Fix a regression where body was sent after redirect

Fixes #1406

Author: szmarczak

source/core/index.ts

@@ -2071,6 +2071,9 @@ export default class Request extends Duplex implements RequestEvents<Request> {
 				if ('form' in options) {
 					delete options.form;
 				}
+
+				this[kBody] = undefined;
+				delete options.headers['content-length'];
 			}
 
 			if (this.redirects.length >= options.maxRedirects) {

test/redirects.ts

@@ -156,6 +156,21 @@ test('redirects on 303 if GET or HEAD', withServer, async (t, server, got) => {
 	t.is(request.options.method, 'HEAD');
 });
 
+test('removes body on GET redirect', withServer, async (t, server, got) => {
+	server.get('/', (request, response) => request.pipe(response));
+
+	server.post('/seeOther', (_request, response) => {
+		response.writeHead(303, {
+			location: '/'
+		});
+		response.end();
+	});
+
+	const {headers, body} = await got.post('seeOther', {body: 'hello'});
+	t.is(body, '');
+	t.is(headers['content-length'], '0');
+});
+
 test('redirects on 303 response even on post, put, delete', withServer, async (t, server, got) => {
 	server.get('/', reachedHandler);
 

test/stream.ts

@@ -323,6 +323,7 @@ test('piping to got.stream.put()', withServer, async (t, server, got) => {
 });
 
 // See https://github.com/nodejs/node/issues/35237
+// eslint-disable-next-line ava/no-skip-test
 test.skip('no unhandled body stream errors', async t => {
 	const body = new FormData();
 	body.append('upload', fs.createReadStream('/bin/sh'));