Use more optional chaining in TS extension (#152271)

Use optional chaining in TS extension

Also removes `prefer-const` since this is now enabled globally

extensions/typescript-language-features/.eslintrc.json

@@ -1,5 +1,5 @@
 {
 	"rules": {
-		"prefer-const": "error"
+		"@typescript-eslint/prefer-optional-chain": "warn"
 	}
 }

extensions/typescript-language-features/src/languageFeatures/codeLens/baseCodeLensProvider.ts

@@ -88,7 +88,7 @@ export function getSymbolRange(
 	}
 
 	// In older versions, we have to calculate this manually. See #23924
-	const span = item.spans && item.spans[0];
+	const span = item.spans?.[0];
 	if (!span) {
 		return undefined;
 	}

extensions/typescript-language-features/src/languageFeatures/signatureHelp.ts

@@ -64,7 +64,7 @@ class TypeScriptSignatureHelpProvider implements vscode.SignatureHelpProvider {
 
 	private getActiveParameter(info: Proto.SignatureHelpItems): number {
 		const activeSignature = info.items[info.selectedItemIndex];
-		if (activeSignature && activeSignature.isVariadic) {
+		if (activeSignature?.isVariadic) {
 			return Math.min(info.argumentIndex, activeSignature.parameters.length - 1);
 		}
 		return info.argumentIndex;

extensions/typescript-language-features/src/languageFeatures/tagClosing.ts

@@ -53,7 +53,7 @@ class TagClosing extends Disposable {
 			return;
 		}
 
-		const activeDocument = vscode.window.activeTextEditor && vscode.window.activeTextEditor.document;
+		const activeDocument = vscode.window.activeTextEditor?.document;
 		if (document !== activeDocument) {
 			return;
 		}

extensions/typescript-language-features/src/tsServer/versionProvider.electron.ts

@@ -28,7 +28,7 @@ export class DiskTypeScriptVersionProvider implements ITypeScriptVersionProvider
 	public get globalVersion(): TypeScriptVersion | undefined {
 		if (this.configuration?.globalTsdk) {
 			const globals = this.loadVersionsFromSetting(TypeScriptVersionSource.UserSetting, this.configuration.globalTsdk);
-			if (globals && globals.length) {
+			if (globals?.length) {
 				return globals[0];
 			}
 		}
@@ -37,7 +37,7 @@ export class DiskTypeScriptVersionProvider implements ITypeScriptVersionProvider
 
 	public get localVersion(): TypeScriptVersion | undefined {
 		const tsdkVersions = this.localTsdkVersions;
-		if (tsdkVersions && tsdkVersions.length) {
+		if (tsdkVersions?.length) {
 			return tsdkVersions[0];
 		}
 

extensions/typescript-language-features/src/typescriptServiceClient.ts

@@ -883,7 +883,7 @@ export default class TypeScriptServiceClient extends Disposable implements IType
 				this.loadingIndicator.reset();
 
 				const diagnosticEvent = event as Proto.DiagnosticEvent;
-				if (diagnosticEvent.body && diagnosticEvent.body.diagnostics) {
+				if (diagnosticEvent.body?.diagnostics) {
 					this._onDiagnosticsReceived.fire({
 						kind: getDignosticsKind(event),
 						resource: this.toResource(diagnosticEvent.body.file),

extensions/typescript-language-features/src/utils/async.ts

@@ -13,7 +13,7 @@ export class Delayer<T> {
 
 	public defaultDelay: number;
 	private timeout: any; // Timer
-	private completionPromise: Promise<T | null> | null;
+	private completionPromise: Promise<T | undefined> | null;
 	private onSuccess: ((value: T | PromiseLike<T> | undefined) => void) | null;
 	private task: ITask<T> | null;
 
@@ -25,7 +25,7 @@ export class Delayer<T> {
 		this.task = null;
 	}
 
-	public trigger(task: ITask<T>, delay: number = this.defaultDelay): Promise<T | null> {
+	public trigger(task: ITask<T>, delay: number = this.defaultDelay): Promise<T | undefined> {
 		this.task = task;
 		if (delay >= 0) {
 			this.cancelTimeout();
@@ -37,7 +37,7 @@ export class Delayer<T> {
 			}).then(() => {
 				this.completionPromise = null;
 				this.onSuccess = null;
-				const result = this.task && this.task();
+				const result = this.task?.();
 				this.task = null;
 				return result;
 			});

extensions/typescript-language-features/src/utils/codeAction.ts

@@ -12,7 +12,7 @@ export function getEditForCodeAction(
 	client: ITypeScriptServiceClient,
 	action: Proto.CodeAction
 ): vscode.WorkspaceEdit | undefined {
-	return action.changes && action.changes.length
+	return action.changes?.length
 		? typeConverters.WorkspaceEdit.fromFileCodeEdits(client, action.changes)
 		: undefined;
 }
@@ -36,7 +36,7 @@ export async function applyCodeActionCommands(
 	commands: ReadonlyArray<{}> | undefined,
 	token: vscode.CancellationToken,
 ): Promise<boolean> {
-	if (commands && commands.length) {
+	if (commands?.length) {
 		for (const command of commands) {
 			await client.execute('applyCodeActionCommand', { command }, token);
 		}

extensions/typescript-language-features/src/utils/configuration.ts

@@ -15,7 +15,7 @@ export enum TsServerLogLevel {
 
 export namespace TsServerLogLevel {
 	export function fromString(value: string): TsServerLogLevel {
-		switch (value && value.toLowerCase()) {
+		switch (value?.toLowerCase()) {
 			case 'normal':
 				return TsServerLogLevel.Normal;
 			case 'terse':

extensions/typescript-language-features/src/utils/telemetry.ts

@@ -55,7 +55,7 @@ export class VSCodeTelemetryReporter implements TelemetryReporter {
 
 	@memoize
 	private get reporter(): VsCodeTelemetryReporter | null {
-		if (this.packageInfo && this.packageInfo.aiKey) {
+		if (this.packageInfo?.aiKey) {
 			this._reporter = new VsCodeTelemetryReporter(
 				this.packageInfo.name,
 				this.packageInfo.version,