feat: implement BodyReadable.bytes (#3391)

(cherry picked from commit db8e642)

README.md

@@ -84,6 +84,7 @@ The `body` mixins are the most common way to format the request/response body. M
 
 - [`.arrayBuffer()`](https://fetch.spec.whatwg.org/#dom-body-arraybuffer)
 - [`.blob()`](https://fetch.spec.whatwg.org/#dom-body-blob)
+- [`.bytes()`](https://fetch.spec.whatwg.org/#dom-body-bytes)
 - [`.json()`](https://fetch.spec.whatwg.org/#dom-body-json)
 - [`.text()`](https://fetch.spec.whatwg.org/#dom-body-text)
 

docs/docs/api/Dispatcher.md

@@ -488,11 +488,13 @@ The `RequestOptions.method` property should not be value `'CONNECT'`.
 
 `body` contains the following additional [body mixin](https://fetch.spec.whatwg.org/#body-mixin) methods and properties:
 
-- `text()`
-- `json()`
-- `arrayBuffer()`
-- `body`
-- `bodyUsed`
+* [`.arrayBuffer()`](https://fetch.spec.whatwg.org/#dom-body-arraybuffer)
+* [`.blob()`](https://fetch.spec.whatwg.org/#dom-body-blob)
+* [`.bytes()`](https://fetch.spec.whatwg.org/#dom-body-bytes)
+* [`.json()`](https://fetch.spec.whatwg.org/#dom-body-json)
+* [`.text()`](https://fetch.spec.whatwg.org/#dom-body-text)
+* `body`
+* `bodyUsed`
 
 `body` can not be consumed twice. For example, calling `text()` after `json()` throws `TypeError`.
 

docs/docs/api/Fetch.md

@@ -28,6 +28,7 @@ This API is implemented as per the standard, you can find documentation on [MDN]
 
 - [`.arrayBuffer()`](https://fetch.spec.whatwg.org/#dom-body-arraybuffer)
 - [`.blob()`](https://fetch.spec.whatwg.org/#dom-body-blob)
+- [`.bytes()`](https://fetch.spec.whatwg.org/#dom-body-bytes)
 - [`.formData()`](https://fetch.spec.whatwg.org/#dom-body-formdata)
 - [`.json()`](https://fetch.spec.whatwg.org/#dom-body-json)
 - [`.text()`](https://fetch.spec.whatwg.org/#dom-body-text)

lib/api/readable.js

@@ -121,6 +121,11 @@ class BodyReadable extends Readable {
     return consume(this, 'blob')
   }
 
+  // https://fetch.spec.whatwg.org/#dom-body-bytes
+  async bytes () {
+    return consume(this, 'bytes')
+  }
+
   // https://fetch.spec.whatwg.org/#dom-body-arraybuffer
   async arrayBuffer () {
     return consume(this, 'arrayBuffer')
@@ -306,6 +311,31 @@ function chunksDecode (chunks, length) {
   return buffer.utf8Slice(start, bufferLength)
 }
 
+/**
+ * @param {Buffer[]} chunks
+ * @param {number} length
+ * @returns {Uint8Array}
+ */
+function chunksConcat (chunks, length) {
+  if (chunks.length === 0 || length === 0) {
+    return new Uint8Array(0)
+  }
+  if (chunks.length === 1) {
+    // fast-path
+    return new Uint8Array(chunks[0])
+  }
+  const buffer = new Uint8Array(Buffer.allocUnsafeSlow(length).buffer)
+
+  let offset = 0
+  for (let i = 0; i < chunks.length; ++i) {
+    const chunk = chunks[i]
+    buffer.set(chunk, offset)
+    offset += chunk.length
+  }
+
+  return buffer
+}
+
 function consumeEnd (consume) {
   const { type, body, resolve, stream, length } = consume
 
@@ -315,17 +345,11 @@ function consumeEnd (consume) {
     } else if (type === 'json') {
       resolve(JSON.parse(chunksDecode(body, length)))
     } else if (type === 'arrayBuffer') {
-      const dst = new Uint8Array(length)
-
-      let pos = 0
-      for (const buf of body) {
-        dst.set(buf, pos)
-        pos += buf.byteLength
-      }
-
-      resolve(dst.buffer)
+      resolve(chunksConcat(body, length).buffer)
     } else if (type === 'blob') {
       resolve(new Blob(body, { type: stream[kContentType] }))
+    } else if (type === 'bytes') {
+      resolve(chunksConcat(body, length))
     }
 
     consumeFinish(consume)

test/client-request.js

@@ -655,6 +655,32 @@ test('request arrayBuffer', async (t) => {
   await t.completed
 })
 
+test('request bytes', async (t) => {
+  t = tspl(t, { plan: 2 })
+
+  const obj = { asd: true }
+  const server = createServer((req, res) => {
+    res.end(JSON.stringify(obj))
+  })
+  after(() => server.close())
+
+  server.listen(0, async () => {
+    const client = new Client(`http://localhost:${server.address().port}`)
+    after(() => client.destroy())
+
+    const { body } = await client.request({
+      path: '/',
+      method: 'GET'
+    })
+    const bytes = await body.bytes()
+
+    t.deepStrictEqual(new TextEncoder().encode(JSON.stringify(obj)), bytes)
+    t.ok(bytes instanceof Uint8Array)
+  })
+
+  await t.completed
+})
+
 test('request body', async (t) => {
   t = tspl(t, { plan: 1 })
 

test/readable.js

@@ -83,6 +83,27 @@ describe('Readable', () => {
     t.deepStrictEqual(arrayBuffer, expected)
   })
 
+  test('.bytes()', async function (t) {
+    t = tspl(t, { plan: 1 })
+
+    function resume () {
+    }
+    function abort () {
+    }
+    const r = new Readable({ resume, abort })
+
+    r.push(Buffer.from('hello'))
+    r.push(Buffer.from(' world'))
+
+    process.nextTick(() => {
+      r.push(null)
+    })
+
+    const bytes = await r.bytes()
+
+    t.deepStrictEqual(bytes, new TextEncoder().encode('hello world'))
+  })
+
   test('.json()', async function (t) {
     t = tspl(t, { plan: 1 })
 

test/types/readable.test-d.ts

@@ -20,6 +20,9 @@ expectAssignable<BodyReadable>(new BodyReadable())
   // blob
   expectAssignable<Promise<Blob>>(readable.blob())
 
+  // bytes
+  expectAssignable<Promise<Uint8Array>>(readable.bytes())
+
   // arrayBuffer
   expectAssignable<Promise<ArrayBuffer>>(readable.arrayBuffer())
 

types/dispatcher.d.ts

@@ -244,6 +244,7 @@ declare namespace Dispatcher {
     readonly bodyUsed: boolean;
     arrayBuffer(): Promise<ArrayBuffer>;
     blob(): Promise<Blob>;
+    bytes(): Promise<Uint8Array>;
     formData(): Promise<never>;
     json(): Promise<unknown>;
     text(): Promise<string>;

types/readable.d.ts

@@ -25,6 +25,11 @@ declare class BodyReadable extends Readable {
    */
   blob(): Promise<Blob>
 
+  /** Consumes and returns the body as an Uint8Array
+   *  https://fetch.spec.whatwg.org/#dom-body-bytes
+   */
+  bytes(): Promise<Uint8Array>
+
   /** Consumes and returns the body as an ArrayBuffer
    *  https://fetch.spec.whatwg.org/#dom-body-arraybuffer
    */