerDebugAdapterTrackerFactory(type, handle);
@@ -494,9 +494,9 @@ export class ExtHostDebugService implements ExtHostDebugServiceShape {
 
 	public $acceptBreakpointsDelta(delta: IBreakpointsDeltaDto): void {
 
-		let a: vscode.Breakpoint[] = [];
-		let r: vscode.Breakpoint[] = [];
-		let c: vscode.Breakpoint[] = [];
+		const a: vscode.Breakpoint[] = [];
+		const r: vscode.Breakpoint[] = [];
+		const c: vscode.Breakpoint[] = [];
 
 		if (delta.added) {
 			for (const bpd of delta.added) {
@@ -528,7 +528,7 @@ export class ExtHostDebugService implements ExtHostDebugServiceShape {
 
 		if (delta.changed) {
 			for (const bpd of delta.changed) {
-				let bp = this._breakpoints.get(bpd.id);
+				const bp = this._breakpoints.get(bpd.id);
 				if (bp) {
 					if (bp instanceof FunctionBreakpoint && bpd.type === 'function') {
 						const fbp = <any>bp;
@@ -554,7 +554,7 @@ export class ExtHostDebugService implements ExtHostDebugServiceShape {
 	}
 
 	public async $provideDebugConfigurations(configProviderHandle: number, folderUri: UriComponents | undefined): Promise<vscode.DebugConfiguration[]> {
-		let provider = this.getConfigProviderByHandle(configProviderHandle);
+		const provider = this.getConfigProviderByHandle(configProviderHandle);
 		if (!provider) {
 			return Promise.reject(new Error('no handler found'));
 		}
@@ -566,7 +566,7 @@ export class ExtHostDebugService implements ExtHostDebugServiceShape {
 	}
 
 	public async $resolveDebugConfiguration(configProviderHandle: number, folderUri: UriComponents | undefined, debugConfiguration: vscode.DebugConfiguration): Promise<vscode.DebugConfiguration> {
-		let provider = this.getConfigProviderByHandle(configProviderHandle);
+		const provider = this.getConfigProviderByHandle(configProviderHandle);
 		if (!provider) {
 			return Promise.reject(new Error('no handler found'));
 		}
@@ -579,7 +579,7 @@ export class ExtHostDebugService implements ExtHostDebugServiceShape {
 
 	// TODO@AW legacy
 	public async $legacyDebugAdapterExecutable(configProviderHandle: number, folderUri: UriComponents | undefined): Promise<IAdapterDescriptor> {
-		let provider = this.getConfigProviderByHandle(configProviderHandle);
+		const provider = this.getConfigProviderByHandle(configProviderHandle);
 		if (!provider) {
 			return Promise.reject(new Error('no handler found'));
 		}
@@ -591,7 +591,7 @@ export class ExtHostDebugService implements ExtHostDebugServiceShape {
 	}
 
 	public async $provideDebugAdapter(adapterProviderHandle: number, sessionDto: IDebugSessionDto): Promise<IAdapterDescriptor> {
-		let adapterProvider = this.getAdapterProviderByHandle(adapterProviderHandle);
+		const adapterProvider = this.getAdapterProviderByHandle(adapterProviderHandle);
 		if (!adapterProvider) {
 			return Promise.reject(new Error('no handler found'));
 		}

src/vs/workbench/api/node/extHostDiagnostics.ts

@@ -115,7 +115,7 @@ export class DiagnosticCollection implements vscode.DiagnosticCollection {
 		const entries: [URI, IMarkerData[]][] = [];
 		for (let uri of toSync) {
 			let marker: IMarkerData[] = [];
-			let diagnostics = this._data.get(uri.toString());
+			const diagnostics = this._data.get(uri.toString());
 			if (diagnostics) {
 
 				// no more than N diagnostics per file
@@ -170,14 +170,14 @@ export class DiagnosticCollection implements vscode.DiagnosticCollection {
 	forEach(callback: (uri: URI, diagnostics: vscode.Diagnostic[], collection: DiagnosticCollection) => any, thisArg?: any): void {
 		this._checkDisposed();
 		this._data.forEach((value, key) => {
-			let uri = URI.parse(key);
+			const uri = URI.parse(key);
 			callback.apply(thisArg, [uri, this.get(uri), this]);
 		});
 	}
 
 	get(uri: URI): vscode.Diagnostic[] {
 		this._checkDisposed();
-		let result = this._data.get(uri.toString());
+		const result = this._data.get(uri.toString());
 		if (Array.isArray(result)) {
 			return <vscode.Diagnostic[]>Object.freeze(result.slice(0));
 		}
@@ -224,8 +224,8 @@ export class ExtHostDiagnostics implements ExtHostDiagnosticsShape {
 	}
 
 	static _mapper(last: (vscode.Uri | string)[]): { uris: vscode.Uri[] } {
-		let uris: vscode.Uri[] = [];
-		let map = new Set<string>();
+		const uris: vscode.Uri[] = [];
+		const map = new Set<string>();
 		for (const uri of last) {
 			if (typeof uri === 'string') {
 				if (!map.has(uri)) {
@@ -285,8 +285,8 @@ export class ExtHostDiagnostics implements ExtHostDiagnosticsShape {
 		if (resource) {
 			return this._getDiagnostics(resource);
 		} else {
-			let index = new Map<string, number>();
-			let res: [vscode.Uri, vscode.Diagnostic[]][] = [];
+			const index = new Map<string, number>();
+			const res: [vscode.Uri, vscode.Diagnostic[]][] = [];
 			this._collections.forEach(collection => {
 				collection.forEach((uri, diagnostics) => {
 					let idx = index.get(uri.toString());

src/vs/workbench/api/node/extHostDocumentData.ts

@@ -105,7 +105,7 @@ export class ExtHostDocumentData extends MirrorTextModel {
 	}
 
 	private _getTextInRange(_range: vscode.Range): string {
-		let range = this._validateRange(_range);
+		const range = this._validateRange(_range);
 
 		if (range.isEmpty) {
 			return '';
@@ -115,7 +115,7 @@ export class ExtHostDocumentData extends MirrorTextModel {
 			return this._lines[range.start.line].substring(range.start.character, range.end.character);
 		}
 
-		let lineEnding = this._eol,
+		const lineEnding = this._eol,
 			startLineIndex = range.start.line,
 			endLineIndex = range.end.line,
 			resultLines: string[] = [];
@@ -178,9 +178,9 @@ export class ExtHostDocumentData extends MirrorTextModel {
 		offset = Math.max(0, offset);
 
 		this._ensureLineStarts();
-		let out = this._lineStarts!.getIndexOf(offset);
+		const out = this._lineStarts!.getIndexOf(offset);
 
-		let lineLength = this._lines[out.index].length;
+		const lineLength = this._lines[out.index].length;
 
 		// Ensure we return a valid position
 		return new Position(out.index, Math.min(out.remainder, lineLength));
@@ -193,8 +193,8 @@ export class ExtHostDocumentData extends MirrorTextModel {
 			throw new Error('Invalid argument');
 		}
 
-		let start = this._validatePosition(range.start);
-		let end = this._validatePosition(range.end);
+		const start = this._validatePosition(range.start);
+		const end = this._validatePosition(range.end);
 
 		if (start === range.start && end === range.end) {
 			return range;
@@ -221,7 +221,7 @@ export class ExtHostDocumentData extends MirrorTextModel {
 			hasChanged = true;
 		}
 		else {
-			let maxCharacter = this._lines[line].length;
+			const maxCharacter = this._lines[line].length;
 			if (character < 0) {
 				character = 0;
 				hasChanged = true;
@@ -239,7 +239,7 @@ export class ExtHostDocumentData extends MirrorTextModel {
 	}
 
 	private _getWordRangeAtPosition(_position: vscode.Position, regexp?: RegExp): vscode.Range | undefined {
-		let position = this._validatePosition(_position);
+		const position = this._validatePosition(_position);
 
 		if (!regexp) {
 			// use default when custom-regexp isn't provided
@@ -251,7 +251,7 @@ export class ExtHostDocumentData extends MirrorTextModel {
 			regexp = getWordDefinitionFor(this._languageId);
 		}
 
-		let wordAtText = getWordAtText(
+		const wordAtText = getWordAtText(
 			position.character + 1,
 			ensureValidWordDefinition(regexp),
 			this._lines[position.line],

src/vs/workbench/api/node/extHostDocumentSaveParticipant.ts

@@ -53,7 +53,7 @@ export class ExtHostDocumentSaveParticipant implements ExtHostDocumentSavePartic
 		const entries = this._callbacks.toArray();
 
 		let didTimeout = false;
-		let didTimeoutHandle = setTimeout(() => didTimeout = true, this._thresholds.timeout);
+		const didTimeoutHandle = setTimeout(() => didTimeout = true, this._thresholds.timeout);
 
 		const promise = sequence(entries.map(listener => {
 			return () => {

src/vs/workbench/api/node/extHostDocuments.ts

@@ -77,7 +77,7 @@ export class ExtHostDocuments implements ExtHostDocumentsShape {
 
 	public ensureDocumentData(uri: URI): Promise<ExtHostDocumentData> {
 
-		let cached = this._documentsAndEditors.getDocument(uri);
+		const cached = this._documentsAndEditors.getDocument(uri);
 		if (cached) {
 			return Promise.resolve(cached);
 		}

src/vs/workbench/api/node/extHostExtensionActivator.ts

@@ -238,14 +238,14 @@ export class ExtensionsActivator {
 		if (this._alreadyActivatedEvents[activationEvent]) {
 			return NO_OP_VOID_PROMISE;
 		}
-		let activateExtensions = this._registry.getExtensionDescriptionsForActivationEvent(activationEvent);
+		const activateExtensions = this._registry.getExtensionDescriptionsForActivationEvent(activationEvent);
 		return this._activateExtensions(activateExtensions.map(e => e.identifier), reason).then(() => {
 			this._alreadyActivatedEvents[activationEvent] = true;
 		});
 	}
 
 	public activateById(extensionId: ExtensionIdentifier, reason: ExtensionActivationReason): Promise<void> {
-		let desc = this._registry.getExtensionDescription(extensionId);
+		const desc = this._registry.getExtensionDescription(extensionId);
 		if (!desc) {
 			throw new Error('Extension `' + extensionId + '` is not known');
 		}
@@ -264,7 +264,7 @@ export class ExtensionsActivator {
 		}
 
 		const currentExtension = this._registry.getExtensionDescription(currentExtensionId)!;
-		let depIds = (typeof currentExtension.extensionDependencies === 'undefined' ? [] : currentExtension.extensionDependencies);
+		const depIds = (typeof currentExtension.extensionDependencies === 'undefined' ? [] : currentExtension.extensionDependencies);
 		let currentExtensionGetsGreenLight = true;
 
 		for (let j = 0, lenJ = depIds.length; j < lenJ; j++) {
@@ -330,7 +330,7 @@ export class ExtensionsActivator {
 			return Promise.resolve(undefined);
 		}
 
-		let greenMap: { [id: string]: ExtensionIdentifier; } = Object.create(null),
+		const greenMap: { [id: string]: ExtensionIdentifier; } = Object.create(null),
 			red: ExtensionIdentifier[] = [];
 
 		for (let i = 0, len = extensionIds.length; i < len; i++) {
@@ -345,7 +345,7 @@ export class ExtensionsActivator {
 			}
 		}
 
-		let green = Object.keys(greenMap).map(id => greenMap[id]);
+		const green = Object.keys(greenMap).map(id => greenMap[id]);
 
 		// console.log('greenExtensions: ', green.map(p => p.id));
 		// console.log('redExtensions: ', red.map(p => p.id));

src/vs/workbench/api/node/extHostExtensionService.ts

@@ -225,7 +225,7 @@ export class ExtHostExtensionService implements ExtHostExtensionServiceShape {
 
 			actualActivateExtension: async (extensionId: ExtensionIdentifier, reason: ExtensionActivationReason): Promise<ActivatedExtension> => {
 				if (hostExtensions.has(ExtensionIdentifier.toKey(extensionId))) {
-					let activationEvent = (reason instanceof ExtensionActivatedByEvent ? reason.activationEvent : null);
+					const activationEvent = (reason instanceof ExtensionActivatedByEvent ? reason.activationEvent : null);
 					await this._mainThreadExtensionsProxy.$activateExtension(extensionId, activationEvent);
 					return new HostExtension();
 				}
@@ -345,7 +345,7 @@ export class ExtHostExtensionService implements ExtHostExtensionServiceShape {
 			return result;
 		}
 
-		let extension = this._activator.getActivatedExtension(extensionId);
+		const extension = this._activator.getActivatedExtension(extensionId);
 		if (!extension) {
 			return result;
 		}
@@ -382,7 +382,7 @@ export class ExtHostExtensionService implements ExtHostExtensionServiceShape {
 		this._mainThreadExtensionsProxy.$onWillActivateExtension(extensionDescription.identifier);
 		return this._doActivateExtension(extensionDescription, reason).then((activatedExtension) => {
 			const activationTimes = activatedExtension.activationTimes;
-			let activationEvent = (reason instanceof ExtensionActivatedByEvent ? reason.activationEvent : null);
+			const activationEvent = (reason instanceof ExtensionActivatedByEvent ? reason.activationEvent : null);
 			this._mainThreadExtensionsProxy.$onDidActivateExtension(extensionDescription.identifier, activationTimes.startup, activationTimes.codeLoadingTime, activationTimes.activateCallTime, activationTimes.activateResolvedTime, activationEvent);
 			this._logExtensionActivationTimes(extensionDescription, reason, 'success', activationTimes);
 			return activatedExtension;
@@ -394,7 +394,7 @@ export class ExtHostExtensionService implements ExtHostExtensionServiceShape {
 	}
 
 	private _logExtensionActivationTimes(extensionDescription: IExtensionDescription, reason: ExtensionActivationReason, outcome: string, activationTimes?: ExtensionActivationTimes) {
-		let event = getTelemetryActivationEvent(extensionDescription, reason);
+		const event = getTelemetryActivationEvent(extensionDescription, reason);
 		/* __GDPR__
 			"extensionActivationTimes" : {
 				"${include}": [
@@ -412,7 +412,7 @@ export class ExtHostExtensionService implements ExtHostExtensionServiceShape {
 	}
 
 	private _doActivateExtension(extensionDescription: IExtensionDescription, reason: ExtensionActivationReason): Promise<ActivatedExtension> {
-		let event = getTelemetryActivationEvent(extensionDescription, reason);
+		const event = getTelemetryActivationEvent(extensionDescription, reason);
 		/* __GDPR__
 			"activatePlugin" : {
 				"${include}": [
@@ -439,8 +439,8 @@ export class ExtHostExtensionService implements ExtHostExtensionServiceShape {
 
 	private _loadExtensionContext(extensionDescription: IExtensionDescription): Promise<IExtensionContext> {
 
-		let globalState = new ExtensionMemento(extensionDescription.identifier.value, true, this._storage);
-		let workspaceState = new ExtensionMemento(extensionDescription.identifier.value, false, this._storage);
+		const globalState = new ExtensionMemento(extensionDescription.identifier.value, true, this._storage);
+		const workspaceState = new ExtensionMemento(extensionDescription.identifier.value, false, this._storage);
 
 		this._extHostLogService.trace(`ExtensionService#loadExtensionContext ${extensionDescription.identifier.value}`);
 		return Promise.all([
@@ -763,7 +763,7 @@ export class ExtHostExtensionService implements ExtHostExtensionServiceShape {
 	}
 
 	public async $test_down(size: number): Promise<Buffer> {
-		let b = Buffer.alloc(size, Math.random() % 256);
+		const b = Buffer.alloc(size, Math.random() % 256);
 		return b;
 	}
 
@@ -799,7 +799,7 @@ function getTelemetryActivationEvent(extensionDescription: IExtensionDescription
 			"reason": { "classification": "SystemMetaData", "purpose": "FeatureInsight" }
 		}
 	*/
-	let event = {
+	const event = {
 		id: extensionDescription.identifier.value,
 		name: extensionDescription.name,
 		extensionVersion: extensionDescription.version,

src/vs/workbench/api/node/extHostFileSystem.ts

@@ -28,7 +28,7 @@ class FsLinkProvider {
 	}
 
 	delete(scheme: string): void {
-		let idx = this._schemes.indexOf(scheme);
+		const idx = this._schemes.indexOf(scheme);
 		if (idx >= 0) {
 			this._schemes.splice(idx, 1);
 			this._stateMachine = undefined;
@@ -94,7 +94,7 @@ class FsLinkProvider {
 		}, this._stateMachine);
 
 		for (const link of links) {
-			let docLink = typeConverter.DocumentLink.to(link);
+			const docLink = typeConverter.DocumentLink.to(link);
 			if (docLink.target) {
 				result.push(docLink);
 			}
@@ -172,7 +172,7 @@ export class ExtHostFileSystem implements ExtHostFileSystemShape {
 		this._proxy.$registerFileSystemProvider(handle, scheme, capabilites);
 
 		const subscription = provider.onDidChangeFile(event => {
-			let mapped: IFileChangeDto[] = [];
+			const mapped: IFileChangeDto[] = [];
 			for (const e of event) {
 				let { uri: resource, type } = e;
 				if (resource.scheme !== scheme) {
@@ -260,12 +260,12 @@ export class ExtHostFileSystem implements ExtHostFileSystemShape {
 	}
 
 	$watch(handle: number, session: number, resource: UriComponents, opts: files.IWatchOptions): void {
-		let subscription = this.getProvider(handle).watch(URI.revive(resource), opts);
+		const subscription = this.getProvider(handle).watch(URI.revive(resource), opts);
 		this._watches.set(session, subscription);
 	}
 
 	$unwatch(_handle: number, session: number): void {
-		let subscription = this._watches.get(session);
+		const subscription = this._watches.get(session);
 		if (subscription) {
 			subscription.dispose();
 			this._watches.delete(session);

src/vs/workbench/api/node/extHostFileSystemEventService.ts

@@ -49,10 +49,10 @@ class FileSystemWatcher implements vscode.FileSystemWatcher {
 
 		const parsedPattern = parse(globPattern);
 
-		let subscription = dispatcher(events => {
+		const subscription = dispatcher(events => {
 			if (!ignoreCreateEvents) {
 				for (let created of events.created) {
-					let uri = URI.revive(created);
+					const uri = URI.revive(created);
 					if (parsedPattern(uri.fsPath)) {
 						this._onDidCreate.fire(uri);
 					}
@@ -60,7 +60,7 @@ class FileSystemWatcher implements vscode.FileSystemWatcher {
 			}
 			if (!ignoreChangeEvents) {
 				for (let changed of events.changed) {
-					let uri = URI.revive(changed);
+					const uri = URI.revive(changed);
 					if (parsedPattern(uri.fsPath)) {
 						this._onDidChange.fire(uri);
 					}
@@ -68,7 +68,7 @@ class FileSystemWatcher implements vscode.FileSystemWatcher {
 			}
 			if (!ignoreDeleteEvents) {
 				for (let deleted of events.deleted) {
-					let uri = URI.revive(deleted);
+					const uri = URI.revive(deleted);
 					if (parsedPattern(uri.fsPath)) {
 						this._onDidDelete.fire(uri);
 					}
@@ -169,7 +169,7 @@ export class ExtHostFileSystemEventService implements ExtHostFileSystemEventServ
 			}
 			// flatten all WorkspaceEdits collected via waitUntil-call
 			// and apply them in one go.
-			let allEdits = new Array<Array<ResourceFileEditDto | ResourceTextEditDto>>();
+			const allEdits = new Array<Array<ResourceFileEditDto | ResourceTextEditDto>>();
 			for (let edit of edits) {
 				if (edit) { // sparse array
 					let { edits } = typeConverter.WorkspaceEdit.from(edit, this._extHostDocumentsAndEditors);

src/vs/workbench/api/node/extHostLanguageFeatures.ts

@@ -65,10 +65,10 @@ class DocumentSymbolAdapter {
 			}
 			return res;
 		});
-		let res: modes.DocumentSymbol[] = [];
-		let parentStack: modes.DocumentSymbol[] = [];
+		const res: modes.DocumentSymbol[] = [];
+		const parentStack: modes.DocumentSymbol[] = [];
 		for (const info of infos) {
-			let element = <modes.DocumentSymbol>{
+			const element = <modes.DocumentSymbol>{
 				name: info.name || '!!MISSING: name!!',
 				kind: typeConvert.SymbolKind.from(info.kind),
 				containerName: info.containerName,
@@ -83,7 +83,7 @@ class DocumentSymbolAdapter {
 					res.push(element);
 					break;
 				}
-				let parent = parentStack[parentStack.length - 1];
+				const parent = parentStack[parentStack.length - 1];
 				if (EditorRange.containsRange(parent.range, element.range) && !EditorRange.equalsRange(parent.range, element.range)) {
 					parent.children.push(element);
 					parentStack.push(element);
@@ -111,7 +111,7 @@ class CodeLensAdapter {
 		const doc = this._documents.getDocument(resource);
 
 		return asPromise(() => this._provider.provideCodeLenses(doc, token)).then(lenses => {
-			let result: CodeLensDto[] = [];
+			const result: CodeLensDto[] = [];
 			if (isNonEmptyArray(lenses)) {
 				for (const lens of lenses) {
 					const id = this._heapService.keep(lens);
@@ -206,7 +206,7 @@ class DefinitionAdapter {
 
 	provideDefinition(resource: URI, position: IPosition, token: CancellationToken): Promise<modes.LocationLink[]> {
 		const doc = this._documents.getDocument(resource);
-		let pos = typeConvert.Position.to(position);
+		const pos = typeConvert.Position.to(position);
 		return asPromise(() => this._provider.provideDefinition(doc, pos, token)).then(convertToLocationLinks);
 	}
 }
@@ -220,7 +220,7 @@ class DeclarationAdapter {
 
 	provideDeclaration(resource: URI, position: IPosition, token: CancellationToken): Promise<modes.LocationLink[]> {
 		const doc = this._documents.getDocument(resource);
-		let pos = typeConvert.Position.to(position);
+		const pos = typeConvert.Position.to(position);
 		return asPromise(() => this._provider.provideDeclaration(doc, pos, token)).then(convertToLocationLinks);
 	}
 }
@@ -234,7 +234,7 @@ class ImplementationAdapter {
 
 	provideImplementation(resource: URI, position: IPosition, token: CancellationToken): Promise<modes.LocationLink[]> {
 		const doc = this._documents.getDocument(resource);
-		let pos = typeConvert.Position.to(position);
+		const pos = typeConvert.Position.to(position);
 		return asPromise(() => this._provider.provideImplementation(doc, pos, token)).then(convertToLocationLinks);
 	}
 }
@@ -263,7 +263,7 @@ class HoverAdapter {
 	public provideHover(resource: URI, position: IPosition, token: CancellationToken): Promise<modes.Hover | undefined> {
 
 		const doc = this._documents.getDocument(resource);
-		let pos = typeConvert.Position.to(position);
+		const pos = typeConvert.Position.to(position);
 
 		return asPromise(() => this._provider.provideHover(doc, pos, token)).then(value => {
 			if (!value || isFalsyOrEmpty(value.contents)) {
@@ -291,7 +291,7 @@ class DocumentHighlightAdapter {
 	provideDocumentHighlights(resource: URI, position: IPosition, token: CancellationToken): Promise<modes.DocumentHighlight[] | undefined> {
 
 		const doc = this._documents.getDocument(resource);
-		let pos = typeConvert.Position.to(position);
+		const pos = typeConvert.Position.to(position);
 
 		return asPromise(() => this._provider.provideDocumentHighlights(doc, pos, token)).then(value => {
 			if (Array.isArray(value)) {
@@ -311,7 +311,7 @@ class ReferenceAdapter {
 
 	provideReferences(resource: URI, position: IPosition, context: modes.ReferenceContext, token: CancellationToken): Promise<modes.Location[] | undefined> {
 		const doc = this._documents.getDocument(resource);
-		let pos = typeConvert.Position.to(position);
+		const pos = typeConvert.Position.to(position);
 
 		return asPromise(() => this._provider.provideReferences(doc, pos, context, token)).then(value => {
 			if (Array.isArray(value)) {
@@ -546,7 +546,7 @@ class RenameAdapter {
 	provideRenameEdits(resource: URI, position: IPosition, newName: string, token: CancellationToken): Promise<WorkspaceEditDto | undefined> {
 
 		const doc = this._documents.getDocument(resource);
-		let pos = typeConvert.Position.to(position);
+		const pos = typeConvert.Position.to(position);
 
 		return asPromise(() => this._provider.provideRenameEdits(doc, pos, newName, token)).then(value => {
 			if (!value) {
@@ -554,7 +554,7 @@ class RenameAdapter {
 			}
 			return typeConvert.WorkspaceEdit.from(value);
 		}, err => {
-			let rejectReason = RenameAdapter._asMessage(err);
+			const rejectReason = RenameAdapter._asMessage(err);
 			if (rejectReason) {
 				return <WorkspaceEditDto>{ rejectReason, edits: undefined! };
 			} else {
@@ -570,7 +570,7 @@ class RenameAdapter {
 		}
 
 		const doc = this._documents.getDocument(resource);
-		let pos = typeConvert.Position.to(position);
+		const pos = typeConvert.Position.to(position);
 
 		return asPromise(() => this._provider.prepareRename!(doc, pos, token)).then(rangeOrLocation => {
 
@@ -594,7 +594,7 @@ class RenameAdapter {
 			}
 			return { range: typeConvert.Range.from(range), text };
 		}, err => {
-			let rejectReason = RenameAdapter._asMessage(err);
+			const rejectReason = RenameAdapter._asMessage(err);
 			if (rejectReason) {
 				return <modes.RenameLocation & modes.Rejection>{ rejectReason, range: undefined!, text: undefined! };
 			} else {
@@ -832,8 +832,8 @@ class LinkProviderAdapter {
 			}
 			const result: LinkDto[] = [];
 			for (const link of links) {
-				let data = typeConvert.DocumentLink.from(link);
-				let id = this._heapService.keep(link);
+				const data = typeConvert.DocumentLink.from(link);
+				const id = this._heapService.keep(link);
 				result.push(ObjectIdentifier.mixin(data, id));
 			}
 			return result;
@@ -936,7 +936,7 @@ class SelectionRangeAdapter {
 				return [];
 			}
 
-			let allResults: modes.SelectionRange[][] = [];
+			const allResults: modes.SelectionRange[][] = [];
 			for (let i = 0; i < positions.length; i++) {
 				const oneResult: modes.SelectionRange[] = [];
 				allResults.push(oneResult);
@@ -1065,7 +1065,7 @@ export class ExtHostLanguageFeatures implements ExtHostLanguageFeaturesShape {
 				t1 = Date.now();
 				this._logService.trace(`[${data.extension.identifier.value}] INVOKE provider '${(ctor as any).name}'`);
 			}
-			let p = callback(data.adapter, data.extension);
+			const p = callback(data.adapter, data.extension);
 			const extension = data.extension;
 			if (extension) {
 				Promise.resolve(p).then(

src/vs/workbench/api/node/extHostMessageService.ts

@@ -24,7 +24,7 @@ export class ExtHostMessageService {
 	showMessage(extension: IExtensionDescription, severity: Severity, message: string, optionsOrFirstItem: vscode.MessageOptions | vscode.MessageItem, rest: vscode.MessageItem[]): Promise<vscode.MessageItem | undefined>;
 	showMessage(extension: IExtensionDescription, severity: Severity, message: string, optionsOrFirstItem: vscode.MessageOptions | string | vscode.MessageItem, rest: (string | vscode.MessageItem)[]): Promise<string | vscode.MessageItem | undefined> {
 
-		let options: MainThreadMessageOptions = { extension };
+		const options: MainThreadMessageOptions = { extension };
 		let items: (string | vscode.MessageItem)[];
 
 		if (typeof optionsOrFirstItem === 'string' || isMessageItem(optionsOrFirstItem)) {
@@ -37,7 +37,7 @@ export class ExtHostMessageService {
 		const commands: { title: string; isCloseAffordance: boolean; handle: number; }[] = [];
 
 		for (let handle = 0; handle < items.length; handle++) {
-			let command = items[handle];
+			const command = items[handle];
 			if (typeof command === 'string') {
 				commands.push({ title: command, handle, isCloseAffordance: false });
 			} else if (typeof command === 'object') {

src/vs/workbench/api/node/extHostQuickOpen.ts

@@ -68,10 +68,10 @@ export class ExtHostQuickOpen implements ExtHostQuickOpenShape {
 
 			return itemsPromise.then(items => {
 
-				let pickItems: TransferQuickPickItems[] = [];
+				const pickItems: TransferQuickPickItems[] = [];
 				for (let handle = 0; handle < items.length; handle++) {
 
-					let item = items[handle];
+					const item = items[handle];
 					let label: string;
 					let description: string | undefined;
 					let detail: string | undefined;

src/vs/workbench/api/node/extHostSearch.fileIndex.ts

@@ -116,7 +116,7 @@ export class FileIndexSearchEngine {
 	}
 
 	private searchInFolder(fq: IFolderQuery<URI>, onResult: (match: IInternalFileMatch) => void): Promise<IFileIndexProviderStats> {
-		let cancellation = new CancellationTokenSource();
+		const cancellation = new CancellationTokenSource();
 		return new Promise((resolve, reject) => {
 			const options = this.getSearchOptionsForFolder(fq);
 			const tree = this.initDirectoryTree();
@@ -511,10 +511,10 @@ export class FileIndexSearchManager {
 				}
 
 				// Pattern match on results
-				let results: IInternalFileMatch[] = [];
+				const results: IInternalFileMatch[] = [];
 				const normalizedSearchValueLowercase = strings.stripWildcards(searchValue).toLowerCase();
 				for (let i = 0; i < complete.results.length; i++) {
-					let entry = complete.results[i];
+					const entry = complete.results[i];
 
 					// Check if this entry is a match for the search value
 					if (!strings.fuzzyContains(entry.relativePath!, normalizedSearchValueLowercase)) {

src/vs/workbench/api/node/extHostStatusBar.ts

@@ -139,7 +139,7 @@ class StatusBarMessage {
 		this._update();
 
 		return new Disposable(() => {
-			let idx = this._messages.indexOf(data);
+			const idx = this._messages.indexOf(data);
 			if (idx >= 0) {
 				this._messages.splice(idx, 1);
 				this._update();
@@ -173,7 +173,7 @@ export class ExtHostStatusBar {
 
 	setStatusBarMessage(text: string, timeoutOrThenable?: number | Thenable<any>): Disposable {
 
-		let d = this._statusMessage.setMessage(text);
+		const d = this._statusMessage.setMessage(text);
 		let handle: any;
 
 		if (typeof timeoutOrThenable === 'number') {

src/vs/workbench/api/node/extHostTask.ts

@@ -75,14 +75,14 @@ namespace ProcessExecutionOptionsDTO {
 
 namespace ProcessExecutionDTO {
 	export function is(value: ShellExecutionDTO | ProcessExecutionDTO): value is ProcessExecutionDTO {
-		let candidate = value as ProcessExecutionDTO;
+		const candidate = value as ProcessExecutionDTO;
 		return candidate && !!candidate.process;
 	}
 	export function from(value: vscode.ProcessExecution): ProcessExecutionDTO {
 		if (value === undefined || value === null) {
 			return undefined;
 		}
-		let result: ProcessExecutionDTO = {
+		const result: ProcessExecutionDTO = {
 			process: value.process,
 			args: value.args
 		};
@@ -116,14 +116,14 @@ namespace ShellExecutionOptionsDTO {
 
 namespace ShellExecutionDTO {
 	export function is(value: ShellExecutionDTO | ProcessExecutionDTO): value is ShellExecutionDTO {
-		let candidate = value as ShellExecutionDTO;
+		const candidate = value as ShellExecutionDTO;
 		return candidate && (!!candidate.commandLine || !!candidate.command);
 	}
 	export function from(value: vscode.ShellExecution): ShellExecutionDTO {
 		if (value === undefined || value === null) {
 			return undefined;
 		}
-		let result: ShellExecutionDTO = {
+		const result: ShellExecutionDTO = {
 		};
 		if (value.commandLine !== undefined) {
 			result.commandLine = value.commandLine;
@@ -167,9 +167,9 @@ namespace TaskDTO {
 		if (tasks === undefined || tasks === null) {
 			return [];
 		}
-		let result: TaskDTO[] = [];
+		const result: TaskDTO[] = [];
 		for (let task of tasks) {
-			let converted = from(task, extension);
+			const converted = from(task, extension);
 			if (converted) {
 				result.push(converted);
 			}
@@ -187,7 +187,7 @@ namespace TaskDTO {
 		} else if (value.execution instanceof types.ShellExecution) {
 			execution = ShellExecutionDTO.from(value.execution);
 		}
-		let definition: TaskDefinitionDTO = TaskDefinitionDTO.from(value.definition);
+		const definition: TaskDefinitionDTO = TaskDefinitionDTO.from(value.definition);
 		let scope: number | UriComponents;
 		if (value.scope) {
 			if (typeof value.scope === 'number') {
@@ -202,8 +202,8 @@ namespace TaskDTO {
 		if (!definition || !scope) {
 			return undefined;
 		}
-		let group = (value.group as types.TaskGroup) ? (value.group as types.TaskGroup).id : undefined;
-		let result: TaskDTO = {
+		const group = (value.group as types.TaskGroup) ? (value.group as types.TaskGroup).id : undefined;
+		const result: TaskDTO = {
 			_id: (value as types.Task)._id,
 			definition,
 			name: value.name,
@@ -232,7 +232,7 @@ namespace TaskDTO {
 		} else if (ShellExecutionDTO.is(value.execution)) {
 			execution = ShellExecutionDTO.to(value.execution);
 		}
-		let definition: vscode.TaskDefinition = TaskDefinitionDTO.to(value.definition);
+		const definition: vscode.TaskDefinition = TaskDefinitionDTO.to(value.definition);
 		let scope: vscode.TaskScope.Global | vscode.TaskScope.Workspace | vscode.WorkspaceFolder | undefined;
 		if (value.source) {
 			if (value.source.scope !== undefined) {
@@ -248,7 +248,7 @@ namespace TaskDTO {
 		if (!definition || !scope) {
 			return undefined;
 		}
-		let result = new types.Task(definition, scope, value.name, value.source.label, execution, value.problemMatchers);
+		const result = new types.Task(definition, scope, value.name, value.source.label, execution, value.problemMatchers);
 		if (value.isBackground !== undefined) {
 			result.isBackground = value.isBackground;
 		}
@@ -345,7 +345,7 @@ export class ExtHostTask implements ExtHostTaskShape {
 		if (!provider) {
 			return new types.Disposable(() => { });
 		}
-		let handle = this.nextHandle();
+		const handle = this.nextHandle();
 		this._handlers.set(handle, { provider, extension });
 		this._proxy.$registerTaskProvider(handle);
 		return new types.Disposable(() => {
@@ -360,9 +360,9 @@ export class ExtHostTask implements ExtHostTaskShape {
 
 	public fetchTasks(filter?: vscode.TaskFilter): Promise<vscode.Task[]> {
 		return this._proxy.$fetchTasks(TaskFilterDTO.from(filter)).then(async (values) => {
-			let result: vscode.Task[] = [];
+			const result: vscode.Task[] = [];
 			for (let value of values) {
-				let task = await TaskDTO.to(value, this._workspaceProvider);
+				const task = await TaskDTO.to(value, this._workspaceProvider);
 				if (task) {
 					result.push(task);
 				}
@@ -372,12 +372,12 @@ export class ExtHostTask implements ExtHostTaskShape {
 	}
 
 	public async executeTask(extension: IExtensionDescription, task: vscode.Task): Promise<vscode.TaskExecution> {
-		let tTask = (task as types.Task);
+		const tTask = (task as types.Task);
 		// We have a preserved ID. So the task didn't change.
 		if (tTask._id !== undefined) {
 			return this._proxy.$executeTask(TaskHandleDTO.from(tTask)).then(value => this.getTaskExecution(value, task));
 		} else {
-			let dto = TaskDTO.from(task, extension);
+			const dto = TaskDTO.from(task, extension);
 			if (dto === undefined) {
 				return Promise.reject(new Error('Task is not valid'));
 			}
@@ -386,7 +386,7 @@ export class ExtHostTask implements ExtHostTaskShape {
 	}
 
 	public get taskExecutions(): vscode.TaskExecution[] {
-		let result: vscode.TaskExecution[] = [];
+		const result: vscode.TaskExecution[] = [];
 		this._taskExecutions.forEach(value => result.push(value));
 		return result;
 	}
@@ -449,12 +449,12 @@ export class ExtHostTask implements ExtHostTaskShape {
 	}
 
 	public $provideTasks(handle: number, validTypes: { [key: string]: boolean; }): Thenable<TaskSetDTO> {
-		let handler = this._handlers.get(handle);
+		const handler = this._handlers.get(handle);
 		if (!handler) {
 			return Promise.reject(new Error('no handler found'));
 		}
 		return asPromise(() => handler.provider.provideTasks(CancellationToken.None)).then(value => {
-			let sanitized: vscode.Task[] = [];
+			const sanitized: vscode.Task[] = [];
 			for (let task of value) {
 				if (task.definition && validTypes[task.definition.type] === true) {
 					sanitized.push(task);
@@ -472,15 +472,15 @@ export class ExtHostTask implements ExtHostTaskShape {
 
 	public async $resolveVariables(uriComponents: UriComponents, toResolve: { process?: { name: string; cwd?: string; path?: string }, variables: string[] }): Promise<{ process?: string, variables: { [key: string]: string; } }> {
 		const configProvider = await this._configurationService.getConfigProvider();
-		let uri: URI = URI.revive(uriComponents);
-		let result = {
+		const uri: URI = URI.revive(uriComponents);
+		const result = {
 			process: undefined as string,
 			variables: Object.create(null)
 		};
-		let workspaceFolder = await this._workspaceProvider.resolveWorkspaceFolder(uri);
+		const workspaceFolder = await this._workspaceProvider.resolveWorkspaceFolder(uri);
 		const workspaceFolders = await this._workspaceProvider.getWorkspaceFolders2();
-		let resolver = new ExtHostVariableResolverService(workspaceFolders, this._editorService, configProvider);
-		let ws: IWorkspaceFolder = {
+		const resolver = new ExtHostVariableResolverService(workspaceFolders, this._editorService, configProvider);
+		const ws: IWorkspaceFolder = {
 			uri: workspaceFolder.uri,
 			name: workspaceFolder.name,
 			index: workspaceFolder.index,

src/vs/workbench/api/node/extHostTextEditor.ts

@@ -106,7 +106,7 @@ export class TextEditorEdit {
 	}
 
 	private _pushEdit(range: Range, text: string | null, forceMoveMarkers: boolean): void {
-		let validRange = this._document.validateRange(range);
+		const validRange = this._document.validateRange(range);
 		this._collectedEdits.push({
 			range: validRange,
 			text: text,
@@ -170,11 +170,11 @@ export class ExtHostTextEditorOptions implements vscode.TextEditorOptions {
 			return 'auto';
 		}
 		if (typeof value === 'number') {
-			let r = Math.floor(value);
+			const r = Math.floor(value);
 			return (r > 0 ? r : null);
 		}
 		if (typeof value === 'string') {
-			let r = parseInt(value, 10);
+			const r = parseInt(value, 10);
 			if (isNaN(r)) {
 				return null;
 			}
@@ -184,7 +184,7 @@ export class ExtHostTextEditorOptions implements vscode.TextEditorOptions {
 	}
 
 	public set tabSize(value: number | string) {
-		let tabSize = this._validateTabSize(value);
+		const tabSize = this._validateTabSize(value);
 		if (tabSize === null) {
 			// ignore invalid call
 			return;
@@ -211,11 +211,11 @@ export class ExtHostTextEditorOptions implements vscode.TextEditorOptions {
 			return 'tabSize';
 		}
 		if (typeof value === 'number') {
-			let r = Math.floor(value);
+			const r = Math.floor(value);
 			return (r > 0 ? r : null);
 		}
 		if (typeof value === 'string') {
-			let r = parseInt(value, 10);
+			const r = parseInt(value, 10);
 			if (isNaN(r)) {
 				return null;
 			}
@@ -225,7 +225,7 @@ export class ExtHostTextEditorOptions implements vscode.TextEditorOptions {
 	}
 
 	public set indentSize(value: number | string) {
-		let indentSize = this._validateIndentSize(value);
+		const indentSize = this._validateIndentSize(value);
 		if (indentSize === null) {
 			// ignore invalid call
 			return;
@@ -255,7 +255,7 @@ export class ExtHostTextEditorOptions implements vscode.TextEditorOptions {
 	}
 
 	public set insertSpaces(value: boolean | string) {
-		let insertSpaces = this._validateInsertSpaces(value);
+		const insertSpaces = this._validateInsertSpaces(value);
 		if (typeof insertSpaces === 'boolean') {
 			if (this._insertSpaces === insertSpaces) {
 				// nothing to do
@@ -300,11 +300,11 @@ export class ExtHostTextEditorOptions implements vscode.TextEditorOptions {
 	}
 
 	public assign(newOptions: vscode.TextEditorOptions) {
-		let bulkConfigurationUpdate: ITextEditorConfigurationUpdate = {};
+		const bulkConfigurationUpdate: ITextEditorConfigurationUpdate = {};
 		let hasUpdate = false;
 
 		if (typeof newOptions.tabSize !== 'undefined') {
-			let tabSize = this._validateTabSize(newOptions.tabSize);
+			const tabSize = this._validateTabSize(newOptions.tabSize);
 			if (tabSize === 'auto') {
 				hasUpdate = true;
 				bulkConfigurationUpdate.tabSize = tabSize;
@@ -317,7 +317,7 @@ export class ExtHostTextEditorOptions implements vscode.TextEditorOptions {
 		}
 
 		// if (typeof newOptions.indentSize !== 'undefined') {
-		// 	let indentSize = this._validateIndentSize(newOptions.indentSize);
+		// 	const indentSize = this._validateIndentSize(newOptions.indentSize);
 		// 	if (indentSize === 'tabSize') {
 		// 		hasUpdate = true;
 		// 		bulkConfigurationUpdate.indentSize = indentSize;
@@ -330,7 +330,7 @@ export class ExtHostTextEditorOptions implements vscode.TextEditorOptions {
 		// }
 
 		if (typeof newOptions.insertSpaces !== 'undefined') {
-			let insertSpaces = this._validateInsertSpaces(newOptions.insertSpaces);
+			const insertSpaces = this._validateInsertSpaces(newOptions.insertSpaces);
 			if (insertSpaces === 'auto') {
 				hasUpdate = true;
 				bulkConfigurationUpdate.insertSpaces = insertSpaces;
@@ -510,7 +510,7 @@ export class ExtHostTextEditor implements vscode.TextEditor {
 						TypeConverters.fromRangeOrRangeWithMessage(ranges)
 					);
 				} else {
-					let _ranges: number[] = new Array<number>(4 * ranges.length);
+					const _ranges: number[] = new Array<number>(4 * ranges.length);
 					for (let i = 0, len = ranges.length; i < len; i++) {
 						const range = ranges[i];
 						_ranges[4 * i] = range.start.line + 1;
@@ -539,7 +539,7 @@ export class ExtHostTextEditor implements vscode.TextEditor {
 	}
 
 	private _trySetSelection(): Promise<vscode.TextEditor | null | undefined> {
-		let selection = this._selections.map(TypeConverters.Selection.from);
+		const selection = this._selections.map(TypeConverters.Selection.from);
 		return this._runOnProxy(() => this._proxy.$trySetSelections(this._id, selection));
 	}
 
@@ -554,13 +554,13 @@ export class ExtHostTextEditor implements vscode.TextEditor {
 		if (this._disposed) {
 			return Promise.reject(new Error('TextEditor#edit not possible on closed editors'));
 		}
-		let edit = new TextEditorEdit(this._documentData.document, options);
+		const edit = new TextEditorEdit(this._documentData.document, options);
 		callback(edit);
 		return this._applyEdit(edit);
 	}
 
 	private _applyEdit(editBuilder: TextEditorEdit): Promise<boolean> {
-		let editData = editBuilder.finalize();
+		const editData = editBuilder.finalize();
 
 		// return when there is nothing to do
 		if (editData.edits.length === 0 && !editData.setEndOfLine) {
@@ -568,7 +568,7 @@ export class ExtHostTextEditor implements vscode.TextEditor {
 		}
 
 		// check that the edits are not overlapping (i.e. illegal)
-		let editRanges = editData.edits.map(edit => edit.range);
+		const editRanges = editData.edits.map(edit => edit.range);
 
 		// sort ascending (by end and then by start)
 		editRanges.sort((a, b) => {

src/vs/workbench/api/node/extHostTextEditors.ts

@@ -75,7 +75,7 @@ export class ExtHostEditors implements ExtHostEditorsShape {
 		}
 
 		return this._proxy.$tryShowTextDocument(document.uri, options).then(id => {
-			let editor = this._extHostDocumentsAndEditors.getEditor(id);
+			const editor = this._extHostDocumentsAndEditors.getEditor(id);
 			if (editor) {
 				return editor;
 			} else {

src/vs/workbench/api/node/extHostTreeViews.ts

@@ -366,7 +366,7 @@ class ExtHostTreeView<T> extends Disposable {
 	private getHandlesToRefresh(elements: T[]): TreeItemHandle[] {
 		const elementsToUpdate = new Set<TreeItemHandle>();
 		for (const element of elements) {
-			let elementNode = this.nodes.get(element);
+			const elementNode = this.nodes.get(element);
 			if (elementNode && !elementsToUpdate.has(elementNode.item.handle)) {
 				// check if an ancestor of extElement is already in the elements to update list
 				let currentNode = elementNode;
@@ -384,7 +384,7 @@ class ExtHostTreeView<T> extends Disposable {
 		// Take only top level elements
 		elementsToUpdate.forEach((handle) => {
 			const element = this.elements.get(handle);
-			let node = this.nodes.get(element);
+			const node = this.nodes.get(element);
 			if (node && (!node.parent || !elementsToUpdate.has(node.parent.item.handle))) {
 				handlesToUpdate.push(handle);
 			}
@@ -553,7 +553,7 @@ class ExtHostTreeView<T> extends Disposable {
 
 	private clearChildren(parentElement?: T): void {
 		if (parentElement) {
-			let node = this.nodes.get(parentElement);
+			const node = this.nodes.get(parentElement);
 			if (node.children) {
 				for (const child of node.children) {
 					const childEleement = this.elements.get(child.item.handle);
@@ -569,7 +569,7 @@ class ExtHostTreeView<T> extends Disposable {
 	}
 
 	private clear(element: T): void {
-		let node = this.nodes.get(element);
+		const node = this.nodes.get(element);
 		if (node.children) {
 			for (const child of node.children) {
 				const childEleement = this.elements.get(child.item.handle);

src/vs/workbench/api/node/extHostTypeConverters.ts

@@ -236,7 +236,7 @@ export namespace MarkdownString {
 		const resUris: { [href: string]: UriComponents } = Object.create(null);
 		res.uris = resUris;
 
-		let renderer = new marked.Renderer();
+		const renderer = new marked.Renderer();
 		renderer.image = renderer.link = (href: string): string => {
 			try {
 				let uri = URI.parse(href, true);
@@ -267,7 +267,7 @@ export namespace MarkdownString {
 		}
 		data = cloneAndChange(data, value => {
 			if (value instanceof URI) {
-				let key = `__uri_${Math.random().toString(16).slice(2, 8)}`;
+				const key = `__uri_${Math.random().toString(16).slice(2, 8)}`;
 				bucket[key] = value;
 				return key;
 			} else {

src/vs/workbench/api/node/extHostTypes.ts

@@ -66,7 +66,7 @@ export class Position {
 		}
 		let result = positions[0];
 		for (let i = 1; i < positions.length; i++) {
-			let p = positions[i];
+			const p = positions[i];
 			if (p.isBefore(result!)) {
 				result = p;
 			}
@@ -80,7 +80,7 @@ export class Position {
 		}
 		let result = positions[0];
 		for (let i = 1; i < positions.length; i++) {
-			let p = positions[i];
+			const p = positions[i];
 			if (p.isAfter(result!)) {
 				result = p;
 			}
@@ -303,8 +303,8 @@ export class Range {
 	}
 
 	intersection(other: Range): Range | undefined {
-		let start = Position.Max(other.start, this._start);
-		let end = Position.Min(other.end, this._end);
+		const start = Position.Max(other.start, this._start);
+		const end = Position.Min(other.end, this._end);
 		if (start.isAfter(end)) {
 			// this happens when there is no overlap:
 			// |-----|
@@ -320,8 +320,8 @@ export class Range {
 		} else if (other.contains(this)) {
 			return other;
 		}
-		let start = Position.Min(other.start, this._start);
-		let end = Position.Max(other.end, this.end);
+		const start = Position.Min(other.start, this._start);
+		const end = Position.Max(other.end, this.end);
 		return new Range(start, end);
 	}
 
@@ -480,7 +480,7 @@ export class TextEdit {
 	}
 
 	static setEndOfLine(eol: EndOfLine): TextEdit {
-		let ret = new TextEdit(new Range(new Position(0, 0), new Position(0, 0)), '');
+		const ret = new TextEdit(new Range(new Position(0, 0), new Position(0, 0)), '');
 		ret.newEol = eol;
 		return ret;
 	}
@@ -616,7 +616,7 @@ export class WorkspaceEdit implements vscode.WorkspaceEdit {
 	}
 
 	get(uri: URI): TextEdit[] {
-		let res: TextEdit[] = [];
+		const res: TextEdit[] = [];
 		for (let candidate of this._edits) {
 			if (candidate._type === 2 && candidate.uri.toString() === uri.toString()) {
 				res.push(candidate.edit);
@@ -626,7 +626,7 @@ export class WorkspaceEdit implements vscode.WorkspaceEdit {
 	}
 
 	entries(): [URI, TextEdit[]][] {
-		let textEdits = new Map<string, [URI, TextEdit[]]>();
+		const textEdits = new Map<string, [URI, TextEdit[]]>();
 		for (let candidate of this._edits) {
 			if (candidate._type === 2) {
 				let textEdit = textEdits.get(candidate.uri.toString());
@@ -641,7 +641,7 @@ export class WorkspaceEdit implements vscode.WorkspaceEdit {
 	}
 
 	_allEntries(): ([URI, TextEdit[]] | [URI?, URI?, IFileOperationOptions?])[] {
-		let res: ([URI, TextEdit[]] | [URI?, URI?, IFileOperationOptions?])[] = [];
+		const res: ([URI, TextEdit[]] | [URI?, URI?, IFileOperationOptions?])[] = [];
 		for (let edit of this._edits) {
 			if (edit._type === 1) {
 				res.push([edit.from, edit.to, edit.options]);
@@ -1846,7 +1846,7 @@ export class Task implements vscode.Task {
 		}
 		this.clear();
 		this._execution = value;
-		let type = this._definition.type;
+		const type = this._definition.type;
 		if (Task.EmptyType === type || Task.ProcessType === type || Task.ShellType === type) {
 			this.computeDefinitionBasedOnExecution();
 		}

src/vs/workbench/api/node/extHostWorkspace.ts

@@ -459,7 +459,7 @@ export class ExtHostWorkspace implements ExtHostWorkspaceShape, IExtHostWorkspac
 			excludePattern: options.exclude ? globPatternToString(options.exclude) : undefined
 		};
 
-		let isCanceled = false;
+		const isCanceled = false;
 
 		this._activeSearchCallbacks[requestId] = p => {
 			if (isCanceled) {