fetch: improve output for FormData, Response, Request

lib/web/fetch/formdata.js

@@ -6,6 +6,7 @@ const { kEnumerableProperty } = require('../../core/util')
 const { File: UndiciFile, FileLike, isFileLike } = require('./file')
 const { webidl } = require('./webidl')
 const { File: NativeFile } = require('node:buffer')
+const nodeUtil = require('node:util')
 
 /** @type {globalThis['File']} */
 const File = NativeFile ?? UndiciFile
@@ -154,6 +155,15 @@ class FormData {
       this[kState].push(entry)
     }
   }
+
+  [nodeUtil.inspect.custom] (depth, options) {
+    let output = 'FormData:\n'
+    this[kState].forEach(entry => {
+      output += `${entry.name}: ${entry.value}\n`
+    })
+
+    return output
+  }
 }
 
 iteratorMixin('FormData', FormData, kState, 'name', 'value')

lib/web/fetch/request.js

@@ -6,6 +6,7 @@ const { extractBody, mixinBody, cloneBody } = require('./body')
 const { Headers, fill: fillHeaders, HeadersList } = require('./headers')
 const { FinalizationRegistry } = require('./dispatcher-weakref')()
 const util = require('../../core/util')
+const nodeUtil = require('node:util')
 const {
   isValidHTTPToken,
   sameOrigin,
@@ -771,6 +772,39 @@ class Request {
     // 4. Return clonedRequestObject.
     return fromInnerRequest(clonedRequest, ac.signal, this[kHeaders][kGuard], this[kRealm])
   }
+
+  [nodeUtil.inspect.custom] (depth, options) {
+    if (options.depth === null) {
+      options.depth = 2
+    }
+
+    const properties = {
+      method: this.method,
+      url: this.url,
+      headers: this.headers,
+      destination: this.destination,
+      referrer: this.referrer,
+      referrerPolicy: this.referrerPolicy,
+      mode: this.mode,
+      credentials: this.credentials,
+      cache: this.cache,
+      redirect: this.redirect,
+      integrity: this.integrity,
+      keepalive: this.keepalive,
+      isReloadNavigation: this.isReloadNavigation,
+      isHistoryNavigation: this.isHistoryNavigation,
+      signal: this.signal,
+      body: this.body,
+      bodyUsed: this.bodyUsed,
+      ok: this.ok,
+      redirected: this.redirected,
+      status: this.status,
+      statusText: this.statusText,
+      type: this.type
+    }
+
+    return nodeUtil.formatWithOptions(options, { ...properties })
+  }
 }
 
 mixinBody(Request)

lib/web/fetch/response.js

@@ -3,6 +3,7 @@
 const { Headers, HeadersList, fill } = require('./headers')
 const { extractBody, cloneBody, mixinBody } = require('./body')
 const util = require('../../core/util')
+const nodeUtil = require('node:util')
 const { kEnumerableProperty } = util
 const {
   isValidReasonPhrase,
@@ -252,6 +253,21 @@ class Response {
     // clonedResponse, this’s headers’s guard, and this’s relevant Realm.
     return fromInnerResponse(clonedResponse, this[kHeaders][kGuard], this[kRealm])
   }
+
+  [nodeUtil.inspect.custom] (depth, options) {
+    if (options.depth === null) {
+      options.depth = 2
+    }
+
+    const { status, statusText, headersList } = this[kState]
+    const properties = {
+      status,
+      statusText,
+      headers: headersList
+    }
+
+    return nodeUtil.formatWithOptions(options, `Response ${nodeUtil.inspect(properties)}`)
+  }
 }
 
 mixinBody(Response)

test/fetch/formdata-inspect-custom.js

@@ -0,0 +1,16 @@
+'use strict'
+
+const { FormData } = require('../../')
+const { inspect } = require('node:util')
+const { test } = require('node:test')
+const assert = require('node:assert')
+
+test('FormData class custom inspection', () => {
+  const formData = new FormData()
+  formData.append('username', 'john_doe')
+  formData.append('email', 'john@example.com')
+
+  const expectedOutput = 'FormData:\nusername: john_doe\nemail: john@example.com\n'
+
+  assert.deepStrictEqual(inspect(formData), expectedOutput)
+})

test/fetch/request-inspect-custom.js

@@ -0,0 +1,46 @@
+'use strict'
+
+const { describe, it } = require('node:test')
+const assert = require('assert')
+const util = require('util')
+const { Request } = require('../../')
+
+describe('Request custom inspection', () => {
+  it('should return a custom inspect output', () => {
+    const request = new Request('https://example.com/api', {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json'
+      }
+    })
+
+    const inspectedOutput = util.inspect(request)
+
+    const expectedOutput = `{
+  method: 'POST',
+  url: 'https://example.com/api',
+  headers: Headers { 'Content-Type': 'application/json' },
+  destination: '',
+  referrer: 'about:client',
+  referrerPolicy: '',
+  mode: 'cors',
+  credentials: 'same-origin',
+  cache: 'default',
+  redirect: 'follow',
+  integrity: '',
+  keepalive: false,
+  isReloadNavigation: false,
+  isHistoryNavigation: false,
+  signal: AbortSignal { aborted: false },
+  body: null,
+  bodyUsed: false,
+  ok: undefined,
+  redirected: undefined,
+  status: undefined,
+  statusText: undefined,
+  type: undefined
+}`
+
+    assert.strictEqual(inspectedOutput, expectedOutput)
+  })
+})

test/fetch/response-inspect-custom.js

@@ -0,0 +1,23 @@
+'use strict'
+
+const { describe, it } = require('node:test')
+const assert = require('assert')
+const util = require('util')
+const { Response } = require('../../')
+
+describe('Response custom inspection', () => {
+  it('should return a custom inspect output', () => {
+    const response = new Response(null)
+    const inspectedOutput = util.inspect(response)
+    const expectedOutput = `Response {
+  status: 200,
+  statusText: '',
+  headers: HeadersList {
+    cookies: null,
+    [Symbol(headers map)]: Map(0) {},
+    [Symbol(headers map sorted)]: null
+  }
+}`
+    assert.strictEqual(inspectedOutput, expectedOutput)
+  })
+})