feat(types): can specify the ResponseBody type of cy.request (#16743)

cli/types/cypress.d.ts

@@ -1470,7 +1470,7 @@ declare namespace Cypress {
      * @example
      *    cy.request('http://dev.local/seed')
      */
-    request(url: string, body?: RequestBody): Chainable<Response>
+    request<T = any>(url: string, body?: RequestBody): Chainable<Response<T>>
     /**
      * Make an HTTP request with specific method.
      *
@@ -1478,7 +1478,7 @@ declare namespace Cypress {
      * @example
      *    cy.request('POST', 'http://localhost:8888/users', {name: 'Jane'})
      */
-    request(method: HttpMethod, url: string, body?: RequestBody): Chainable<Response>
+    request<T = any>(method: HttpMethod, url: string, body?: RequestBody): Chainable<Response<T>>
     /**
      * Make an HTTP request with specific behavior.
      *
@@ -1489,7 +1489,7 @@ declare namespace Cypress {
      *      followRedirect: false // turn off following redirects
      *    })
      */
-    request(options: Partial<RequestOptions>): Chainable<Response>
+    request<T = any>(options: Partial<RequestOptions>): Chainable<Response<T>>
 
     /**
      * Get the root DOM element.
@@ -5502,9 +5502,9 @@ declare namespace Cypress {
     consoleProps(): ObjectLike
   }
 
-  interface Response {
+  interface Response<T> {
     allRequestResponses: any[]
-    body: any
+    body: T
     duration: number
     headers: { [key: string]: string | string[] }
     isOkStatusCode: boolean

cli/types/tests/kitchen-sink.ts

@@ -85,7 +85,7 @@ cy.request({
   method: "POST",
   body: {}
 }).then((resp) => {
-  resp // $ExpectType Response
+  resp // $ExpectType Response<any>
   resp.redirectedToUrl // $ExpectType string | undefined
   resp.redirects // $ExpectType string[] | undefined
   resp.headers // $ExpectType { [key: string]: string | string[]; }
@@ -100,6 +100,30 @@ cy.request({
   }
 })
 
+// Users can specify body type.
+// https://github.com/cypress-io/cypress/issues/9109
+interface ResBody {
+  x: number
+  y: string
+}
+
+cy.request<ResBody>('http://goooooogle.com', {})
+.then((resp) => {
+  resp // $ExpectType Response<ResBody>
+})
+
+cy.request<ResBody>('post', 'http://goooooogle.com', {})
+.then((resp) => {
+  resp // $ExpectType Response<ResBody>
+})
+
+cy.request<ResBody>({
+  url: 'http://goooooogle.com',
+  body: {}
+}).then((resp) => {
+  resp // $ExpectType Response<ResBody>
+})
+
 // if you want a separate variable, you need specify its type
 // otherwise TSC does not cast string "POST" as HttpMethod
 // https://github.com/cypress-io/cypress/issues/2093