set exactOptionalPropertyTypes: true, improved types

benchmark/index.ts

@@ -12,6 +12,12 @@ const serverAdapter = createServerAdapter(async req => {
   return Response.json({ message: `Hello, ${name}!` });
 });
 
+// @ts-ignore Type 'ServerAdapter<{}, ServerAdapterBaseObject<{}, (req: Request) => Promise<Response>>>' is not assignable to type 'RequestListener<typeof IncomingMessage, typeof ServerResponse>'.
+// Types of parameters 'req' and 'req' are incompatible.
+// Type 'IncomingMessage' is not assignable to type 'NodeRequest' with 'exactOptionalPropertyTypes: true'. Consider adding 'undefined' to the types of the target's properties.
+//   Types of property 'url' are incompatible.
+//     Type 'string | undefined' is not assignable to type 'string'.
+//       Type 'undefined' is not assignable to type 'string'.
 createServer(serverAdapter).listen(4000, () => {
   console.log('listening on 0.0.0.0:4000');
 });

e2e/shared-scripts/src/types.ts

@@ -3,8 +3,8 @@ import { OutputValue, Stack } from '@pulumi/pulumi/automation';
 
 export type DeploymentConfiguration<TProgramOutput = any> = {
   name: string;
-  prerequisites?: (stack: Stack) => Promise<void>;
-  config?: (stack: Stack) => Promise<void>;
+  prerequisites?: ((stack: Stack) => Promise<void>) | undefined;
+  config?: ((stack: Stack) => Promise<void>) | undefined;
   program: () => Promise<{
     [K in keyof TProgramOutput]: Output<TProgramOutput[K]> | TProgramOutput[K];
   }>;

e2e/vercel/scripts/createVercelDeployment.ts

@@ -104,7 +104,11 @@ class VercelProvider implements pulumi.dynamic.ResourceProvider {
 export class VercelDeployment extends pulumi.dynamic.Resource {
   public readonly url!: pulumi.Output<string>;
 
-  constructor(name: string, props: VercelDeploymentInputs, opts?: pulumi.CustomResourceOptions) {
+  constructor(
+    name: string,
+    props: VercelDeploymentInputs,
+    opts?: pulumi.CustomResourceOptions | undefined,
+  ) {
     super(
       new VercelProvider(),
       name,

packages/cookie-store/src/CookieStore.ts

@@ -8,7 +8,7 @@ import {
 } from './types.js';
 
 export class CookieStore extends EventTarget {
-  onchange?: (event: CookieChangeEvent) => void;
+  onchange?: ((event: CookieChangeEvent) => void) | undefined;
 
   private cookieMap = new Map<string, Cookie>();
 
@@ -22,7 +22,7 @@ export class CookieStore extends EventTarget {
   }
 
   async get(
-    init?: CookieStoreGetOptions['name'] | CookieStoreGetOptions,
+    init?: CookieStoreGetOptions['name'] | CookieStoreGetOptions | undefined,
   ): Promise<Cookie | undefined> {
     if (init == null) {
       throw new TypeError('CookieStoreGetOptions must not be empty');
@@ -32,7 +32,7 @@ export class CookieStore extends EventTarget {
     return (await this.getAll(init))[0];
   }
 
-  async set(init: CookieListItem | string, possibleValue?: string): Promise<void> {
+  async set(init: CookieListItem | string, possibleValue?: string | undefined): Promise<void> {
     const item: CookieListItem = {
       name: '',
       value: '',
@@ -96,7 +96,9 @@ export class CookieStore extends EventTarget {
     }
   }
 
-  async getAll(init?: CookieStoreGetOptions['name'] | CookieStoreGetOptions): Promise<Cookie[]> {
+  async getAll(
+    init?: CookieStoreGetOptions['name'] | CookieStoreGetOptions | undefined,
+  ): Promise<Cookie[]> {
     const cookies = Array.from(this.cookieMap.values());
     if (init == null || Object.keys(init).length === 0) {
       return cookies;

packages/cookie-store/src/parse.ts

@@ -1,7 +1,7 @@
 import { Cookie } from './types.js';
 
 export interface ParseOptions {
-  decode?: boolean;
+  decode?: boolean | undefined;
 }
 
 const decode = decodeURIComponent;

packages/cookie-store/src/types.ts

@@ -1,36 +1,36 @@
 export interface Cookie {
-  domain?: string;
-  expires?: number;
+  domain?: string | undefined;
+  expires?: number | undefined;
   name: string;
-  path?: string;
-  secure?: boolean;
-  sameSite?: CookieSameSite;
+  path?: string | undefined;
+  secure?: boolean | undefined;
+  sameSite?: CookieSameSite | undefined;
   value: string;
-  httpOnly?: boolean;
+  httpOnly?: boolean | undefined;
 }
 
 export interface CookieStoreDeleteOptions {
   name: string;
-  domain?: string;
-  path?: string;
+  domain?: string | undefined;
+  path?: string | undefined;
 }
 
 export interface CookieStoreGetOptions {
-  name?: string;
-  url?: string;
+  name?: string | undefined;
+  url?: string | undefined;
 }
 
 export type CookieSameSite = 'strict' | 'lax' | 'none';
 
 export interface CookieListItem {
-  name?: string;
-  value?: string;
+  name?: string | undefined;
+  value?: string | undefined;
   domain: string | null;
-  path?: string;
+  path?: string | undefined;
   expires: Date | number | null;
-  secure?: boolean;
-  sameSite?: CookieSameSite;
-  httpOnly?: boolean;
+  secure?: boolean | undefined;
+  sameSite?: CookieSameSite | undefined;
+  httpOnly?: boolean | undefined;
 }
 
 export type CookieList = CookieListItem[];

packages/fetch/dist/index.d.ts

@@ -12,7 +12,7 @@ declare module '@whatwg-node/fetch' {
   export const fetch: typeof globalThis.fetch;
   export const Request: typeof globalThis.Request;
   export const Response: typeof globalThis.Response & {
-    json(data: any, init?: ResponseInit): globalThis.Response;
+    json(data: any, init?: ResponseInit | undefined): globalThis.Response;
   };
   export const Headers: typeof globalThis.Headers;
   export const FormData: typeof globalThis.FormData;
@@ -30,24 +30,24 @@ declare module '@whatwg-node/fetch' {
   export const URLPattern: _URLPattern;
   export interface FormDataLimits {
     /* Max field name size (in bytes). Default: 100. */
-    fieldNameSize?: number;
+    fieldNameSize?: number | undefined;
     /* Max field value size (in bytes). Default: 1MB. */
-    fieldSize?: number;
+    fieldSize?: number | undefined;
     /* Max number of fields. Default: Infinity. */
-    fields?: number;
+    fields?: number | undefined;
     /* For multipart forms, the max file size (in bytes). Default: Infinity. */
-    fileSize?: number;
+    fileSize?: number | undefined;
     /* For multipart forms, the max number of file fields. Default: Infinity. */
-    files?: number;
+    files?: number | undefined;
     /* For multipart forms, the max number of parts (fields + files). Default: Infinity. */
-    parts?: number;
+    parts?: number | undefined;
     /* For multipart forms, the max number of header key-value pairs to parse. Default: 2000. */
-    headerSize?: number;
+    headerSize?: number | undefined;
   }
   export const createFetch: (opts?: {
-    useNodeFetch?: boolean;
-    formDataLimits?: FormDataLimits;
-  }) => {
+    useNodeFetch?: boolean | undefined;
+    formDataLimits?: FormDataLimits | undefined;
+  } | undefined) => {
     fetch: typeof fetch;
     Request: typeof Request;
     Response: typeof Response;

packages/fetchache/src/index.ts

@@ -170,11 +170,11 @@ export interface KeyValueCacheSetOptions {
    * Specified in **seconds**, the time-to-live (TTL) value limits the lifespan
    * of the data being stored in the cache.
    */
-  ttl?: number | null;
+  ttl?: number | null | undefined;
 }
 
 export interface KeyValueCache<V = any> {
   get(key: string): Promise<V | undefined>;
-  set(key: string, value: V, options?: KeyValueCacheSetOptions): Promise<void>;
+  set(key: string, value: V, options?: KeyValueCacheSetOptions | undefined): Promise<void>;
   delete(key: string): Promise<boolean | void>;
 }

packages/node-fetch/src/Blob.ts

@@ -40,7 +40,7 @@ export class PonyfillBlob implements Blob {
   private encoding: BufferEncoding;
   constructor(
     private blobParts: BlobPart[],
-    options?: BlobOptions,
+    options?: BlobOptions | undefined,
   ) {
     this.type = options?.type || 'application/octet-stream';
     this.encoding = options?.encoding || 'utf8';
@@ -131,5 +131,5 @@ export class PonyfillBlob implements Blob {
 
 export interface PonyfillBlob {
   prototype: Blob;
-  new (blobParts?: BlobPart[], options?: BlobPropertyBag): Blob;
+  new (blobParts?: BlobPart[] | undefined, options?: BlobPropertyBag | undefined): Blob;
 }

packages/node-fetch/src/Body.ts

@@ -25,23 +25,23 @@ export type BodyPonyfillInit =
 
 export interface FormDataLimits {
   /* Max field name size (in bytes). Default: 100. */
-  fieldNameSize?: number;
+  fieldNameSize?: number | undefined;
   /* Max field value size (in bytes). Default: 1MB. */
-  fieldSize?: number;
+  fieldSize?: number | undefined;
   /* Max number of fields. Default: Infinity. */
-  fields?: number;
+  fields?: number | undefined;
   /* For multipart forms, the max file size (in bytes). Default: Infinity. */
-  fileSize?: number;
+  fileSize?: number | undefined;
   /* For multipart forms, the max number of file fields. Default: Infinity. */
-  files?: number;
+  files?: number | undefined;
   /* For multipart forms, the max number of parts (fields + files). Default: Infinity. */
-  parts?: number;
+  parts?: number | undefined;
   /* For multipart forms, the max number of header key-value pairs to parse. Default: 2000. */
-  headerSize?: number;
+  headerSize?: number | undefined;
 }
 
 export interface PonyfillBodyOptions {
-  formDataLimits?: FormDataLimits;
+  formDataLimits?: FormDataLimits | undefined;
 }
 
 export class PonyfillBody<TJSON = any> implements Body {
@@ -60,7 +60,7 @@ export class PonyfillBody<TJSON = any> implements Body {
     this.bodyType = bodyType;
   }
 
-  private bodyType?: BodyInitType;
+  private bodyType?: BodyInitType | undefined;
 
   private _bodyFactory: () => PonyfillReadableStream<Uint8Array> | null = () => null;
   private _generatedBody: PonyfillReadableStream<Uint8Array> | null = null;
@@ -169,7 +169,7 @@ export class PonyfillBody<TJSON = any> implements Body {
     });
   }
 
-  formData(opts?: { formDataLimits: FormDataLimits }): Promise<PonyfillFormData> {
+  formData(opts?: { formDataLimits: FormDataLimits } | undefined): Promise<PonyfillFormData> {
     if (this.bodyType === BodyInitType.FormData) {
       return Promise.resolve(this.bodyInit as PonyfillFormData);
     }
@@ -280,7 +280,7 @@ export class PonyfillBody<TJSON = any> implements Body {
 }
 
 function processBodyInit(bodyInit: BodyPonyfillInit | null): {
-  bodyType?: BodyInitType;
+  bodyType?: BodyInitType | undefined;
   contentType: string | null;
   contentLength: number | null;
   bodyFactory(): PonyfillReadableStream<Uint8Array> | null;

packages/node-fetch/src/File.ts

@@ -5,7 +5,7 @@ export class PonyfillFile extends PonyfillBlob implements File {
   constructor(
     fileBits: BlobPart[],
     public name: string,
-    options?: FilePropertyBag,
+    options?: FilePropertyBag | undefined,
   ) {
     super(fileBits, options);
     this.lastModified = options?.lastModified || Date.now();

packages/node-fetch/src/FormData.ts

@@ -6,8 +6,8 @@ export class PonyfillFormData implements FormData {
   private map = new Map<string, FormDataEntryValue[]>();
 
   append(name: string, value: string): void;
-  append(name: string, value: PonyfillBlob, fileName?: string): void;
-  append(name: string, value: PonyfillBlob | string, fileName?: string): void {
+  append(name: string, value: PonyfillBlob, fileName?: string | undefined): void;
+  append(name: string, value: PonyfillBlob | string, fileName?: string | undefined): void {
     let values = this.map.get(name);
     if (!values) {
       values = [];
@@ -37,8 +37,8 @@ export class PonyfillFormData implements FormData {
   }
 
   set(name: string, value: string): void;
-  set(name: string, value: PonyfillBlob, fileName?: string): void;
-  set(name: string, value: PonyfillBlob | string, fileName?: string): void {
+  set(name: string, value: PonyfillBlob, fileName?: string | undefined): void;
+  set(name: string, value: PonyfillBlob | string, fileName?: string | undefined): void {
     const entry: FormDataEntryValue = isBlob(value)
       ? getNormalizedFile(name, value, fileName)
       : value;
@@ -133,7 +133,7 @@ export function getStreamFromFormData(
   });
 }
 
-function getNormalizedFile(name: string, blob: PonyfillBlob, fileName?: string) {
+function getNormalizedFile(name: string, blob: PonyfillBlob, fileName?: string | undefined) {
   if (blob instanceof PonyfillFile) {
     if (fileName != null) {
       return new PonyfillFile([blob], fileName, {

packages/node-fetch/src/Headers.ts

@@ -11,7 +11,7 @@ export class PonyfillHeaders implements Headers {
   private objectNormalizedKeysOfHeadersInit: string[] = [];
   private objectOriginalKeysOfHeadersInit: string[] = [];
 
-  constructor(private headersInit?: PonyfillHeadersInit) {}
+  constructor(private headersInit?: PonyfillHeadersInit | undefined) {}
 
   // perf: we don't need to build `this.map` for Requests, as we can access the headers directly
   private _get(key: string) {

packages/node-fetch/src/ReadableStream.ts

@@ -129,7 +129,7 @@ export class PonyfillReadableStream<T> implements ReadableStream<T> {
 
   getReader(options: { mode: 'byob' }): ReadableStreamBYOBReader;
   getReader(): ReadableStreamDefaultReader<T>;
-  getReader(_options?: ReadableStreamGetReaderOptions): ReadableStreamReader<T> {
+  getReader(_options?: ReadableStreamGetReaderOptions | undefined): ReadableStreamReader<T> {
     const iterator = this.readable[Symbol.asyncIterator]();
     this.locked = true;
     return {

packages/node-fetch/src/Request.ts

@@ -8,19 +8,19 @@ function isRequest(input: any): input is PonyfillRequest {
 
 export type RequestPonyfillInit = PonyfillBodyOptions &
   Omit<RequestInit, 'body' | 'headers'> & {
-    body?: BodyPonyfillInit | null;
-    headers?: PonyfillHeadersInit;
-    headersSerializer?: HeadersSerializer;
-    agent?: Agent;
+    body?: BodyPonyfillInit | null | undefined;
+    headers?: PonyfillHeadersInit | undefined;
+    headersSerializer?: HeadersSerializer | undefined;
+    agent?: Agent | undefined;
   };
 
 type HeadersSerializer = (
   headers: Headers,
-  onContentLength?: (contentLength: string) => void,
+  onContentLength?: ((contentLength: string) => void) | undefined,
 ) => string[];
 
 export class PonyfillRequest<TJSON = any> extends PonyfillBody<TJSON> implements Request {
-  constructor(input: RequestInfo | URL, options?: RequestPonyfillInit) {
+  constructor(input: RequestInfo | URL, options?: RequestPonyfillInit | undefined) {
     let url: string | undefined;
     let bodyInit: BodyPonyfillInit | null = null;
     let requestInit: RequestPonyfillInit | undefined;
@@ -85,7 +85,7 @@ export class PonyfillRequest<TJSON = any> extends PonyfillBody<TJSON> implements
     }
   }
 
-  headersSerializer?: HeadersSerializer;
+  headersSerializer?: HeadersSerializer | undefined;
   cache: RequestCache;
   credentials: RequestCredentials;
   destination: RequestDestination;
@@ -99,7 +99,7 @@ export class PonyfillRequest<TJSON = any> extends PonyfillBody<TJSON> implements
   referrer: string;
   referrerPolicy: ReferrerPolicy;
   url: string;
-  agent?: Agent;
+  agent?: Agent | undefined;
 
   private _signal: AbortSignal | undefined | null;
 

packages/node-fetch/src/Response.ts

@@ -4,18 +4,18 @@ import { isHeadersLike, PonyfillHeaders, PonyfillHeadersInit } from './Headers.j
 
 export type ResponsePonyfilInit = PonyfillBodyOptions &
   Omit<ResponseInit, 'headers'> & {
-    url?: string;
-    redirected?: boolean;
-    headers?: PonyfillHeadersInit;
-    type?: ResponseType;
+    url?: string | undefined;
+    redirected?: boolean | undefined;
+    headers?: PonyfillHeadersInit | undefined;
+    type?: ResponseType | undefined;
   };
 
 const JSON_CONTENT_TYPE = 'application/json; charset=utf-8';
 
 export class PonyfillResponse<TJSON = any> extends PonyfillBody<TJSON> implements Response {
   headers: Headers;
 
-  constructor(body?: BodyPonyfillInit | null, init?: ResponsePonyfilInit) {
+  constructor(body?: BodyPonyfillInit | null | undefined, init?: ResponsePonyfilInit | undefined) {
     super(body || null, init);
     this.headers =
       init?.headers && isHeadersLike(init.headers)