Add Fetch API types as accepted mock parameters (#291)

* Add Fetch API types as accepted mock parameters

* Ran the formatter

---------

Co-authored-by: Eugene Fidelin <eugene.fidelin@gmail.com>

README.md

@@ -105,8 +105,8 @@ it('should handle expressjs requests', () => {
 ```
 
 The expected type parameter in the mock request and response expects any type that extends the NodeJS
-`http.IncomingRequest` interface. This means you can also mock requests coming from other frameworks
-too. An example for NextJS request will look like this:
+`http.IncomingRequest` interface or Fetch API `Request` class. This means you can also mock requests
+coming from other frameworks too. An example for NextJS request will look like this:
 
 ```ts
 it('should handle nextjs requests', () => {
@@ -123,6 +123,23 @@ it('should handle nextjs requests', () => {
 });
 ```
 
+It is also possible to mock requests from the NextJS new AppRouter:
+
+```ts
+it('should handle nextjs app reouter requests', () => {
+    const mockExpressRequest = httpMocks.createRequest<NextRequest>({
+        method: 'GET',
+        url: '/user/42',
+        params: {
+            id: 42
+        }
+    });
+    const mockExpressResponse = httpMocks.createResponse<NextResponse>();
+
+    // ... the rest of the test as above.
+});
+```
+
 ## API
 
 ### .createRequest()

lib/http-mock.d.ts

@@ -1,6 +1,9 @@
 import { Request, Response, CookieOptions } from 'express';
 import { IncomingMessage, OutgoingMessage } from 'http';
 
+export type RequestType = IncomingMessage | globalThis.Request;
+export type ResponseType = OutgoingMessage | globalThis.Response;
+
 export type RequestMethod = 'CONNECT' | 'DELETE' | 'GET' | 'HEAD' | 'OPTIONS' | 'PATCH' | 'POST' | 'PUT' | 'TRACE';
 
 export interface Params {
@@ -105,7 +108,7 @@ export interface RequestOptions {
     [key: string]: any;
 }
 
-export type MockRequest<T extends IncomingMessage> = T & {
+export type MockRequest<T extends RequestType> = T & {
     _setParameter: (key: string, value?: string) => void;
     _setSessionVariable: (variable: string, value?: string) => void;
     _setCookiesVariable: (variable: string, value?: string) => void;
@@ -134,7 +137,7 @@ export type ResponseCookie = {
     options: CookieOptions;
 };
 
-export type MockResponse<T extends OutgoingMessage> = T & {
+export type MockResponse<T extends ResponseType> = T & {
     _isEndCalled: () => boolean;
     _getHeaders: () => Headers;
     _getData: () => any;
@@ -153,16 +156,16 @@ export type MockResponse<T extends OutgoingMessage> = T & {
     cookies: { [name: string]: ResponseCookie };
 };
 
-export function createRequest<T extends IncomingMessage = Request>(options?: RequestOptions): MockRequest<T>;
+export function createRequest<T extends RequestType = Request>(options?: RequestOptions): MockRequest<T>;
 
-export function createResponse<T extends OutgoingMessage = Response>(options?: ResponseOptions): MockResponse<T>;
+export function createResponse<T extends ResponseType = Response>(options?: ResponseOptions): MockResponse<T>;
 
-export interface Mocks<T1 extends IncomingMessage, T2 extends OutgoingMessage> {
+export interface Mocks<T1 extends RequestType, T2 extends ResponseType> {
     req: MockRequest<T1>;
     res: MockResponse<T2>;
 }
 
-export function createMocks<T1 extends IncomingMessage = Request, T2 extends OutgoingMessage = Response>(
+export function createMocks<T1 extends RequestType = Request, T2 extends ResponseType = Response>(
     reqOptions?: RequestOptions,
     resOptions?: ResponseOptions
 ): Mocks<T1, T2>;

test/lib/http-mock.test-d.ts

@@ -27,3 +27,5 @@ expectAssignable<NodeResponse>(createResponse<NodeResponse>());
 expectNotAssignable<ExpressResponse>(createResponse<NodeResponse>());
 
 expectType<Mocks<ExpressRequest, ExpressResponse>>(createMocks());
+// eslint-disable-next-line no-undef
+expectType<Mocks<globalThis.Request, globalThis.Response>>(createMocks<globalThis.Request, globalThis.Response>());

test/lib/mockRequest.spec.ts

@@ -3,8 +3,8 @@ import * as url from 'url';
 import * as querystring from 'querystring';
 import parseRange from 'range-parser';
 import { EventEmitter } from 'events';
-
 import { IncomingMessage } from 'http';
+
 import * as mockRequest from '../../lib/http-mock';
 
 describe('mockRequest', () => {
@@ -281,6 +281,11 @@ describe('mockRequest', () => {
                 expect(request.ips).to.deep.equal([options.ip]);
             });
         });
+
+        it('should be able to create a Fetch API Request object', () => {
+            const request = mockRequest.createRequest<Request>();
+            expect(request.bodyUsed).to.be.undefined;
+        });
     });
 
     describe('.get()/.header()', () => {

test/lib/mockResponse.spec.js

@@ -1,14 +1,13 @@
 const chai = require('chai');
-
-const { expect } = chai;
 const sinon = require('sinon');
 const sinonChai = require('sinon-chai');
 
-chai.use(sinonChai);
-
 const mockResponse = require('../../lib/mockResponse');
 const mockRequest = require('../../lib/mockRequest');
 
+const { expect } = chai;
+chai.use(sinonChai);
+
 describe('mockResponse', () => {
     it('should expose .createResponse()', () => {
         expect(mockResponse.createResponse).to.be.a('function');