feat: allow for custom response parser with parseResponse

README.md

@@ -110,6 +110,18 @@ const response = await $fetch.raw('/sushi')
 // ...
 ```
 
+## ✔️ Custom JSON parsing
+
+By using `parse` option, `$fetch` determines how to parse data.
+
+```js
+// Disable JSON parsing
+await $fetch('/movie?lang=en', { parse: false })
+
+// Use JSON.parse to parse
+await $fetch('/movie?lang=en', { parse: JSON.parse })
+```
+
 ## 📦 Bundler Notes
 
 - All targets are exported with Module and CommonJS format and named exports

src/fetch.ts

@@ -3,6 +3,9 @@ import { joinURL, withQuery } from 'ufo'
 import type { Fetch, RequestInfo, RequestInit, Response } from './types'
 import { createFetchError } from './error'
 
+type Parser = (text: string) => any
+type GetParser = (parse: Parser | boolean | undefined) => Parser | undefined
+
 export interface CreateFetchOptions { fetch: Fetch }
 
 export type FetchRequest = RequestInfo
@@ -15,6 +18,7 @@ export interface FetchOptions extends Omit<RequestInit, 'body'> {
   baseURL?: string
   body?: RequestInit['body'] | Record<string, any>
   params?: SearchParams
+  parse?: Parser | boolean
   response?: boolean
 }
 
@@ -25,6 +29,14 @@ export interface $Fetch {
   raw<T = any>(request: FetchRequest, opts?: FetchOptions): Promise<FetchResponse<T>>
 }
 
+const getParser: GetParser = (parse) => {
+  if (!parse) {
+    return undefined
+  }
+
+  return parse === true ? destr : parse
+}
+
 export function setHeader (options: FetchOptions, _key: string, value: string) {
   const key = _key.toLowerCase()
   options.headers = options.headers || {}
@@ -59,15 +71,16 @@ export function createFetch ({ fetch }: CreateFetchOptions): $Fetch {
     }
     const response: FetchResponse<any> = await fetch(request, opts as RequestInit)
     const text = await response.text()
-    response.data = destr(text)
+    const parse = getParser(opts?.parse)
+    response.data = parse ? parse(text) : text
     if (!response.ok) {
       throw createFetchError(request, response)
     }
     return response
   }
 
   const $fetch = function (request, opts) {
-    return raw(request, opts).then(r => r.data)
+    return raw(request, { parse: destr, ...opts }).then(r => r.data)
   } as $Fetch
 
   $fetch.raw = raw

test/index.test.ts

@@ -8,7 +8,7 @@ describe('ohmyfetch', () => {
   let listener: Listener
   const getURL = (url: string) => joinURL(listener.url, url)
 
-  it('setup', async () => {
+  beforeEach(async () => {
     const app = createApp()
       .use('/ok', () => 'ok')
       .use('/params', req => (getQuery(req.url || '')))
@@ -17,14 +17,24 @@ describe('ohmyfetch', () => {
     listener = await listen(app)
   })
 
-  afterAll(async () => {
+  afterEach(async () => {
     await listener.close()
   })
 
   it('ok', async () => {
     expect(await $fetch(getURL('ok'))).toBe('ok')
   })
 
+  it('custom parse', async () => {
+    const parser = jest.fn().mockReturnValue('asdf')
+    await $fetch(getURL('ok'), { parse: parser })
+    expect(parser).toHaveBeenCalledTimes(1)
+  })
+
+  it('custom parse false', async () => {
+    expect(await $fetch(getURL('ok'), { parse: false })).toBe('ok')
+  })
+
   it('baseURL', async () => {
     expect(await $fetch('/x?foo=123', { baseURL: getURL('url') })).toBe('/x?foo=123')
   })