Support ArrayBuffer as body (#408)

package.json

@@ -54,6 +54,7 @@
     "resumer": "0.0.0",
     "rollup": "^0.55.1",
     "rollup-plugin-babel": "^3.0.3",
+    "string-to-arraybuffer": "^1.0.0",
     "url-search-params": "^0.10.0",
     "whatwg-url": "^5.0.0"
   },

src/body.js

@@ -40,6 +40,8 @@ export default function Body(body, {
 		// body is blob
 	} else if (Buffer.isBuffer(body)) {
 		// body is buffer
+	} else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is array buffer
 	} else if (body instanceof Stream) {
 		// body is stream
 	} else {
@@ -202,6 +204,11 @@ function consumeBody() {
 		return Body.Promise.resolve(this.body);
 	}
 
+	// body is buffer
+	if (Object.prototype.toString.call(this.body) === '[object ArrayBuffer]') {
+		return Body.Promise.resolve(this.body);
+	}
+
 	// istanbul ignore if: should never happen
 	if (!(this.body instanceof Stream)) {
 		return Body.Promise.resolve(Buffer.alloc(0));
@@ -403,6 +410,9 @@ export function extractContentType(instance) {
 	} else if (Buffer.isBuffer(body)) {
 		// body is buffer
 		return null;
+	} else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is array buffer
+		return null;
 	} else if (typeof body.getBoundary === 'function') {
 		// detect form data input from form-data module
 		return `multipart/form-data;boundary=${body.getBoundary()}`;
@@ -441,6 +451,9 @@ export function getTotalBytes(instance) {
 	} else if (Buffer.isBuffer(body)) {
 		// body is buffer
 		return body.length;
+	} else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is array buffer
+		return body.byteLength;
 	} else if (body && typeof body.getLengthSync === 'function') {
 		// detect form data input from form-data module
 		if (body._lengthRetrievers && body._lengthRetrievers.length == 0 || // 1.x
@@ -483,6 +496,10 @@ export function writeToStream(dest, instance) {
 		// body is buffer
 		dest.write(body);
 		dest.end()
+	} else if (Object.prototype.toString.call(body) === '[object ArrayBuffer]') {
+		// body is array buffer
+		dest.write(Buffer.from(body));
+		dest.end()
 	} else {
 		// body is stream
 		body.pipe(dest);

test/test.js

@@ -7,6 +7,7 @@ import chaiString from 'chai-string';
 import then from 'promise';
 import resumer from 'resumer';
 import FormData from 'form-data';
+import stringToArrayBuffer from 'string-to-arraybuffer';
 import URLSearchParams_Polyfill from 'url-search-params';
 import { URL } from 'whatwg-url';
 
@@ -771,6 +772,21 @@ describe('node-fetch', () => {
 		});
 	});
 
+	it('should allow POST request with ArrayBuffer body', function() {
+		url = `${base}inspect`;
+		opts = {
+			method: 'POST'
+			, body: stringToArrayBuffer('Hello, world!\n')
+		};
+		return fetch(url, opts).then(res => res.json()).then(res => {
+			expect(res.method).to.equal('POST');
+			expect(res.body).to.equal('Hello, world!\n');
+			expect(res.headers['transfer-encoding']).to.be.undefined;
+			expect(res.headers['content-type']).to.be.undefined;
+			expect(res.headers['content-length']).to.equal('14');
+		});
+	});
+
 	it('should allow POST request with blob body without type', function() {
 		url = `${base}inspect`;
 		opts = {